java Archives - Ebhor.com

JTable Pagination in Java JDBC and MySQL Database

Here we will see how to develop JTable Pagination in java.

We will use JDBC prepared statement and MySQL Database.

We used NetBeans IDE and Jdk 1.8 to develop this project.

Our Project Structure is as below

To develop this project we used Book Example.

Project Development Steps are

Create table in MySQL Database
SetUp Pagination Project
Create Model (Pojo) Class
Create a DAO class to Perform JDBC Operations
Create Frame to show data in JPanel
Implement Pagination Concepts.

1 Create Table in MySQL Database

We created ebhor database and table called book as below

CREATE TABLE book(
     id        BIGINT(20) UNSIGNED NOT NULL auto_increment,
     name      VARCHAR(200),
     author    VARCHAR(10),
     publication VARCHAR(100),
     add_date   TIMESTAMP DEFAULT CURRENT_TIMESTAMP(),
     PRIMARY KEY (id),
     UNIQUE KEY (name)
  )
engine=innodb
DEFAULT charset=utf8;

CREATE TABLE book(

id BIGINT(20) UNSIGNED NOT NULL auto_increment,

name VARCHAR(200),

author VARCHAR(10),

publication VARCHAR(100),

add_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP(),

PRIMARY KEY (id),

UNIQUE KEY (name)

)

engine=innodb

DEFAULT charset=utf8;

Inserted 100 records on it.

You can use any “MySQL Data Generator like generatedata.com generate 100 rows or as many as you want.

Fig: How to import data in MySQL database

In above figure screen when you scroll down you will find Go button click on it.

Go to browse to see data in table .

After uploading data check you data by clicking on browse in PHPMyAdmin.

Browse the PhpMyAdmin database — Fig: Browse the Book table

Book table created and 100 Records are uploaded in table.

2. SetUp Pagination Project

Create a new Java Project in Netbeans IDE

Select Java in categories and Java Applications in Project.

Provide name “Pagination” to your project

Click on Use Dedicated Folder for Storing Libraries.

How to assign Project Name in NetBeans — Fig: Assign Project Name in NetBeans

Now at left side on project explorer

click on Pagination Project.

there create packages

ebhor.model ebhor.dao ebhor.frame ebhor.pagination

Now right click on library and and click on menu Add Jar/Folder…

Now include mysql-connector-java-5.1.14-bin.jar Jar file

How to add mysql-connector-java-5.1.14-bin.jar in NetBean IDE — Fig: Adding mysql-connector-java-5.1.14-bin.jar in NetBean IDE

Next we will create a Pojo class.

3 Create a Model to hold Data

Inside ebhor.model package create a POJO Class Book

Book class contains field id, name, author publication, addDate field.

All fields getter setter , constructos and toString()

Book.java

package ebhor.model;

import java.io.Serializable;
import java.sql.Timestamp;


public class Book implements Serializable{

    private long id;
    private String name;
    private String author;
    private String publication;
    private Timestamp addDate;
    
    public Book(){
        
    }

    public Book(long id, String name, String author, String publication, Timestamp addDate) {
        this.id = id;
        this.name = name;
        this.author = author;
        this.publication = publication;
        this.addDate = addDate;
    }

    @Override
    public String toString() {
        return "Book{" + "id=" + id + ", name=" + name + ", author=" + author + ", publication=" + publication + ", addDate=" + addDate + '}';
    }

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public String getPublication() {
        return publication;
    }

    public void setPublication(String publication) {
        this.publication = publication;
    }

    public Timestamp getAddDate() {
        return addDate;
    }

    public void setAddDate(Timestamp addDate) {
        this.addDate = addDate;
    }

}

package ebhor.model;

import java.io.Serializable;

import java.sql.Timestamp;

public class Book implements Serializable{

private long id;

private String name;

private String author;

private String publication;

private Timestamp addDate;

public Book(){

}

public Book(long id, String name, String author, String publication, Timestamp addDate) {

this.id = id;

this.name = name;

this.author = author;

this.publication = publication;

this.addDate = addDate;

}

@Override

public String toString() {

return "Book{" + "id=" + id + ", name=" + name + ", author=" + author + ", publication=" + publication + ", addDate=" + addDate + '}';

}

public long getId() {

return id;

}

public void setId(long id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getAuthor() {

return author;

}

public void setAuthor(String author) {

this.author = author;

}

public String getPublication() {

return publication;

}

public void setPublication(String publication) {

this.publication = publication;

}

public Timestamp getAddDate() {

return addDate;

}

public void setAddDate(Timestamp addDate) {

this.addDate = addDate;

}

4 Create a DAO Class to Perform JDBC Operations

Here establish a connection with database.

Extracting data from database are handling .

Inside ebhor.dao following classes are there

ConnectionFactory.java

This class contains a method getConnection() creates connection with MySQL database using database username, password and database name.

getConnection() returns connection Object.

package ebhor.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class ConnectionFactory {

    public static Connection getConnection() {
        Connection c = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            c = DriverManager.getConnection("jdbc:mysql://localhost:3306/ebhor?useUnicode=true&characterEncoding=UTF-8", "ebhor_user", "21V6");
        } catch (ClassNotFoundException e) {
            System.out.println("ClassNotFoundException " + e);
        } catch (SQLException e) {
            System.out.println("SQLException " + e);
        }
        return c;
    }
}

package ebhor.dao;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

public class ConnectionFactory {

public static Connection getConnection() {

Connection c = null;

try {

Class.forName("com.mysql.jdbc.Driver");

c = DriverManager.getConnection("jdbc:mysql://localhost:3306/ebhor?useUnicode=true&characterEncoding=UTF-8", "ebhor_user", "21V6");

} catch (ClassNotFoundException e) {

System.out.println("ClassNotFoundException " + e);

} catch (SQLException e) {

System.out.println("SQLException " + e);

}

return c;

}

BookDAO.java

This class contains two methods

1 fetchBySize() – This method takes two integer arguments

start is used to select start row in book table.
size is used to select specified number of elements from start.

If you pass parameter fetchBySize(11,10) then it will select 10 records from MySQL with starting table row of 11.

Result set values are stored in DefaultTableModel Object.

DefaultTableModel value can easily represent data in JTable.

2. getRowCount() this method is used to find total number of rows in table.

package ebhor.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.swing.table.DefaultTableModel;

public class BookDAO {

    Connection con = null;
    PreparedStatement ps = null;
    ResultSet rs = null;
    int st;//status

    public DefaultTableModel fetchBySize(int start, int size) {
        System.out.println("book frame dao");
        DefaultTableModel model = new DefaultTableModel(new String[]{"Id", "Name", "Author", "Publication",}, 0);
        con = ConnectionFactory.getConnection();
        try {
            String query = "select * from book limit " + start + "," + size;
            System.out.println(query);
            ps = con.prepareStatement(query);
            rs = ps.executeQuery();
            int i = 0;
            while (rs.next()) {
                long id = rs.getLong("id");
                String name = rs.getString("name");
                String author = rs.getString("author");
                String publication = rs.getString("publication");
                model.addRow(new Object[]{id, name, author, publication});
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                con.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        }
        return model;
    }

    public double getRowCount() {
        System.out.println("book table row count");
        con = ConnectionFactory.getConnection();
        long count = 0;
        try {
            String query = "SELECT count(*) FROM book ";
            System.out.println(query);
            ps = con.prepareStatement(query);
            rs = ps.executeQuery();
            while (rs.next()) {
                count = rs.getLong("count(*)");

            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                con.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        }
        return count;
    }
}

package ebhor.dao;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import javax.swing.table.DefaultTableModel;

public class BookDAO {

Connection con = null;

PreparedStatement ps = null;

ResultSet rs = null;

int st;//status

public DefaultTableModel fetchBySize(int start, int size) {

System.out.println("book frame dao");

DefaultTableModel model = new DefaultTableModel(new String[]{"Id", "Name", "Author", "Publication",}, 0);

con = ConnectionFactory.getConnection();

try {

String query = "select * from book limit " + start + "," + size;

System.out.println(query);

ps = con.prepareStatement(query);

rs = ps.executeQuery();

int i = 0;

while (rs.next()) {

long id = rs.getLong("id");

String name = rs.getString("name");

String author = rs.getString("author");

String publication = rs.getString("publication");

model.addRow(new Object[]{id, name, author, publication});

}

} catch (Exception e) {

e.printStackTrace();

} finally {

try {

con.close();

} catch (SQLException ex) {

ex.printStackTrace();

}

return model;

}

public double getRowCount() {

System.out.println("book table row count");

con = ConnectionFactory.getConnection();

long count = 0;

try {

String query = "SELECT count(*) FROM book ";

System.out.println(query);

ps = con.prepareStatement(query);

rs = ps.executeQuery();

while (rs.next()) {

count = rs.getLong("count(*)");

}

} catch (Exception e) {

e.printStackTrace();

} finally {

try {

con.close();

} catch (SQLException ex) {

ex.printStackTrace();

}

return count;

}

5 Create Frame to show data in JPanel

UI designing and Action handling work is done here.

BookFrame.java is created in ebhor.frame package

BookFrame.java contains following methods

1 A Default Constructor –

Here a main JPanel is created with GridLayout.

Two other JPanel is created.

tablePanel -to place JTable and pagingPanel to place Paging buttons.

Inside this getCount() and getPageData() is called.

2 getCount() –

This method work is to find book table record count by calling getRowCount() from BookDAO.java.

It also calculate the total pages for pagination based on PAGE_SIZE field.

3. getPageData() –

Work of this method is to get records from Book Table. and set it to JTable based on page number.

To update pagination details getPaginationDetails() is get called.

4 getPaginationDetails() –

This method is used to get dynamic page numbers from Pagination.java.

According to numbers it generates buttons and add actionListeners to buttons.

Also handle button disable and enable features for first and last page number.

5 ActionPerformed()-

Handle the click actions of dynamically generated buttons.

6 public static void main() –

This function is starting execution point for our program.

package ebhor.frame;

import ebhor.dao.BookDAO;
import java.awt.Color;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.border.TitledBorder;
import javax.swing.table.DefaultTableModel;

public class BookFrame extends JFrame implements ActionListener {

    JTable jTable;
    Container container;
    //  JButton start, end;
    DefaultTableModel model;
    BookDAO dao = new BookDAO();
    /*used for pagination*/
    final int PAGE_SIZE = 10;
    double tableRowCount;
    int totalPages;
    int currentPage;
    int startRow;
    int numbers[];
    JButton[] buttons;
    JPanel mainPanel, tablePanel, pagingPanel;

    BookFrame() {
        System.out.println("calling bookframe");
        container = this.getContentPane();

        mainPanel = new JPanel(new GridLayout(2, 1, 30, 50)); // main panel
        mainPanel.setBorder(BorderFactory.createTitledBorder(BorderFactory.createEtchedBorder(), "Subject Lists", TitledBorder.CENTER, TitledBorder.TOP));

        //create a JTable panel
        tablePanel = new JPanel();
        DefaultTableModel dm = (DefaultTableModel) dao.fetchBySize(0, 10);
        jTable = new JTable(dm);
        tablePanel.add(new JScrollPane(jTable));
        jTable.setRowHeight(23);
        //ading table panel to main panel
        mainPanel.add(tablePanel);

        //paging button panel
        pagingPanel = new JPanel();

        buttons = new JButton[9];
        //adding paging panel to main panel
        mainPanel.add(pagingPanel);
        //adding main panel to container
        container.add(mainPanel);
        getCount();
        getPageData(1);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println("event called" + e.getSource());
        String pageNumber = "";
        if (e.getSource() instanceof JButton) {
            if (((JButton) e.getSource()).getText().equalsIgnoreCase("Start")) {
                pageNumber = "1";
            } else if (((JButton) e.getSource()).getText().equalsIgnoreCase("End")) {
                pageNumber = totalPages + "";
            } else if (((JButton) e.getSource()).getText().equalsIgnoreCase("<<")) {
                pageNumber = (currentPage - 1) + "";
            } else if (((JButton) e.getSource()).getText().equalsIgnoreCase(">>")) {
                pageNumber = (currentPage + 1) + "";
            } else {
                pageNumber = ((JButton) e.getSource()).getText();
            }
            System.out.println("hello " + pageNumber);
            //this.repaint();
            getPageData(Integer.parseInt(pageNumber));
            getPaginationDetails();

        }

    }

    /*get total numbers of record in table*/
    public void getCount() {
        tableRowCount = dao.getRowCount();
        if (tableRowCount > 0) {
            totalPages = (int) Math.ceil(tableRowCount / PAGE_SIZE);
            currentPage = 1;
            System.out.println("row count is " + tableRowCount + "page Count" + totalPages);
        } else {
            JOptionPane.showMessageDialog(null, "No Record to display");
        }

    }

    /*Get data from table based on page no*/
    public void getPageData(int pageNo) {

        currentPage = pageNo;
        //calculate starting row for pagination
        startRow = PAGE_SIZE * (pageNo - 1);
        DefaultTableModel dm = (DefaultTableModel) dao.fetchBySize(startRow, PAGE_SIZE);
        jTable.setModel(dm);
        getPaginationDetails();

    }

    // dynamically generate page numbers 
    public void getPaginationDetails() {
        System.out.println("pagination details");
        int inc = 0;

        System.out.println(currentPage + "  " + totalPages);
        pagingPanel.removeAll();
        pagingPanel.revalidate();
        numbers = ebhor.pagination.Pagination.getPageNos(currentPage, totalPages);

        buttons[0] = new JButton("Start");
        buttons[0].addActionListener(this);
        pagingPanel.add(buttons[0]);
        buttons[1] = new JButton("<<");
        buttons[1].addActionListener(this);
        pagingPanel.add(buttons[1]);

        for (int i = 0; i < numbers.length; i++) {

            if (numbers[i] != 0) {
                buttons[i + 2] = new JButton(numbers[i] + "");
                buttons[i + 2].setBounds(500 + inc, 500, 50, 30);
                buttons[i + 2].addActionListener(this);
                pagingPanel.add(buttons[i + 2]);
                inc += 40;
            }
            if (numbers[i] == currentPage) {
                buttons[i + 2].setBackground(Color.BLUE);
                buttons[i + 2].setForeground(Color.WHITE);

            }
        }
        buttons[7] = new JButton(">>");
        buttons[7].addActionListener(this);
        pagingPanel.add(buttons[7]);
        buttons[8] = new JButton("End");
        buttons[8].addActionListener(this);
        pagingPanel.add(buttons[8]);
        /*if current page is 1 then disable start and previous button*/
        if (currentPage == 1) {
            buttons[0].setEnabled(false);
            buttons[1].setEnabled(false);

        }
        /*if current page is last then disable end and next button*/
        if (currentPage == PAGE_SIZE) {
            buttons[7].setEnabled(false);
            buttons[8].setEnabled(false);

        }
    }

    //start of execution
    public static void main(String[] args) {
        BookFrame frame = new BookFrame();
        frame.setTitle("JTable with Pagination");
        frame.setVisible(true);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    }
}

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package ebhor.frame;

import ebhor.dao.BookDAO;

import java.awt.Color;

import java.awt.Container;

import java.awt.GridLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.BorderFactory;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JOptionPane;

import javax.swing.JPanel;

import javax.swing.JScrollPane;

import javax.swing.JTable;

import javax.swing.border.TitledBorder;

import javax.swing.table.DefaultTableModel;

public class BookFrame extends JFrame implements ActionListener {

JTable jTable;

Container container;

// JButton start, end;

DefaultTableModel model;

BookDAO dao = new BookDAO();

/*used for pagination*/

final int PAGE_SIZE = 10;

double tableRowCount;

int totalPages;

int currentPage;

int startRow;

int numbers[];

JButton[] buttons;

JPanel mainPanel, tablePanel, pagingPanel;

BookFrame() {

System.out.println("calling bookframe");

container = this.getContentPane();

mainPanel = new JPanel(new GridLayout(2, 1, 30, 50)); // main panel

mainPanel.setBorder(BorderFactory.createTitledBorder(BorderFactory.createEtchedBorder(), "Subject Lists", TitledBorder.CENTER, TitledBorder.TOP));

//create a JTable panel

tablePanel = new JPanel();

DefaultTableModel dm = (DefaultTableModel) dao.fetchBySize(0, 10);

jTable = new JTable(dm);

tablePanel.add(new JScrollPane(jTable));

jTable.setRowHeight(23);

//ading table panel to main panel

mainPanel.add(tablePanel);

//paging button panel

pagingPanel = new JPanel();

buttons = new JButton[9];

//adding paging panel to main panel

mainPanel.add(pagingPanel);

//adding main panel to container

container.add(mainPanel);

getCount();

getPageData(1);

}

@Override

public void actionPerformed(ActionEvent e) {

System.out.println("event called" + e.getSource());

String pageNumber = "";

if (e.getSource() instanceof JButton) {

if (((JButton) e.getSource()).getText().equalsIgnoreCase("Start")) {

pageNumber = "1";

} else if (((JButton) e.getSource()).getText().equalsIgnoreCase("End")) {

pageNumber = totalPages + "";

} else if (((JButton) e.getSource()).getText().equalsIgnoreCase("<<")) {

pageNumber = (currentPage - 1) + "";

} else if (((JButton) e.getSource()).getText().equalsIgnoreCase(">>")) {

pageNumber = (currentPage + 1) + "";

} else {

pageNumber = ((JButton) e.getSource()).getText();

}

System.out.println("hello " + pageNumber);

//this.repaint();

getPageData(Integer.parseInt(pageNumber));

getPaginationDetails();

}

/*get total numbers of record in table*/

public void getCount() {

tableRowCount = dao.getRowCount();

if (tableRowCount > 0) {

totalPages = (int) Math.ceil(tableRowCount / PAGE_SIZE);

currentPage = 1;

System.out.println("row count is " + tableRowCount + "page Count" + totalPages);

} else {

JOptionPane.showMessageDialog(null, "No Record to display");

}

/*Get data from table based on page no*/

public void getPageData(int pageNo) {

currentPage = pageNo;

//calculate starting row for pagination

startRow = PAGE_SIZE * (pageNo - 1);

DefaultTableModel dm = (DefaultTableModel) dao.fetchBySize(startRow, PAGE_SIZE);

jTable.setModel(dm);

getPaginationDetails();

}

// dynamically generate page numbers

public void getPaginationDetails() {

System.out.println("pagination details");

int inc = 0;

System.out.println(currentPage + " " + totalPages);

pagingPanel.removeAll();

pagingPanel.revalidate();

numbers = ebhor.pagination.Pagination.getPageNos(currentPage, totalPages);

buttons[0] = new JButton("Start");

buttons[0].addActionListener(this);

pagingPanel.add(buttons[0]);

buttons[1] = new JButton("<<");

buttons[1].addActionListener(this);

pagingPanel.add(buttons[1]);

for (int i = 0; i < numbers.length; i++) {

if (numbers[i] != 0) {

buttons[i + 2] = new JButton(numbers[i] + "");

buttons[i + 2].setBounds(500 + inc, 500, 50, 30);

buttons[i + 2].addActionListener(this);

pagingPanel.add(buttons[i + 2]);

inc += 40;

}

if (numbers[i] == currentPage) {

buttons[i + 2].setBackground(Color.BLUE);

buttons[i + 2].setForeground(Color.WHITE);

}

buttons[7] = new JButton(">>");

buttons[7].addActionListener(this);

pagingPanel.add(buttons[7]);

buttons[8] = new JButton("End");

buttons[8].addActionListener(this);

pagingPanel.add(buttons[8]);

/*if current page is 1 then disable start and previous button*/

if (currentPage == 1) {

buttons[0].setEnabled(false);

buttons[1].setEnabled(false);

}

/*if current page is last then disable end and next button*/

if (currentPage == PAGE_SIZE) {

buttons[7].setEnabled(false);

buttons[8].setEnabled(false);

}

//start of execution

public static void main(String[] args) {

BookFrame frame = new BookFrame();

frame.setTitle("JTable with Pagination");

frame.setVisible(true);

frame.pack();

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

}

6 Implement Pagination Concepts

ebhor.pagination.Pagination class is created to implement pagination concept.

public static int[] getPageNos(int currentPage, int totalPages) is used to implement pagination concept.

it takes two argument currentPage and totalPages to get next set of page numbers and return integer array.

Pagination.java

package ebhor.pagination;

public class Pagination {

    public static int[] getPageNos(int currentPage, int totalPages) {
        int[] pages = new int[5];
        if (currentPage <= 2) {
            System.out.println("currentPage <=2");
            if (totalPages >= 5) {
                System.out.println("if");
                for (int i = 0; i <= 4; i++) {
                    pages[i] = i + 1;
                }
            } else {
                System.out.println("else");
                for (int i = 0; i < totalPages; i++) {
                    pages[i] = i + 1;
                }
            }
        } else if (currentPage == totalPages) {
            System.out.println("currentPage == totalPages");
            if (totalPages >= 5) {
                System.out.println("if");
                int j = 4;
                for (int i = 0; i <= 4; i++) {
                    pages[i] = currentPage - j--;
                }
            } else {
                System.out.println("else");
                int j = 3;
                for (int i = 0; i <= totalPages; i++) {
                    pages[i] = currentPage - j--;
                }
            }
        } else if ((currentPage - 2) >= 1 && (currentPage + 2) <= totalPages) {
            System.out.println("((currentPage - 2) >= 1 && (currentPage + 2) <= totalPages)");
            for (int i = 0; i <= 4; i++) {
                pages[i] = currentPage - 2 + i;
            }
        } else if (currentPage == totalPages - 1) {
            System.out.println("currentPage == totalPages - 1");
            for (int i = 0; i <= 4; i++) {
                pages[i] = currentPage - 3 + i;
            }
        }

        return pages;
    }
}

package ebhor.pagination;

public class Pagination {

public static int[] getPageNos(int currentPage, int totalPages) {

int[] pages = new int[5];

if (currentPage <= 2) {

System.out.println("currentPage <=2");

if (totalPages >= 5) {

System.out.println("if");

for (int i = 0; i <= 4; i++) {

pages[i] = i + 1;

}

} else {

System.out.println("else");

for (int i = 0; i < totalPages; i++) {

pages[i] = i + 1;

}

} else if (currentPage == totalPages) {

System.out.println("currentPage == totalPages");

if (totalPages >= 5) {

System.out.println("if");

int j = 4;

for (int i = 0; i <= 4; i++) {

pages[i] = currentPage - j--;

}

} else {

System.out.println("else");

int j = 3;

for (int i = 0; i <= totalPages; i++) {

pages[i] = currentPage - j--;

}

} else if ((currentPage - 2) >= 1 && (currentPage + 2) <= totalPages) {

System.out.println("((currentPage - 2) >= 1 && (currentPage + 2) <= totalPages)");

for (int i = 0; i <= 4; i++) {

pages[i] = currentPage - 2 + i;

}

} else if (currentPage == totalPages - 1) {

System.out.println("currentPage == totalPages - 1");

for (int i = 0; i <= 4; i++) {

pages[i] = currentPage - 3 + i;

}

return pages;

}

Pagination Download

Registration Form in Java Swing with MySql Database

Registration Form in Java Swing is covered in this Post.

To develop this project we used NetBeans IDE.

Steps to develop Registration Form in Java Swing is as below

Create User Interface (UI) Using JFrame
Collect all data in Model sent from UI
Validate and Process Received data
Saving data to MySql Database

Here we have added three external Jar files

mysql-connector-jar-5.1.14-bin.jar – To connect Java program with MySql Database
jBCrypt-0.4.jar – To encrypt password
jdatepicker-1.3.4.jar– To include date picker in JFrame

To Develop Registration form we are considering example of Student.

We will create basic interface to collect student data in JFrame.

Our Final UI JFrame will as below

1 Create User Interface using JFrame

A. Create a basic structure for frame

In main method we created RegisterFrame class object.

set title, visibility, specified frame coordinated and height and width with bounds and other properties.

Created constructor RegisterFrame() to create and initialize frame components (JLable, JTextBox, JButton, …) .

Method setBounds() is used to set location, width and height of components.

addComponents() is used to add components to Container.

package ebhor.frame;

import javax.swing.JFrame;

public class RegisterFrame extends JFrame {

    public RegisterFrame() {

    }

    public void setBounds() {

    }

    public void addComponents() {

    }

    public static void main(String[] args) {
        RegisterFrame frame = new RegisterFrame();
        frame.setTitle("Student Register Form");
        frame.setVisible(true);
        frame.setBounds(500, 100, 500, 700);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(true);

    }

}

package ebhor.frame;

import javax.swing.JFrame;

public class RegisterFrame extends JFrame {

public RegisterFrame() {

}

public void setBounds() {

}

public void addComponents() {

}

public static void main(String[] args) {

RegisterFrame frame = new RegisterFrame();

frame.setTitle("Student Register Form");

frame.setVisible(true);

frame.setBounds(500, 100, 500, 700);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setResizable(true);

}

Output of above code is as below

JFrame Basic Size — Fig: JFrame height and width

This is basic layout for our Registration form.

B. Adding Components to JFrame

Components JLabel, JTextField, JRadioButton, JPasswordField, JCombobox, JButton etc are used here.

To select Date from Date Picker additional Jar jdatepicker-1.3.4.jar is added to project.

B Add the basic component in JFrame

Components are Declare as Instance variable
Objects of components are created inside Default Constructor
setBounds() is used to set position ,width and height of components.
addComponents() is used to add components in Container.
addActionListener() is used to add action listener on registerButton.
actionPerformed() is over ridden to handle event

Last two steps are handled later on.

package ebhor.frame;

import java.awt.Container;
import java.awt.Font;
import javax.swing.*;

public class RegisterFrame extends JFrame {

    JLabel message;
    JLabel nameLabel, dobLabel, genderLabel, dobFormat;
    JTextField nameField;
    JRadioButton genderMale, genderFemale;
    ButtonGroup genderGroup;

    JLabel mailIdLabel, mobileNoLabel;
    JTextField mailIdField, mobileNoField;

    JLabel passwordLabel, rePasswordLabel;
    JPasswordField passwordField, rePasswordField;

    JLabel programLabel;
    JComboBox<String> programList;

    JLabel branchLabel, semesterLabel;
    JComboBox<String> branchList;
    JComboBox<Integer> semesterList;

    JButton registerButton;
    Container container;

    public RegisterFrame() {
        message = new JLabel("Register a new Student");
        message.setFont(new Font("Courier", Font.BOLD, 20));
        nameLabel = new JLabel("Name");
        nameField = new JTextField();

        dobLabel = new JLabel("DOB");

        genderLabel = new JLabel("Gender");
        genderMale = new JRadioButton("Male", true);
        genderFemale = new JRadioButton("Female");
        genderGroup = new ButtonGroup();
        genderGroup.add(genderMale);
        genderGroup.add(genderFemale);

        mailIdLabel = new JLabel("Mail Id");
        mailIdField = new JTextField();

        mobileNoLabel = new JLabel("Mobile No");
        mobileNoField = new JTextField();

        passwordLabel = new JLabel("Password");
        passwordField = new JPasswordField();

        rePasswordLabel = new JLabel("Re Password");
        rePasswordField = new JPasswordField();

        programLabel = new JLabel("Courses");
        programList = new JComboBox<String>();

        programList.addItem("ME/M Tect");
        programList.addItem("BE/B Tect");
        programList.addItem("Diploma");

        branchLabel = new JLabel("Branch");
        branchList = new JComboBox<String>();

        branchList.addItem("Computer Science and Engineering");
        branchList.addItem("Electronics and Telecommunications");
        branchList.addItem("Information Technology");
        branchList.addItem("Electrical Engineering");
        branchList.addItem("Electrical and Electronics Engineering");
        branchList.addItem("Civil Engineering");

        semesterLabel = new JLabel("Semester");
        semesterList = new JComboBox<>();
        semesterList.addItem(1);
        semesterList.addItem(2);
        semesterList.addItem(3);
        semesterList.addItem(4);
        semesterList.addItem(5);
        semesterList.addItem(6);
        semesterList.addItem(7);
        semesterList.addItem(8);

        registerButton = new JButton("Register");
        container = getContentPane();
        container.setLayout(null);
        setBounds();
        addComponents();

    }

    public void setBounds() {
        message.setBounds(50, 10, 600, 30);
        nameLabel.setBounds(50, 60, 100, 30);
        nameField.setBounds(130, 60, 200, 30);

        dobLabel.setBounds(50, 110, 100, 30);

        genderLabel.setBounds(50, 160, 100, 30);
        genderMale.setBounds(130, 160, 100, 30);
        genderFemale.setBounds(240, 160, 100, 30);

        mailIdLabel.setBounds(50, 210, 100, 30);
        mailIdField.setBounds(130, 210, 200, 30);

        mobileNoLabel.setBounds(50, 260, 100, 30);
        mobileNoField.setBounds(130, 260, 200, 30);

        passwordLabel.setBounds(50, 310, 100, 30);
        passwordField.setBounds(130, 310, 200, 30);

        rePasswordLabel.setBounds(50, 360, 100, 30);
        rePasswordField.setBounds(130, 360, 200, 30);

        programLabel.setBounds(50, 410, 100, 30);
        programList.setBounds(130, 410, 200, 30);

        branchLabel.setBounds(50, 460, 100, 30);
        branchList.setBounds(130, 460, 200, 30);

        semesterLabel.setBounds(50, 510, 100, 30);
        semesterList.setBounds(130, 510, 200, 30);

        registerButton.setBounds(130, 550, 200, 30);
    }

    public void addComponents() {
        container.add(message);
        container.add(nameLabel);
        container.add(nameField);
        container.add(dobLabel);
        container.add(genderLabel);
        container.add(genderMale);
        container.add(genderFemale);
        container.add(mailIdLabel);
        container.add(mailIdField);
        container.add(mobileNoLabel);
        container.add(mobileNoField);
        container.add(passwordLabel);
        container.add(passwordField);
        container.add(rePasswordLabel);
        container.add(rePasswordField);
        container.add(programLabel);
        container.add(programList);
        container.add(branchLabel);
        container.add(branchList);
        container.add(semesterLabel);
        container.add(semesterList);
        container.add(registerButton);
    }

    public static void main(String[] args) {
        RegisterFrame frame = new RegisterFrame();
        frame.setTitle("Student Register Form");
        frame.setVisible(true);
        frame.setBounds(500, 100, 500, 700);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(true);

    }

}

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package ebhor.frame;

import java.awt.Container;

import java.awt.Font;

import javax.swing.*;

public class RegisterFrame extends JFrame {

JLabel message;

JLabel nameLabel, dobLabel, genderLabel, dobFormat;

JTextField nameField;

JRadioButton genderMale, genderFemale;

ButtonGroup genderGroup;

JLabel mailIdLabel, mobileNoLabel;

JTextField mailIdField, mobileNoField;

JLabel passwordLabel, rePasswordLabel;

JPasswordField passwordField, rePasswordField;

JLabel programLabel;

JComboBox<String> programList;

JLabel branchLabel, semesterLabel;

JComboBox<String> branchList;

JComboBox<Integer> semesterList;

JButton registerButton;

Container container;

public RegisterFrame() {

message = new JLabel("Register a new Student");

message.setFont(new Font("Courier", Font.BOLD, 20));

nameLabel = new JLabel("Name");

nameField = new JTextField();

dobLabel = new JLabel("DOB");

genderLabel = new JLabel("Gender");

genderMale = new JRadioButton("Male", true);

genderFemale = new JRadioButton("Female");

genderGroup = new ButtonGroup();

genderGroup.add(genderMale);

genderGroup.add(genderFemale);

mailIdLabel = new JLabel("Mail Id");

mailIdField = new JTextField();

mobileNoLabel = new JLabel("Mobile No");

mobileNoField = new JTextField();

passwordLabel = new JLabel("Password");

passwordField = new JPasswordField();

rePasswordLabel = new JLabel("Re Password");

rePasswordField = new JPasswordField();

programLabel = new JLabel("Courses");

programList = new JComboBox<String>();

programList.addItem("ME/M Tect");

programList.addItem("BE/B Tect");

programList.addItem("Diploma");

branchLabel = new JLabel("Branch");

branchList = new JComboBox<String>();

branchList.addItem("Computer Science and Engineering");

branchList.addItem("Electronics and Telecommunications");

branchList.addItem("Information Technology");

branchList.addItem("Electrical Engineering");

branchList.addItem("Electrical and Electronics Engineering");

branchList.addItem("Civil Engineering");

semesterLabel = new JLabel("Semester");

semesterList = new JComboBox<>();

semesterList.addItem(1);

semesterList.addItem(2);

semesterList.addItem(3);

semesterList.addItem(4);

semesterList.addItem(5);

semesterList.addItem(6);

semesterList.addItem(7);

semesterList.addItem(8);

registerButton = new JButton("Register");

container = getContentPane();

container.setLayout(null);

setBounds();

addComponents();

}

public void setBounds() {

message.setBounds(50, 10, 600, 30);

nameLabel.setBounds(50, 60, 100, 30);

nameField.setBounds(130, 60, 200, 30);

dobLabel.setBounds(50, 110, 100, 30);

genderLabel.setBounds(50, 160, 100, 30);

genderMale.setBounds(130, 160, 100, 30);

genderFemale.setBounds(240, 160, 100, 30);

mailIdLabel.setBounds(50, 210, 100, 30);

mailIdField.setBounds(130, 210, 200, 30);

mobileNoLabel.setBounds(50, 260, 100, 30);

mobileNoField.setBounds(130, 260, 200, 30);

passwordLabel.setBounds(50, 310, 100, 30);

passwordField.setBounds(130, 310, 200, 30);

rePasswordLabel.setBounds(50, 360, 100, 30);

rePasswordField.setBounds(130, 360, 200, 30);

programLabel.setBounds(50, 410, 100, 30);

programList.setBounds(130, 410, 200, 30);

branchLabel.setBounds(50, 460, 100, 30);

branchList.setBounds(130, 460, 200, 30);

semesterLabel.setBounds(50, 510, 100, 30);

semesterList.setBounds(130, 510, 200, 30);

registerButton.setBounds(130, 550, 200, 30);

}

public void addComponents() {

container.add(message);

container.add(nameLabel);

container.add(nameField);

container.add(dobLabel);

container.add(genderLabel);

container.add(genderMale);

container.add(genderFemale);

container.add(mailIdLabel);

container.add(mailIdField);

container.add(mobileNoLabel);

container.add(mobileNoField);

container.add(passwordLabel);

container.add(passwordField);

container.add(rePasswordLabel);

container.add(rePasswordField);

container.add(programLabel);

container.add(programList);

container.add(branchLabel);

container.add(branchList);

container.add(semesterLabel);

container.add(semesterList);

container.add(registerButton);

}

public static void main(String[] args) {

RegisterFrame frame = new RegisterFrame();

frame.setTitle("Student Register Form");

frame.setVisible(true);

frame.setBounds(500, 100, 500, 700);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setResizable(true);

}

After adding basic components it will create Frame as below

Adding Components in JFrame — Fig: Adding Basic Components in JFrame

C Add JDatePicker in JFrame

First check jdatepicker-1.3.4.jar is added in project

Imports for JDatePicker

import javax.swing.JFormattedTextField.AbstractFormatter;
import org.jdatepicker.impl.JDatePanelImpl;
import org.jdatepicker.impl.JDatePickerImpl;
import org.jdatepicker.impl.UtilDateModel;

import javax.swing.JFormattedTextField.AbstractFormatter;

import org.jdatepicker.impl.JDatePanelImpl;

import org.jdatepicker.impl.JDatePickerImpl;

import org.jdatepicker.impl.UtilDateModel;

Adding JDatePicker in constructor

 /*Adding JDatePicker date picker*/
        UtilDateModel model = new UtilDateModel();
        model.setDate(1999, 01, 02);
        model.setSelected(true);
        Properties p = new Properties();
        p.put("text.today", "Today");
        p.put("text.month", "Month");
        p.put("text.year", "Year");
        datePanel = new JDatePanelImpl(model, p);
        datePicker = new JDatePickerImpl(datePanel, new DateLabelFormatter());
        dobFormat = new JLabel("(yyyy-mm-dd)");
        /*End Date picker*/

/*Adding JDatePicker date picker*/

UtilDateModel model = new UtilDateModel();

model.setDate(1999, 01, 02);

model.setSelected(true);

Properties p = new Properties();

p.put("text.today", "Today");

p.put("text.month", "Month");

p.put("text.year", "Year");

datePanel = new JDatePanelImpl(model, p);

datePicker = new JDatePickerImpl(datePanel, new DateLabelFormatter());

dobFormat = new JLabel("(yyyy-mm-dd)");

/*End Date picker*/

complete code after adding JDatePicker

package ebhor.frame;

import java.awt.*;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Properties;
import javax.swing.*;
/*imports for JDatePicker*/
import javax.swing.JFormattedTextField.AbstractFormatter;
import org.jdatepicker.impl.JDatePanelImpl;
import org.jdatepicker.impl.JDatePickerImpl;
import org.jdatepicker.impl.UtilDateModel;

public class RegisterFrame extends JFrame {

    JLabel message;
    JLabel nameLabel, dobLabel, genderLabel, dobFormat;
    JTextField nameField;
    JRadioButton genderMale, genderFemale;
    ButtonGroup genderGroup;

    JLabel mailIdLabel, mobileNoLabel;
    JTextField mailIdField, mobileNoField;

    JLabel passwordLabel, rePasswordLabel;
    JPasswordField passwordField, rePasswordField;

    JLabel programLabel;
    JComboBox<String> programList;

    JLabel branchLabel, semesterLabel;
    JComboBox<String> branchList;
    JComboBox<Integer> semesterList;

    JButton registerButton;
    Container container;

    /*JDatePicker*/
    JDatePanelImpl datePanel;
    JDatePickerImpl datePicker;

    public RegisterFrame() {
        message = new JLabel("Register a new Student");
        message.setFont(new Font("Courier", Font.BOLD, 20));
        nameLabel = new JLabel("Name");
        nameField = new JTextField();

        dobLabel = new JLabel("DOB");
        //dobField = new JTextField();

        /*Adding JDatePicker date picker*/
        UtilDateModel model = new UtilDateModel();
        model.setDate(1999, 01, 02);
        model.setSelected(true);
        Properties p = new Properties();
        p.put("text.today", "Today");
        p.put("text.month", "Month");
        p.put("text.year", "Year");
        datePanel = new JDatePanelImpl(model, p);
        datePicker = new JDatePickerImpl(datePanel, new DateLabelFormatter());
        dobFormat = new JLabel("(yyyy-mm-dd)");
        /*End Date picker*/

        genderLabel = new JLabel("Gender");
        genderMale = new JRadioButton("Male", true);
        genderFemale = new JRadioButton("Female");
        genderGroup = new ButtonGroup();
        genderGroup.add(genderMale);
        genderGroup.add(genderFemale);

        mailIdLabel = new JLabel("Mail Id");
        mailIdField = new JTextField();

        mobileNoLabel = new JLabel("Mobile No");
        mobileNoField = new JTextField();

        passwordLabel = new JLabel("Password");
        passwordField = new JPasswordField();

        rePasswordLabel = new JLabel("Re Password");
        rePasswordField = new JPasswordField();

        programLabel = new JLabel("Courses");
        programList = new JComboBox<String>();

        programList.addItem("ME/M Tect");
        programList.addItem("BE/B Tect");
        programList.addItem("Diploma");

        branchLabel = new JLabel("Branch");
        branchList = new JComboBox<String>();

        branchList.addItem("Computer Science and Engineering");
        branchList.addItem("Electronics and Telecommunications");
        branchList.addItem("Information Technology");
        branchList.addItem("Electrical Engineering");
        branchList.addItem("Electrical and Electronics Engineering");
        branchList.addItem("Civil Engineering");

        semesterLabel = new JLabel("Semester");
        semesterList = new JComboBox<>();
        semesterList.addItem(1);
        semesterList.addItem(2);
        semesterList.addItem(3);
        semesterList.addItem(4);
        semesterList.addItem(5);
        semesterList.addItem(6);
        semesterList.addItem(7);
        semesterList.addItem(8);

        registerButton = new JButton("Register");
        container = getContentPane();
        container.setLayout(null);
        setBounds();
        addComponents();

    }

    public void setBounds() {
        message.setBounds(50, 10, 600, 30);
        nameLabel.setBounds(50, 60, 100, 30);
        nameField.setBounds(130, 60, 200, 30);

        dobLabel.setBounds(50, 110, 100, 30);
        /*JDatePicker*/
        datePicker.setBounds(130, 110, 200, 30);
        dobFormat.setBounds(350, 110, 200, 30);

        genderLabel.setBounds(50, 160, 100, 30);
        genderMale.setBounds(130, 160, 100, 30);
        genderFemale.setBounds(240, 160, 100, 30);

        mailIdLabel.setBounds(50, 210, 100, 30);
        mailIdField.setBounds(130, 210, 200, 30);

        mobileNoLabel.setBounds(50, 260, 100, 30);
        mobileNoField.setBounds(130, 260, 200, 30);

        passwordLabel.setBounds(50, 310, 100, 30);
        passwordField.setBounds(130, 310, 200, 30);

        rePasswordLabel.setBounds(50, 360, 100, 30);
        rePasswordField.setBounds(130, 360, 200, 30);

        programLabel.setBounds(50, 410, 100, 30);
        programList.setBounds(130, 410, 200, 30);

        branchLabel.setBounds(50, 460, 100, 30);
        branchList.setBounds(130, 460, 200, 30);

        semesterLabel.setBounds(50, 510, 100, 30);
        semesterList.setBounds(130, 510, 200, 30);

        registerButton.setBounds(130, 550, 200, 30);
    }

    public void addComponents() {
        container.add(message);
        container.add(nameLabel);
        container.add(nameField);
        container.add(dobLabel);
        /*JDatePicker*/
        container.add(datePicker);
        container.add(dobFormat);
        container.add(genderLabel);
        container.add(genderMale);
        container.add(genderFemale);
        container.add(mailIdLabel);
        container.add(mailIdField);
        container.add(mobileNoLabel);
        container.add(mobileNoField);
        container.add(passwordLabel);
        container.add(passwordField);
        container.add(rePasswordLabel);
        container.add(rePasswordField);
        container.add(programLabel);
        container.add(programList);
        container.add(branchLabel);
        container.add(branchList);
        container.add(semesterLabel);
        container.add(semesterList);
        container.add(registerButton);
    }

    public static void main(String[] args) {
        RegisterFrame frame = new RegisterFrame();
        frame.setTitle("Student Register Form");
        frame.setVisible(true);
        frame.setBounds(500, 100, 500, 700);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(true);

    }

    /*JDate Picker drop down*/
    public class DateLabelFormatter extends AbstractFormatter {

        private String datePattern = "yyyy-MM-dd";
        private SimpleDateFormat dateFormatter = new SimpleDateFormat(datePattern);

        @Override
        public Object stringToValue(String text) throws ParseException {
            return dateFormatter.parseObject(text);
        }

        @Override
        public String valueToString(Object value) throws ParseException {
            if (value != null) {
                Calendar cal = (Calendar) value;
                return dateFormatter.format(cal.getTime());
            }

            return "";
        }

    }
}

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package ebhor.frame;

import java.awt.*;

import java.text.ParseException;

import java.text.SimpleDateFormat;

import java.util.Calendar;

import java.util.Properties;

import javax.swing.*;

/*imports for JDatePicker*/

import javax.swing.JFormattedTextField.AbstractFormatter;

import org.jdatepicker.impl.JDatePanelImpl;

import org.jdatepicker.impl.JDatePickerImpl;

import org.jdatepicker.impl.UtilDateModel;

public class RegisterFrame extends JFrame {

JLabel message;

JLabel nameLabel, dobLabel, genderLabel, dobFormat;

JTextField nameField;

JRadioButton genderMale, genderFemale;

ButtonGroup genderGroup;

JLabel mailIdLabel, mobileNoLabel;

JTextField mailIdField, mobileNoField;

JLabel passwordLabel, rePasswordLabel;

JPasswordField passwordField, rePasswordField;

JLabel programLabel;

JComboBox<String> programList;

JLabel branchLabel, semesterLabel;

JComboBox<String> branchList;

JComboBox<Integer> semesterList;

JButton registerButton;

Container container;

/*JDatePicker*/

JDatePanelImpl datePanel;

JDatePickerImpl datePicker;

public RegisterFrame() {

message = new JLabel("Register a new Student");

message.setFont(new Font("Courier", Font.BOLD, 20));

nameLabel = new JLabel("Name");

nameField = new JTextField();

dobLabel = new JLabel("DOB");

//dobField = new JTextField();

/*Adding JDatePicker date picker*/

UtilDateModel model = new UtilDateModel();

model.setDate(1999, 01, 02);

model.setSelected(true);

Properties p = new Properties();

p.put("text.today", "Today");

p.put("text.month", "Month");

p.put("text.year", "Year");

datePanel = new JDatePanelImpl(model, p);

datePicker = new JDatePickerImpl(datePanel, new DateLabelFormatter());

dobFormat = new JLabel("(yyyy-mm-dd)");

/*End Date picker*/

genderLabel = new JLabel("Gender");

genderMale = new JRadioButton("Male", true);

genderFemale = new JRadioButton("Female");

genderGroup = new ButtonGroup();

genderGroup.add(genderMale);

genderGroup.add(genderFemale);

mailIdLabel = new JLabel("Mail Id");

mailIdField = new JTextField();

mobileNoLabel = new JLabel("Mobile No");

mobileNoField = new JTextField();

passwordLabel = new JLabel("Password");

passwordField = new JPasswordField();

rePasswordLabel = new JLabel("Re Password");

rePasswordField = new JPasswordField();

programLabel = new JLabel("Courses");

programList = new JComboBox<String>();

programList.addItem("ME/M Tect");

programList.addItem("BE/B Tect");

programList.addItem("Diploma");

branchLabel = new JLabel("Branch");

branchList = new JComboBox<String>();

branchList.addItem("Computer Science and Engineering");

branchList.addItem("Electronics and Telecommunications");

branchList.addItem("Information Technology");

branchList.addItem("Electrical Engineering");

branchList.addItem("Electrical and Electronics Engineering");

branchList.addItem("Civil Engineering");

semesterLabel = new JLabel("Semester");

semesterList = new JComboBox<>();

semesterList.addItem(1);

semesterList.addItem(2);

semesterList.addItem(3);

semesterList.addItem(4);

semesterList.addItem(5);

semesterList.addItem(6);

semesterList.addItem(7);

semesterList.addItem(8);

registerButton = new JButton("Register");

container = getContentPane();

container.setLayout(null);

setBounds();

addComponents();

}

public void setBounds() {

message.setBounds(50, 10, 600, 30);

nameLabel.setBounds(50, 60, 100, 30);

nameField.setBounds(130, 60, 200, 30);

dobLabel.setBounds(50, 110, 100, 30);

/*JDatePicker*/

datePicker.setBounds(130, 110, 200, 30);

dobFormat.setBounds(350, 110, 200, 30);

genderLabel.setBounds(50, 160, 100, 30);

genderMale.setBounds(130, 160, 100, 30);

genderFemale.setBounds(240, 160, 100, 30);

mailIdLabel.setBounds(50, 210, 100, 30);

mailIdField.setBounds(130, 210, 200, 30);

mobileNoLabel.setBounds(50, 260, 100, 30);

mobileNoField.setBounds(130, 260, 200, 30);

passwordLabel.setBounds(50, 310, 100, 30);

passwordField.setBounds(130, 310, 200, 30);

rePasswordLabel.setBounds(50, 360, 100, 30);

rePasswordField.setBounds(130, 360, 200, 30);

programLabel.setBounds(50, 410, 100, 30);

programList.setBounds(130, 410, 200, 30);

branchLabel.setBounds(50, 460, 100, 30);

branchList.setBounds(130, 460, 200, 30);

semesterLabel.setBounds(50, 510, 100, 30);

semesterList.setBounds(130, 510, 200, 30);

registerButton.setBounds(130, 550, 200, 30);

}

public void addComponents() {

container.add(message);

container.add(nameLabel);

container.add(nameField);

container.add(dobLabel);

/*JDatePicker*/

container.add(datePicker);

container.add(dobFormat);

container.add(genderLabel);

container.add(genderMale);

container.add(genderFemale);

container.add(mailIdLabel);

container.add(mailIdField);

container.add(mobileNoLabel);

container.add(mobileNoField);

container.add(passwordLabel);

container.add(passwordField);

container.add(rePasswordLabel);

container.add(rePasswordField);

container.add(programLabel);

container.add(programList);

container.add(branchLabel);

container.add(branchList);

container.add(semesterLabel);

container.add(semesterList);

container.add(registerButton);

}

public static void main(String[] args) {

RegisterFrame frame = new RegisterFrame();

frame.setTitle("Student Register Form");

frame.setVisible(true);

frame.setBounds(500, 100, 500, 700);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setResizable(true);

}

/*JDate Picker drop down*/

public class DateLabelFormatter extends AbstractFormatter {

private String datePattern = "yyyy-MM-dd";

private SimpleDateFormat dateFormatter = new SimpleDateFormat(datePattern);

@Override

public Object stringToValue(String text) throws ParseException {

return dateFormatter.parseObject(text);

}

@Override

public String valueToString(Object value) throws ParseException {

if (value != null) {

Calendar cal = (Calendar) value;

return dateFormatter.format(cal.getTime());

}

return "";

}

DateLabelFormatter class is used to show date selector.

JDatePicker Example — Fig: JDatePicker Addition in JFrame

It will complete our UI

2 Collect all data in Model sent from UI

To collect data Register button is clicked and all data from text box and other input fields are collected and set to student Model.

Lets First See student model Students.java

This class contains basic fields of student, constructors, getter and setter methods and to string method.

package ebhor.model;

import java.io.Serializable;
import java.sql.Date;
import java.sql.Timestamp;

public class Student implements  Serializable{

    private long id;
    private String name;
    private Date dob;
    private String gender;
    private String mailId;
    private String mobileNo;
    private String password;
    private String rePassword;
    private String encPassword;//Encrypted password
    private String program;
    private String branch;
    private int semester;
    private Timestamp addDate;

    public Student() {
    }

    public Student(String name, Date dob, String gender, String mailId, String mobileNo, String password, String rePassword, String program, String branch, int semester) {
        this.name = name;
        this.dob = dob;
        this.gender = gender;
        this.mailId = mailId;
        this.mobileNo = mobileNo;
        this.password = password;
        this.rePassword = rePassword;
        this.program = program;
        this.branch = branch;
        this.semester = semester;
    }

    public Student(long id, String name, Date dob, String gender, String mailId, String mobileNo, String password, String rePassword, String program, String branch, int semester, Timestamp addDate) {
        this.id = id;
        this.name = name;
        this.dob = dob;
        this.gender = gender;
        this.mailId = mailId;
        this.mobileNo = mobileNo;
        this.password = password;
        this.rePassword = rePassword;
        this.program = program;
        this.branch = branch;
        this.semester = semester;
        this.addDate = addDate;
    }

    @Override
    public String toString() {
        return "Student{" + "id=" + id + ", name=" + name + ", dob=" + dob + ", gender=" + gender + ", mailId=" + mailId + ", mobileNo=" + mobileNo + ", password=" + password + ", rePassword=" + rePassword + ", program=" + program + ", branch=" + branch + ", semester=" + semester + ", addDate=" + addDate + '}';
    }

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Date getDob() {
        return dob;
    }

    public void setDob(Date dob) {
        this.dob = dob;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public String getMailId() {
        return mailId;
    }

    public void setMailId(String mailId) {
        this.mailId = mailId;
    }

    public String getMobileNo() {
        return mobileNo;
    }

    public void setMobileNo(String mobileNo) {
        this.mobileNo = mobileNo;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getRePassword() {
        return rePassword;
    }

    public void setRePassword(String rePassword) {
        this.rePassword = rePassword;
    }

    public String getProgram() {
        return program;
    }

    public void setProgram(String program) {
        this.program = program;
    }

    public String getBranch() {
        return branch;
    }

    public void setBranch(String branch) {
        this.branch = branch;
    }

    public int getSemester() {
        return semester;
    }

    public void setSemester(int semester) {
        this.semester = semester;
    }

    public Timestamp getAddDate() {
        return addDate;
    }

    public void setAddDate(Timestamp addDate) {
        this.addDate = addDate;
    }

    public String getEncPassword() {
        return encPassword;
    }

    public void setEncPassword(String encPassword) {
        this.encPassword = encPassword;
    }

}

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package ebhor.model;

import java.io.Serializable;

import java.sql.Date;

import java.sql.Timestamp;

public class Student implements Serializable{

private long id;

private String name;

private Date dob;

private String gender;

private String mailId;

private String mobileNo;

private String password;

private String rePassword;

private String encPassword;//Encrypted password

private String program;

private String branch;

private int semester;

private Timestamp addDate;

public Student() {

}

public Student(String name, Date dob, String gender, String mailId, String mobileNo, String password, String rePassword, String program, String branch, int semester) {

this.name = name;

this.dob = dob;

this.gender = gender;

this.mailId = mailId;

this.mobileNo = mobileNo;

this.password = password;

this.rePassword = rePassword;

this.program = program;

this.branch = branch;

this.semester = semester;

}

public Student(long id, String name, Date dob, String gender, String mailId, String mobileNo, String password, String rePassword, String program, String branch, int semester, Timestamp addDate) {

this.id = id;

this.name = name;

this.dob = dob;

this.gender = gender;

this.mailId = mailId;

this.mobileNo = mobileNo;

this.password = password;

this.rePassword = rePassword;

this.program = program;

this.branch = branch;

this.semester = semester;

this.addDate = addDate;

}

@Override

public String toString() {

return "Student{" + "id=" + id + ", name=" + name + ", dob=" + dob + ", gender=" + gender + ", mailId=" + mailId + ", mobileNo=" + mobileNo + ", password=" + password + ", rePassword=" + rePassword + ", program=" + program + ", branch=" + branch + ", semester=" + semester + ", addDate=" + addDate + '}';

}

public long getId() {

return id;

}

public void setId(long id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public Date getDob() {

return dob;

}

public void setDob(Date dob) {

this.dob = dob;

}

public String getGender() {

return gender;

}

public void setGender(String gender) {

this.gender = gender;

}

public String getMailId() {

return mailId;

}

public void setMailId(String mailId) {

this.mailId = mailId;

}

public String getMobileNo() {

return mobileNo;

}

public void setMobileNo(String mobileNo) {

this.mobileNo = mobileNo;

}

public String getPassword() {

return password;

}

public void setPassword(String password) {

this.password = password;

}

public String getRePassword() {

return rePassword;

}

public void setRePassword(String rePassword) {

this.rePassword = rePassword;

}

public String getProgram() {

return program;

}

public void setProgram(String program) {

this.program = program;

}

public String getBranch() {

return branch;

}

public void setBranch(String branch) {

this.branch = branch;

}

public int getSemester() {

return semester;

}

public void setSemester(int semester) {

this.semester = semester;

}

public Timestamp getAddDate() {

return addDate;

}

public void setAddDate(Timestamp addDate) {

this.addDate = addDate;

}

public String getEncPassword() {

return encPassword;

}

public void setEncPassword(String encPassword) {

this.encPassword = encPassword;

}

Adding following code to RegisterFrame.java

ActionLister is added for registerButton
actionPerformed() is overridden to handle click event on register button

Based on genderFemale and genderMale is selected gender variable.is set based on that.

Similar way storing programName, branchName and semesterName from respective dropdown list.

To get value from JDatePicker datePicker.getJFormattedTextField().getText() is used.

It returns value in string to convert string date to java.sql.date Date.valueOf(dobString) is used.

public void addActionListener() {
        registerButton.addActionListener(this);
    }

    @Override
    public void actionPerformed(ActionEvent e) {

        if (e.getSource() == registerButton) { 
            System.out.println("Register Button Clicked");
            String gender = null;
            if (genderFemale.isSelected()) {
                gender = "Female";
            }
            if (genderMale.isSelected()) {
                gender = "Male";
            }
            String programName = programList.getSelectedItem().toString();
            String branchName = branchList.getSelectedItem().toString();
            int semesterNo = Integer.parseInt(semesterList.getSelectedItem().toString());
            String dobString = datePicker.getJFormattedTextField().getText();
            if (dobString.isEmpty()) {
                JOptionPane.showMessageDialog(null, "Date of Birth is Empty");
                return;
            }
            Date dob = null;
            try {
                dob = Date.valueOf(dobString);
            } catch (IllegalArgumentException ex) {
                System.out.println("Exception " + ex);
                JOptionPane.showMessageDialog(null, "Date of birth format is in correct");
                return;
            }
            System.out.println("name " + nameField.getText() + " dob " + dobString
                    + " gender " + gender + " mailid " + mailIdField.getText()
                    + " mobileNo " + mobileNoField.getText() + " password " + passwordField.getText()
                    + " rePassword " + rePasswordField.getText() + " branch " + branchName
                    + " semester " + semesterNo);

            Student student = new Student(nameField.getText(), dob, gender, mailIdField.getText(), mobileNoField.getText(), passwordField.getText(), rePasswordField.getText(), programName, branchName, semesterNo);
        }
    }

public void addActionListener() {

registerButton.addActionListener(this);

}

@Override

public void actionPerformed(ActionEvent e) {

if (e.getSource() == registerButton) {

System.out.println("Register Button Clicked");

String gender = null;

if (genderFemale.isSelected()) {

gender = "Female";

}

if (genderMale.isSelected()) {

gender = "Male";

}

String programName = programList.getSelectedItem().toString();

String branchName = branchList.getSelectedItem().toString();

int semesterNo = Integer.parseInt(semesterList.getSelectedItem().toString());

String dobString = datePicker.getJFormattedTextField().getText();

if (dobString.isEmpty()) {

JOptionPane.showMessageDialog(null, "Date of Birth is Empty");

return;

}

Date dob = null;

try {

dob = Date.valueOf(dobString);

} catch (IllegalArgumentException ex) {

System.out.println("Exception " + ex);

JOptionPane.showMessageDialog(null, "Date of birth format is in correct");

return;

}

System.out.println("name " + nameField.getText() + " dob " + dobString

+ " gender " + gender + " mailid " + mailIdField.getText()

+ " mobileNo " + mobileNoField.getText() + " password " + passwordField.getText()

+ " rePassword " + rePasswordField.getText() + " branch " + branchName

+ " semester " + semesterNo);

Student student = new Student(nameField.getText(), dob, gender, mailIdField.getText(), mobileNoField.getText(), passwordField.getText(), rePasswordField.getText(), programName, branchName, semesterNo);

}

3 Validate and Process Received data

Received data is stored in Student object.

We have already validated dob field.

Other fields are validated in Validation.java

All fields are checked for Empty.
Name length must be more than 4 and less than 20
Validation for Mail id
Mobile Number must be 10 digits long
Password must be between 8 to 20 characters
Password must contain One digit one upper case letter and special symbol
RePassword and password must match

package ebhor.frame;

import ebhor.model.Student;
import java.util.ArrayList;
import java.util.List;


public class Validation {

    public List<String> validateRegistration(Student student) {
        ArrayList<String> err = new ArrayList<String>();
        if (student.getName().isEmpty()) {
            err.add("Name can not be empty");
        } else if (student.getName().length() < 4) {
            err.add("Name is too short");
        } else if (student.getName().length() > 50) {
            err.add("Name is too long");
        } else if (!isString(student.getName())) {
            err.add("Only characters allowed in name");
        }
        if (student.getMailId().isEmpty()) {
            err.add("MailId can not be empty");
        } else if (!isValidEmailAddress(student.getMailId())) {
            err.add("MailId is not valid");
        }
        if (student.getMobileNo().isEmpty()) {
            err.add("Mobile Number can not be empty");
        } else if (student.getMobileNo().length() != 10) {
            err.add("Mobile Number must be 10 digit long");
        } else if (!isDigit(student.getMobileNo())) {
            err.add("Mobile Numbers must have only digits");
        }
        if (student.getPassword().isEmpty()) {
            err.add("Password not be empty");
        } else if (student.getPassword().length() < 8) {
            err.add("Password is too short");
        } else if (student.getPassword().length() > 20) {
            err.add("Password is too long");
        } else if (!isStrongPassword(student.getPassword())) {
            err.add("Enter Strong Password");
        }
        if (student.getRePassword().isEmpty()) {
            err.add("Re Password can not be empty");
        } else if (student.getRePassword().length() < 8) {
            err.add("Re Password is too short");
        } else if (student.getRePassword().length() > 20) {
            err.add("Re Password is too long");
        }
        if (!student.getPassword().equals(student.getRePassword())) {
            err.add("Both passwords are not matching");
        }
        return err;
    }


    public boolean isValidEmailAddress(String email) {
        String ePattern = "^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\])|(([a-zA-Z\\-0-9]+\\.)+[a-zA-Z]{2,}))$";
        java.util.regex.Pattern p = java.util.regex.Pattern.compile(ePattern);
        java.util.regex.Matcher m = p.matcher(email);
        return m.matches();
    }

    //https://stackoverflow.com/a/15806080/876739
    public boolean isString(String name) {
        String ePattern = "^[\\p{L} '-]+$";
        java.util.regex.Pattern p = java.util.regex.Pattern.compile(ePattern);
        java.util.regex.Matcher m = p.matcher(name);
        return m.matches();
    }

//https://stackoverflow.com/a/3802238/876739
    public boolean isStrongPassword(String text) {
        String ePattern = "^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%^&+=])(?=\\S+$).{8,}$";
        java.util.regex.Pattern p = java.util.regex.Pattern.compile(ePattern);
        java.util.regex.Matcher m = p.matcher(text);
        return m.matches();
    }
//https://stackoverflow.com/a/34253764/876739

    public boolean isDigit(String mobileNo) {
        boolean digits = mobileNo.chars().allMatch(Character::isDigit);
        return digits;
    }
}

package ebhor.frame;

import ebhor.model.Student;

import java.util.ArrayList;

import java.util.List;

public class Validation {

public List<String> validateRegistration(Student student) {

ArrayList<String> err = new ArrayList<String>();

if (student.getName().isEmpty()) {

err.add("Name can not be empty");

} else if (student.getName().length() < 4) {

err.add("Name is too short");

} else if (student.getName().length() > 50) {

err.add("Name is too long");

} else if (!isString(student.getName())) {

err.add("Only characters allowed in name");

}

if (student.getMailId().isEmpty()) {

err.add("MailId can not be empty");

} else if (!isValidEmailAddress(student.getMailId())) {

err.add("MailId is not valid");

}

if (student.getMobileNo().isEmpty()) {

err.add("Mobile Number can not be empty");

} else if (student.getMobileNo().length() != 10) {

err.add("Mobile Number must be 10 digit long");

} else if (!isDigit(student.getMobileNo())) {

err.add("Mobile Numbers must have only digits");

}

if (student.getPassword().isEmpty()) {

err.add("Password not be empty");

} else if (student.getPassword().length() < 8) {

err.add("Password is too short");

} else if (student.getPassword().length() > 20) {

err.add("Password is too long");

} else if (!isStrongPassword(student.getPassword())) {

err.add("Enter Strong Password");

}

if (student.getRePassword().isEmpty()) {

err.add("Re Password can not be empty");

} else if (student.getRePassword().length() < 8) {

err.add("Re Password is too short");

} else if (student.getRePassword().length() > 20) {

err.add("Re Password is too long");

}

if (!student.getPassword().equals(student.getRePassword())) {

err.add("Both passwords are not matching");

}

return err;

}

public boolean isValidEmailAddress(String email) {

String ePattern = "^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-][email protected]((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\])|(([a-zA-Z\\-0-9]+\\.)+[a-zA-Z]{2,}))$";

java.util.regex.Pattern p = java.util.regex.Pattern.compile(ePattern);

java.util.regex.Matcher m = p.matcher(email);

return m.matches();

}

//https://stackoverflow.com/a/15806080/876739

public boolean isString(String name) {

String ePattern = "^[\\p{L} '-]+$";

java.util.regex.Pattern p = java.util.regex.Pattern.compile(ePattern);

java.util.regex.Matcher m = p.matcher(name);

return m.matches();

}

//https://stackoverflow.com/a/3802238/876739

public boolean isStrongPassword(String text) {

String ePattern = "^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%^&+=])(?=\\S+$).{8,}$";

java.util.regex.Pattern p = java.util.regex.Pattern.compile(ePattern);

java.util.regex.Matcher m = p.matcher(text);

return m.matches();

}

//https://stackoverflow.com/a/34253764/876739

public boolean isDigit(String mobileNo) {

boolean digits = mobileNo.chars().allMatch(Character::isDigit);

return digits;

}

Creating object of validation and and checking for errors if error occurs then it is shown using showMessageDialog().

Student student = new Student(nameField.getText(), dob, gender, mailIdField.getText(), mobileNoField.getText(), passwordField.getText(), rePasswordField.getText(), programName, branchName, semesterNo);
            student.setEncPassword(BCrypt.hashpw(student.getPassword(), BCrypt.gensalt()));
            Validation v = new Validation();
            java.util.List<String> errors = v.validateRegistration(student);
            if (errors.size() > 0) {
                JOptionPane.showMessageDialog(null, errors.toArray());
                return;
            }

student.setEncPassword(BCrypt.hashpw(student.getPassword(), BCrypt.gensalt()));

Validation v = new Validation();

java.util.List<String> errors = v.validateRegistration(student);

if (errors.size() > 0) {

JOptionPane.showMessageDialog(null, errors.toArray());

return;

}

Processing Data

Processing data is done before and after validation

Based on male and female JRadioButton we assigned male or female to gender variable.
Get Dob from JDatePicker as string and then converted again to java.sql.Date.
BCrypt is used to encrypt password and set to encPassword().

4 Saving data to MySql Database

Validated and processed data and stored in Student object.

To save data of student object first create student table as given below.

CREATE TABLE student
  (
     id        BIGINT(20) UNSIGNED NOT NULL auto_increment,
     name      VARCHAR(200),
     dob       DATE,
     gender    VARCHAR(10),
     mailid    VARCHAR(100),
     mobile_no VARCHAR(12),
     password  VARCHAR(200),
     program    VARCHAR(100),
     branch    VARCHAR(100),
     semester  INT(2),
     add_date   TIMESTAMP DEFAULT CURRENT_TIMESTAMP(),
     PRIMARY KEY (id),
     UNIQUE KEY (mailid),
     UNIQUE KEY (mobile_no)
  )
engine=innodb
DEFAULT charset=utf8;

CREATE TABLE student

(

id BIGINT(20) UNSIGNED NOT NULL auto_increment,

name VARCHAR(200),

dob DATE,

gender VARCHAR(10),

mailid VARCHAR(100),

mobile_no VARCHAR(12),

password VARCHAR(200),

program VARCHAR(100),

branch VARCHAR(100),

semester INT(2),

add_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP(),

PRIMARY KEY (id),

UNIQUE KEY (mailid),

UNIQUE KEY (mobile_no)

)

engine=innodb

DEFAULT charset=utf8;

ConnectionFactory.java

This file is used to connect java with database and returns the connection object.

Database name :ebhor
Username: ebhor_user
Password: 21V6

package ebhor.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class ConnectionFactory {

    public static Connection getConnection() {
        Connection c = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            c = DriverManager.getConnection("jdbc:mysql://localhost:3306/ebhor?useUnicode=true&characterEncoding=UTF-8", "ebhor_user", "21V6");
        } catch (ClassNotFoundException e) {
            System.out.println("ClassNotFoundException " + e);
        } catch (SQLException e) {
            System.out.println("SQLException " + e);
        }
        return c;
    }
}

package ebhor.dao;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

public class ConnectionFactory {

public static Connection getConnection() {

Connection c = null;

try {

Class.forName("com.mysql.jdbc.Driver");

c = DriverManager.getConnection("jdbc:mysql://localhost:3306/ebhor?useUnicode=true&characterEncoding=UTF-8", "ebhor_user", "21V6");

} catch (ClassNotFoundException e) {

System.out.println("ClassNotFoundException " + e);

} catch (SQLException e) {

System.out.println("SQLException " + e);

}

return c;

}

RegisterDAO.java

registerStudent() takes a student object and save each field to database using java preparedStatement();

package ebhor.dao;

import com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException;
import ebhor.model.Student;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class RegisterDAO {

    Connection con = null;
    PreparedStatement ps = null;
    ResultSet rs = null;
    int st;//status

    public int registerStudent(Student student) {
        con = ConnectionFactory.getConnection();
        try {
            String query = "insert into "
                    + "student "
                    + "(name,dob,gender,mailid,mobile_no,password,program,branch,semester) "
                    + "values(?,?,?,?,?,?,?,?,?)";
            ps = con.prepareStatement(query);
            ps.setString(1, student.getName());
            ps.setDate(2, student.getDob());
            ps.setString(3, student.getGender());
            ps.setString(4, student.getMailId());
            ps.setString(5, student.getMobileNo());
            ps.setString(6, student.getEncPassword());
            ps.setString(7, student.getProgram());
            ps.setString(8, student.getBranch());
            ps.setInt(9, student.getSemester());
            st = ps.executeUpdate();
            System.out.println("Inserted  student " + st);
        } catch (MySQLIntegrityConstraintViolationException e) {
            /*This exception is throws when user is already 
            registed with same id, mobileno or mail id*/
            e.printStackTrace();
            st = -1;
        } catch (SQLException e) {
            /*Any SqlException occures then this will execute*/
            e.printStackTrace();
            st = -2;
        }
        return st;
    }
}

package ebhor.dao;

import com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException;

import ebhor.model.Student;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

public class RegisterDAO {

Connection con = null;

PreparedStatement ps = null;

ResultSet rs = null;

int st;//status

public int registerStudent(Student student) {

con = ConnectionFactory.getConnection();

try {

String query = "insert into "

+ "student "

+ "(name,dob,gender,mailid,mobile_no,password,program,branch,semester) "

+ "values(?,?,?,?,?,?,?,?,?)";

ps = con.prepareStatement(query);

ps.setString(1, student.getName());

ps.setDate(2, student.getDob());

ps.setString(3, student.getGender());

ps.setString(4, student.getMailId());

ps.setString(5, student.getMobileNo());

ps.setString(6, student.getEncPassword());

ps.setString(7, student.getProgram());

ps.setString(8, student.getBranch());

ps.setInt(9, student.getSemester());

st = ps.executeUpdate();

System.out.println("Inserted student " + st);

} catch (MySQLIntegrityConstraintViolationException e) {

/*This exception is throws when user is already

registed with same id, mobileno or mail id*/

e.printStackTrace();

st = -1;

} catch (SQLException e) {

/*Any SqlException occures then this will execute*/

e.printStackTrace();

st = -2;

}

return st;

}

RegisterFrame.java

Receiving response from registerStudent().

RegisterDAO dao = new RegisterDAO();
            int st = dao.registerStudent(student);

            System.out.println(st);
            if (st == 1) {
                JOptionPane.showMessageDialog(null, "Registered Successfully");

            }
            if (st == -1) {
                JOptionPane.showMessageDialog(null, "Already Registered");
            }
            if (st == -2) {
                JOptionPane.showMessageDialog(null, "OOps Unable to Register");
            }

RegisterDAO dao = new RegisterDAO();

int st = dao.registerStudent(student);

System.out.println(st);

if (st == 1) {

JOptionPane.showMessageDialog(null, "Registered Successfully");

}

if (st == -1) {

JOptionPane.showMessageDialog(null, "Already Registered");

}

if (st == -2) {

JOptionPane.showMessageDialog(null, "OOps Unable to Register");

}

Finally Saving data on student table

Student Registration Example — Fig: Registration Done

Download Registration Form in Java Swing

RegistrationExample Download

Simple Calculator in Java Applet

Login form in Java Swing and MySql Database with source code

We considered a small example with student details to login From Java Swing and redirecting to another frame after login.

We have covered

Login Page design using JFrame
Validation on Login Page
Event Handling for Login button
Accessing Student details from MySQL database
Matching encrypted password using jBCrypt.

To make our project functionating, we have included additional jar files mysql-connector-java jar file and jBCrypt jar file.

You can check both jar version in below Project Explorer.

Project Explorer for this project is as below.

Project Explorer for Login form in Java Swing — Fig: Project Explorer

In above Figure you can see, there is a package name login and its three sub packages dao, frames and model.

login.dao contains following three files

1. ConnectionFactory.java -Used to establish connection from database.

2. LoginDAO.java– Extracts user details from student table from MySQL database.

3. Student.sql– It is sql query to create table structure. Also contains a record of a student.

login.frame package contains following files

1 LoginFrame.java – It contains JFrame to create login Frame.

2. HomeFrame.java – It contains Jframe to create home Frame.

3. Validation.java – This file is used to validate userid and password field of LoginFrame

login.model this package contains a file

1 Student.java – This file contains necessary fields of students its getter setter and toString() method. This is a simple Pojo File.

Libraries contains jar files

1 jdk1.8 – Using jdk1.8 for this project

2. mysql-connector-java – Used to connect MySQL database with Java

3 JBCrypt – Used to encrypt password.

To Start a new Project in NetBeans click on

File->New Project

From Category select Java and at Projects select Java Application

then click on next

then provide project Name and select Use dedicated folder for Storing libraries then click on Finish.

This will create a project.

Create a package login and inside login create three packages frames, model and dao.

Create a Login Frame

Create a login frame in login.frames package.

General methods in side login frame is as below.

1 Declare component like buttons,textbos, password field etc in side LoginFrame class

2. Create a default constructor inside this create object for declared components.

3. Create a method setBounds() to assing positions for components

4. Add all components to Container in addComponent()

5 Method addActionListener() is created to add actionListeners() to components

6 actionPerformed() overridden method is used to handle the event

7 main() is creating object of class and setting title, visibility, frame size, EXIT_ON_CLOSE and resizable properties of frame.

Following code contains the general structure of frame

package login.frames;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;

public class LoginFrame extends JFrame implements ActionListener {

    /*---------1---------*/
    //declare components(button,label,textbox etc) 
    /*---------2---------*/
    //create objects for components
    public LoginFrame() {
    }

    /*---------3---------*/
    //Place components at specified position
    public void setBounds() {
    }

    /*---------3---------*/
    //Add components to Container
    public void addComponents() {

    }

    /*---------4---------*/
    //Add actionListener to components
    public void addActionListener() {

    }

    /*---------5---------*/
    //Perform actions based on events
    public void actionPerformed(ActionEvent e) {

    }

    public static void main(String[] args) {
        /*Create object of class and set basic properties*/
        LoginFrame frame = new LoginFrame();
        frame.setTitle("Login Form");
        frame.setVisible(true);
        frame.setBounds(250, 250, 370, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);

    }

}

package login.frames;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.JFrame;

public class LoginFrame extends JFrame implements ActionListener {

/*---------1---------*/

//declare components(button,label,textbox etc)

/*---------2---------*/

//create objects for components

public LoginFrame() {

}

/*---------3---------*/

//Place components at specified position

public void setBounds() {

}

/*---------3---------*/

//Add components to Container

public void addComponents() {

}

/*---------4---------*/

//Add actionListener to components

public void addActionListener() {

}

/*---------5---------*/

//Perform actions based on events

public void actionPerformed(ActionEvent e) {

}

public static void main(String[] args) {

/*Create object of class and set basic properties*/

LoginFrame frame = new LoginFrame();

frame.setTitle("Login Form");

frame.setVisible(true);

frame.setBounds(250, 250, 370, 300);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setResizable(false);

}

Add Components to Login Frame

Here components JLabel, JTextField, JButton, Container are declared and its objects are created in default constructor , bounds are assigned in setBounds() and componets are added to container in addComponent().

package login.frames;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class LoginFrame extends JFrame implements ActionListener {

    JLabel userNameLable, passwordLabel;
    JTextField userNameTextField;
    JPasswordField passwordField;
    JButton loginButton;
    Container container;

    public LoginFrame() {
        userNameLable = new JLabel("User Name");
        userNameTextField = new JTextField();
        passwordLabel = new JLabel("Password");
        passwordField = new JPasswordField();
        loginButton = new JButton("Login");
        container = getContentPane();
        container.setLayout(null);
        setBounds();
        addComponents();
        addActionListener();

    }

    public void setBounds() {
        userNameLable.setBounds(10, 10, 100, 30);
        userNameTextField.setBounds(100, 10, 200, 30);
        passwordLabel.setBounds(10, 50, 100, 30);
        passwordField.setBounds(100, 50, 200, 30);
        loginButton.setBounds(100, 100, 200, 30);
    }

    public void addComponents() {
        container.add(userNameLable);
        container.add(userNameTextField);
        container.add(passwordLabel);
        container.add(passwordField);
        container.add(loginButton);
    }

    public void addActionListener() {
    }

    @Override
    public void actionPerformed(ActionEvent e) {

    }

    public static void main(String[] args) {
        LoginFrame frame = new LoginFrame();
        frame.setTitle("Login Form");
        frame.setVisible(true);
        frame.setBounds(250, 250, 370, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);

    }

}

package login.frames;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class LoginFrame extends JFrame implements ActionListener {

JLabel userNameLable, passwordLabel;

JTextField userNameTextField;

JPasswordField passwordField;

JButton loginButton;

Container container;

public LoginFrame() {

userNameLable = new JLabel("User Name");

userNameTextField = new JTextField();

passwordLabel = new JLabel("Password");

passwordField = new JPasswordField();

loginButton = new JButton("Login");

container = getContentPane();

container.setLayout(null);

setBounds();

addComponents();

addActionListener();

}

public void setBounds() {

userNameLable.setBounds(10, 10, 100, 30);

userNameTextField.setBounds(100, 10, 200, 30);

passwordLabel.setBounds(10, 50, 100, 30);

passwordField.setBounds(100, 50, 200, 30);

loginButton.setBounds(100, 100, 200, 30);

}

public void addComponents() {

container.add(userNameLable);

container.add(userNameTextField);

container.add(passwordLabel);

container.add(passwordField);

container.add(loginButton);

}

public void addActionListener() {

}

@Override

public void actionPerformed(ActionEvent e) {

}

public static void main(String[] args) {

LoginFrame frame = new LoginFrame();

frame.setTitle("Login Form");

frame.setVisible(true);

frame.setBounds(250, 250, 370, 300);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setResizable(false);

}

Learn basic JFrame tutorial here

Add Action Listener and perform check for correct userid and password

Added actionListener for loginButton. Action handling is performed in actionPerformed().

We are overriding actionPerformed() of ActionListener Interface.

IF any event occurs then we check its source by e.getSource() method.

Here we are comparing e.getSource() with loginButton. java button click event is handled here.

If login button is clicked then statements inside if statement is executed.

Inside if statment we are getting values of userNameTextField.getText() and passwordField.getText();

getText() is used to get textbox value as text.

getText() of JPassword field is depricated but for demo purpose we are using it.

after getting userid and password we are mathing both with our user id and password

if (userName.equalsIgnoreCase("Test") && password.equalsIgnoreCase("[email protected]"))

if both are matching then print logged in else unable to login.

package login.frames;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class LoginFrame extends JFrame implements ActionListener {

    JLabel userNameLable, passwordLabel;
    JTextField userNameTextField;
    JPasswordField passwordField;
    JButton loginButton;
    Container container;

    public LoginFrame() {
        userNameLable = new JLabel("User Name");
        userNameTextField = new JTextField();
        passwordLabel = new JLabel("Password");
        passwordField = new JPasswordField();
        loginButton = new JButton("Login");
        container = getContentPane();
        container.setLayout(null);
        setBounds();
        addComponents();
        addActionListener();

    }

    public void setBounds() {
        userNameLable.setBounds(10, 10, 100, 30);
        userNameTextField.setBounds(100, 10, 200, 30);
        passwordLabel.setBounds(10, 50, 100, 30);
        passwordField.setBounds(100, 50, 200, 30);
        loginButton.setBounds(100, 100, 200, 30);
    }

    public void addComponents() {
        container.add(userNameLable);
        container.add(userNameTextField);
        container.add(passwordLabel);
        container.add(passwordField);
        container.add(loginButton);
    }

    public void addActionListener() {
        loginButton.addActionListener(this);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println("Event called");
        if (e.getSource() == loginButton) {
            String userName = userNameTextField.getText();
            /*never print password or other sensitive data in console
              this is only for testing purpose*/
            String password = passwordField.getText();
            System.out.println(userName + " " + password);

            //check password provided by user with stored password in database
            if (userName.equalsIgnoreCase("Test") && password.equalsIgnoreCase("1234@.")) {
                System.out.println("Logged in");
            } else {
                System.out.println("Unable to login");
            }
        }
    }

    public static void main(String[] args) {
        LoginFrame frame = new LoginFrame();
        frame.setTitle("Login Form");
        frame.setVisible(true);
        frame.setBounds(250, 250, 370, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);

    }

}

package login.frames;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class LoginFrame extends JFrame implements ActionListener {

JLabel userNameLable, passwordLabel;

JTextField userNameTextField;

JPasswordField passwordField;

JButton loginButton;

Container container;

public LoginFrame() {

userNameLable = new JLabel("User Name");

userNameTextField = new JTextField();

passwordLabel = new JLabel("Password");

passwordField = new JPasswordField();

loginButton = new JButton("Login");

container = getContentPane();

container.setLayout(null);

setBounds();

addComponents();

addActionListener();

}

public void setBounds() {

userNameLable.setBounds(10, 10, 100, 30);

userNameTextField.setBounds(100, 10, 200, 30);

passwordLabel.setBounds(10, 50, 100, 30);

passwordField.setBounds(100, 50, 200, 30);

loginButton.setBounds(100, 100, 200, 30);

}

public void addComponents() {

container.add(userNameLable);

container.add(userNameTextField);

container.add(passwordLabel);

container.add(passwordField);

container.add(loginButton);

}

public void addActionListener() {

loginButton.addActionListener(this);

}

@Override

public void actionPerformed(ActionEvent e) {

System.out.println("Event called");

if (e.getSource() == loginButton) {

String userName = userNameTextField.getText();

/*never print password or other sensitive data in console

this is only for testing purpose*/

String password = passwordField.getText();

System.out.println(userName + " " + password);

//check password provided by user with stored password in database

if (userName.equalsIgnoreCase("Test") && password.equalsIgnoreCase("[email protected]")) {

System.out.println("Logged in");

} else {

System.out.println("Unable to login");

}

public static void main(String[] args) {

LoginFrame frame = new LoginFrame();

frame.setTitle("Login Form");

frame.setVisible(true);

frame.setBounds(250, 250, 370, 300);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setResizable(false);

}

login page in java swing — Fig: Login Page in Java Swing

Fig: Console Result for different userid and password input

Our code is working properly.

Now we will validate user id and password field.

Adding Validation for userid and password

For validation created a class Validation.java in login.frames package.

For validation we are considering following rules

User id and password must not be empty.
User id and password must have minimum 4 characters
User id and password must have maximum 20 characters

Here Done only basic validation. Not validating valid mail id .

Later or you can also use login with mobile number or any other unique id.

According to this rule we have written following validateLogin().

This will accept userid and password and check for above conditions.

validateLogin() returns err ArrayList and that list is displayed in LoginFrame.

package login.frames;
package login.frames;

import java.util.ArrayList;
import java.util.List;

public class Validation {

    public List<String> validateLogin(String uname, String password) {
        ArrayList<String> err = new ArrayList<String>();
        if (uname.isEmpty()) {
            err.add("User Name can not be empty");
        } else if (uname.length() < 4) {
            err.add("User Name is too short");
        } else if (uname.length() > 20) {
            err.add("user Name is too long");
        }
        if (password.isEmpty()) {
            err.add("Password can not be empty");
        } else if (password.length() < 4) {
            err.add("Password is too short");
        } else if (password.length() > 20) {
            err.add("Password is too long");
        }
        return err;
    }
}

package login.frames;

import java.util.ArrayList;

import java.util.List;

public class Validation {

public List<String> validateLogin(String uname, String password) {

ArrayList<String> err = new ArrayList<String>();

if (uname.isEmpty()) {

err.add("User Name can not be empty");

} else if (uname.length() < 4) {

err.add("User Name is too short");

} else if (uname.length() > 20) {

err.add("user Name is too long");

}

if (password.isEmpty()) {

err.add("Password can not be empty");

} else if (password.length() < 4) {

err.add("Password is too short");

} else if (password.length() > 20) {

err.add("Password is too long");

}

return err;

}

Updating LoginFrame to add validation

Here we created object of Validation and called validateLogin().

If any error occurs then errors are displayed with

JOptionPane.showMessageDialog(null, errors.toArray());

@Override
    public void actionPerformed(ActionEvent e) {
        System.out.println("Event called");
        if (e.getSource() == loginButton) {
            String userName = userNameTextField.getText();
            /*never print password or other sensitive data in console
              this is only for testing purpose*/
            String password = passwordField.getText();
            System.out.println(userName + " " + password);

            Validation v = new Validation();
            java.util.List<String> errors = v.validateLogin(userName, password);
            if (errors.size() > 0) {
                JOptionPane.showMessageDialog(null, errors.toArray());
                return;
            }
            //check password provided by user with stored password in database
            if (userName.equalsIgnoreCase("Test") && password.equalsIgnoreCase("1234@.")) {
                System.out.println("Logged in");

            } else {
                System.out.println("User id");

            }
        }
    }

@Override

public void actionPerformed(ActionEvent e) {

System.out.println("Event called");

if (e.getSource() == loginButton) {

String userName = userNameTextField.getText();

/*never print password or other sensitive data in console

this is only for testing purpose*/

String password = passwordField.getText();

System.out.println(userName + " " + password);

Validation v = new Validation();

java.util.List<String> errors = v.validateLogin(userName, password);

if (errors.size() > 0) {

JOptionPane.showMessageDialog(null, errors.toArray());

return;

}

//check password provided by user with stored password in database

if (userName.equalsIgnoreCase("Test") && password.equalsIgnoreCase("[email protected]")) {

System.out.println("Logged in");

} else {

System.out.println("User id");

}

Output for LoginFrame validation is as below

Validation in login form — Fig: Userid and password validation in login form

Checking user id and password from MySQL database

Create MySQL database and table and insert value that is given below

CREATE TABLE student
  (
     id        BIGINT(20) UNSIGNED NOT NULL auto_increment,
     name      VARCHAR(200),
     dob       DATE,
     gender    VARCHAR(10),
     mailid    VARCHAR(100),
     mobile_no VARCHAR(12),
     password  VARCHAR(200),
     program    VARCHAR(100),
     branch    VARCHAR(100),
     semester  INT(2),
     add_date   TIMESTAMP DEFAULT CURRENT_TIMESTAMP(),
     PRIMARY KEY (id),
     UNIQUE KEY (mailid),
     UNIQUE KEY (mobile_no)
  )
engine=innodb
DEFAULT charset=utf8;

CREATE TABLE student

(

id BIGINT(20) UNSIGNED NOT NULL auto_increment,

name VARCHAR(200),

dob DATE,

gender VARCHAR(10),

mailid VARCHAR(100),

mobile_no VARCHAR(12),

password VARCHAR(200),

program VARCHAR(100),

branch VARCHAR(100),

semester INT(2),

add_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP(),

PRIMARY KEY (id),

UNIQUE KEY (mailid),

UNIQUE KEY (mobile_no)

)

engine=innodb

DEFAULT charset=utf8;

Model to Assing JDBC value to Student Object

Student.java is added in login.model

This contains basic fields of students and getter setter and toString().

Object of this class is created in LoginDAO.java to assign value that are extracted from student table.

package login.model;

public class Student {

    long id;
    String name;
    String uname;
    String password;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getUname() {
        return uname;
    }

    public void setUname(String uname) {
        this.uname = uname;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public String toString() {
        return "Student{" + "id=" + id + ", name=" + name + ", uname=" + uname + ", password=" + password + '}';
    }

}

package login.model;

public class Student {

long id;

String name;

String uname;

String password;

public long getId() {

return id;

}

public void setId(long id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getUname() {

return uname;

}

public void setUname(String uname) {

this.uname = uname;

}

public String getPassword() {

return password;

}

public void setPassword(String password) {

this.password = password;

}

@Override

public String toString() {

return "Student{" + "id=" + id + ", name=" + name + ", uname=" + uname + ", password=" + password + '}';

}

Establishing Connection with MySQL Database

ConnectionFactory.java is used to connect MySQL database with username and password and return Connection object.

Following code is how to connect MySQL database with java

package login.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class ConnectionFactory {

    public static Connection getConnection() {
        Connection c = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            c = DriverManager.getConnection("jdbc:mysql://localhost:3306/ebhor?useUnicode=true&characterEncoding=UTF-8", "ebhor_user", "21V6");
        } catch (ClassNotFoundException e) {
            System.out.println("ClassNotFoundException " + e);
        } catch (SQLException e) {
            System.out.println("SQLException " + e);
        }
        return c;
    }
}

package login.dao;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

public class ConnectionFactory {

public static Connection getConnection() {

Connection c = null;

try {

Class.forName("com.mysql.jdbc.Driver");

c = DriverManager.getConnection("jdbc:mysql://localhost:3306/ebhor?useUnicode=true&characterEncoding=UTF-8", "ebhor_user", "21V6");

} catch (ClassNotFoundException e) {

System.out.println("ClassNotFoundException " + e);

} catch (SQLException e) {

System.out.println("SQLException " + e);

}

return c;

}

Accessing Student details from MySQL Database

Following JDBC program (LoginDAO.java) is used to get student details from database.

For this we used PreparedStatement of JDBC.

Here we fetch data from database in java and assigned to student object.

Here we checked user detail with mail id, you can use with mobile number or with both.

package login.dao;

import ebhor.model.Student;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;



public class LoginDAO {

    Connection con = null;
    PreparedStatement ps = null;
    ResultSet rs = null;
    int st;//status

    public Student checkLogin(String uname) {
        Student student = new Student();
        con = ConnectionFactory.getConnection();
        try {
            String query = "select * from student where mailid=?";
            ps = con.prepareStatement(query);
            ps.setString(1, uname);
            rs = ps.executeQuery();
            while (rs.next()) {
                student.setId(rs.getLong("id"));
                student.setName(rs.getString("name"));
                student.setMailId(rs.getString("mailid"));
                student.setPassword(rs.getString("password"));
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                con.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        }
        return student;
    }
}

package login.dao;

import ebhor.model.Student;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

public class LoginDAO {

Connection con = null;

PreparedStatement ps = null;

ResultSet rs = null;

int st;//status

public Student checkLogin(String uname) {

Student student = new Student();

con = ConnectionFactory.getConnection();

try {

String query = "select * from student where mailid=?";

ps = con.prepareStatement(query);

ps.setString(1, uname);

rs = ps.executeQuery();

while (rs.next()) {

student.setId(rs.getLong("id"));

student.setName(rs.getString("name"));

student.setMailId(rs.getString("mailid"));

student.setPassword(rs.getString("password"));

}

} catch (Exception e) {

e.printStackTrace();

} finally {

try {

con.close();

} catch (SQLException ex) {

ex.printStackTrace();

}

return student;

}

Comparing user id and password from DAO in LoginFrame.java

Create object for LoginDAO
call checkLogin(userName) to check whether user exists or not.
If user exists then student.getId() will not be zero.
Compare user password with database stored password using BCrypt.
If userid and password is correct then show HomeFrame
else show appropriate message

Complete Code for HomeFrame.java is

.........
LoginDAO dao = new LoginDAO();
            Student student = dao.checkLogin(userName);
            //Check where student exists in database or not
            System.out.println(student);
            //If Student object is not availabe in database the id=0
            if (student.getId() == 0) {
                System.out.println("No user found with username");
                return;
            }
            //check password provided by user with stored password in database
            if (BCrypt.checkpw(password, student.getPassword())) {
                System.out.println("Logged in");
                new HomeFrame().setVisible(true);
                this.dispose();
            } else {
                System.out.println("Unable to login");
                JOptionPane.showMessageDialog(null, "User id or password is incorrect");
                return;
            }

.........

LoginDAO dao = new LoginDAO();

Student student = dao.checkLogin(userName);

//Check where student exists in database or not

System.out.println(student);

//If Student object is not availabe in database the id=0

if (student.getId() == 0) {

System.out.println("No user found with username");

return;

}

//check password provided by user with stored password in database

if (BCrypt.checkpw(password, student.getPassword())) {

System.out.println("Logged in");

new HomeFrame().setVisible(true);

this.dispose();

} else {

System.out.println("Unable to login");

JOptionPane.showMessageDialog(null, "User id or password is incorrect");

return;

}

Showing HomeFrame after Successful Login

In LoginFrame.java if userid and password is correct then we added setVisible(true) for HomeFrame and dispose() the LoginFrame as below

new HomeFrame().setVisible(true); this.dispose();

HomeFrame.java is create to login.frames this frame is shown after successfully login.

package login.frames;

import java.awt.Container;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class HomeFrame extends JFrame {

    JLabel message;
    Container container = getContentPane();

    public HomeFrame() {
        message = new JLabel("You are successfully logged in");
        container.setLayout(null);
        this.setTitle("Home Form");
        this.setVisible(true);
        this.setBounds(250, 250, 370, 300);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setResizable(false);
        setBounds();
        addComponents();
    }

    public void setBounds() {
        message.setBounds(10, 10, 400, 30);

    }

    public void addComponents() {
        container.add(message);

    }

}

package login.frames;

import java.awt.Container;

import javax.swing.JFrame;

import javax.swing.JLabel;

public class HomeFrame extends JFrame {

JLabel message;

Container container = getContentPane();

public HomeFrame() {

message = new JLabel("You are successfully logged in");

container.setLayout(null);

this.setTitle("Home Form");

this.setVisible(true);

this.setBounds(250, 250, 370, 300);

this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

this.setResizable(false);

setBounds();

addComponents();

}

public void setBounds() {

message.setBounds(10, 10, 400, 30);

}

public void addComponents() {

container.add(message);

}

Java Home Frame after login — Fig: Redirected to home Frame after successful login

AWTProjects Download

Simple Calculator in Java Applet

Registration Form in Java Swing with MySql Database

How to find String length in java with and without string method

Get String length with String length() method

To find String length in java there is a method length().

This method is used to get length of string.

Signature of length method is:

public int length()

1	public int length()

Length method returns the length of the string. it counts the number of unicode in string.

public class MyClass {
    public static void main(String args[]) {
     String text="Hello How are you";
     int length=text.length();
     System.out.println("Length of string "+length);
    
    }
}

public class MyClass {

public static void main(String args[]) {

String text="Hello How are you";

int length=text.length();

System.out.println("Length of string "+length);

}

This is very simple way to get length of a string in java.

Output

Length of string 17

1	Length of string 17

Finding the length of unicode string in java

Here we are considering hindi language stored in String. We use length() to get the string length.

You can take any unicode character to check length string length() works properly.

public class StringLength {
    public static void main(String args[]) {
        String text = "उठो, जागो और तब तक मत रुको जब तक लक्ष्य की प्राप्ति ना हो जाये।";
        int length = text.length();
        System.out.println("Length of string " + length);
    }
}

public class StringLength {

public static void main(String args[]) {

String text = "उठो, जागो और तब तक मत रुको जब तक लक्ष्य की प्राप्ति ना हो जाये।";

int length = text.length();

System.out.println("Length of string " + length);

}

Output

Length of string 63

1	Length of string 63

Finding the String length in java of unicode characters

Here we have stored a unicode value in String and finding its length.

public class StringLength {
    public static void main(String args[]) {
        String text = "\u0041";
        int length = text.length();
        System.out.println("Length of string " + length);
         System.out.println("unicode character is  " + text);
    }
}

public class StringLength {

public static void main(String args[]) {

String text = "\u0041";

int length = text.length();

System.out.println("Length of string " + length);

System.out.println("unicode character is " + text);

}

Output

Length of string 1
unicode character is  A

1 2	Length of string 1 unicode character is A

Using toCharArray() to find String length in java

toCharArray() is another method in String class to convert String to character array.

Signature of toCharArray() is

public char[] toCharArray()

1	public char[] toCharArray()

public class CharArrayLength {
    public static void main(String[] args) {
        String text = "When our false perception is corrected, misery ends also";
        char[] charArray = text.toCharArray();
        int length = charArray.length;
        System.out.println("Length of text is " + length);
    }
}

public class CharArrayLength {

public static void main(String[] args) {

String text = "When our false perception is corrected, misery ends also";

char[] charArray = text.toCharArray();

int length = charArray.length;

System.out.println("Length of text is " + length);

}

In above program String is converted to character array using toCharArray().

Character array is have a field length. This length property finds the length of character array.

Output

Length of text is 56

1	Length of text is 56

Using Function to find the String length in java

In above program you find length of Java String in main method.

Here we have created two static methods length() and length1().

these two methods are accepting string and getting its length.

public class StringLenghtForLoop {
    public static int length(String s) {
        return s.length();
    }
     public static int length1(String s) {
       return s.toCharArray().length;
    }
    public static void main(String[] args) {
        String text = "Hello How are you";
        int length = length(text);
        System.out.println("String length is " + length);
        int length1 = length1(text);
        System.out.println("String length is " + length1);
    }
}

public class StringLenghtForLoop {

public static int length(String s) {

return s.length();

}

public static int length1(String s) {

return s.toCharArray().length;

}

public static void main(String[] args) {

String text = "Hello How are you";

int length = length(text);

System.out.println("String length is " + length);

int length1 = length1(text);

System.out.println("String length is " + length1);

}

Using Recursion to find String length

Here we are using recursion to find the length of string.

When a function is called it is checking the lenth of string if string is empty then return zero else call again itself with adding one to return value.

On each recursive call we are eliminating first character from string.

public class StringLenght {

    public static int length(String s) {
        if (s.isEmpty()) {
            return 0;
        } else {
            return length(s.substring(1))+1;
        }
    }
    public static void main(String[] args) {
        String text = "Hello How are you";
        int length = length(text);
        System.out.println("String length is " + length);
    }
}

public class StringLenght {

public static int length(String s) {

if (s.isEmpty()) {

return 0;

} else {

return length(s.substring(1))+1;

}

public static void main(String[] args) {

String text = "Hello How are you";

int length = length(text);

System.out.println("String length is " + length);

}

Output

String length is 17

1	String length is 17

Hope you learn and understand how to get length of string as we discussed different ways to find string length.

Keep Reading other topics.

Inheritance in Java-Types and Examples

Inheritance in Java is the process of acquiring the properties of one class object into another class object.

It allows the hierarchical classification. Inheritance also provides the facility of reusability.

In Java programming, a class that is inherited is called a superclass or sub class or parent class and class that does the inheriting is called sub class or child class.

If we want to inherit a class, we simply incorporate the definition of one class into another class by using extends keyword.

General form of a class declaration that inherits a super class

class  subClass <strong>extends </strong>  superClass{ 
 <br>
  }

class subClass <strong>extends </strong> superClass{

<br>

}

Type of Inheritance in Java

There are following type of inheritance

Single level Inheritance
Multi-level Inheritance
Hierarchical Inheritance
Hybrid Inheritance

Note: Java does not support multiple inheritance.

Single level Inheritance

Property of single level inheritance is as below

One Super class and one sub class
Sub class inherits the features of super class

Write a program for single level inheritance.

class Parent // create a super class	
{	
    int  x ,y;
    void showA()
    {       
        System.out.println("x="  +x+" y=" + y); 
    }		
   }


class Child extends Parent // create a sub class	
{	
    int  z; 
    void showB()
    {   
        System.out.println("x="  +x + "  y=" + y + " z=" +z );
    }
/* in sub class, member of super class can be accessed directly without any object. */                     }


public class Test {

    public static void main(String arg[]) {
        Child obj = new Child();
        obj.x = 10;	// subclass has access to all public members of its super class	
        obj.y =  20;	// subclass has access to all public members of its super class	
        obj.showA();	// subclass has access to all public members of its super class	
        obj.z = 30;
        obj.showB();
    }
}

class Parent // create a super class

{

int x ,y;

void showA()

{

System.out.println("x=" +x+" y=" + y);

}

class Child extends Parent // create a sub class

{

int z;

void showB()

{

System.out.println("x=" +x + " y=" + y + " z=" +z );

}

/* in sub class, member of super class can be accessed directly without any object. */ }

public class Test {

public static void main(String arg[]) {

Child obj = new Child();

obj.x = 10; // subclass has access to all public members of its super class

obj.y = 20; // subclass has access to all public members of its super class

obj.showA(); // subclass has access to all public members of its super class

obj.z = 30;

obj.showB();

}

Multi level Inheritance

In multi level inheritance inheritance exists in multiple level.

One Super Class
It has a child class
Child class has a child class

This process may continue and each child class inherits feature of all parent class.

program for Multi level inheritance.

class A { 

    int x;

}

class B extends A {

    int y;
}

class C extends B {

    int z;

    void show() {
        System.out.println("x=" + x + "  y=" + y + " z=" + z);
        /* in sub class, member of super class can be accessed directly without any object. */

    }
}

public class Test {

    public static void main(String arg[]) {
        C objC = new C();
        objC.x = 10;	// subclass has access to all public members of its super class
        objC.y = 20;	// subclass has access to all public members of its super class
        objC.z = 30;
        objC.show();	// subclass has access to all public members of its super class	
    }
}

class A {

int x;

}

class B extends A {

int y;

}

class C extends B {

int z;

void show() {

System.out.println("x=" + x + " y=" + y + " z=" + z);

/* in sub class, member of super class can be accessed directly without any object. */

}

public class Test {

public static void main(String arg[]) {

C objC = new C();

objC.x = 10; // subclass has access to all public members of its super class

objC.y = 20; // subclass has access to all public members of its super class

objC.z = 30;

objC.show(); // subclass has access to all public members of its super class

}

Result

x=10  y=20 z=30

1	x=10 y=20 z=30

Hierarchical Inheritance

Hybrid Inheritance

<strong></strong>

1	<strong></strong>

Result

x=10 y=20
x=10  y=20 z=30

1 2	x=10 y=20 x=10 y=20 z=30

Note: A subclass can access the public member of super class. A subclass can’t access the private member of super class.

Super Class Cant Access Sub Class Member

A sub class can access all the public member of super class but reverse is not true. Super class cannot access sub class data.

class Parent // create a super class	
{

    int x;

    void showParent() {
        System.out.println("x =" + x + "  y=" + y);
        /* error, y cant be accessed here, because y is a member of sub class. */
    }
}

class Child extends Parent // create a sub class
{

    int y;

    void showChild() {
         System.out.println("x =" + x + "  y=" + y);
    }
    /* in sub class, member of super class can be accessed directly without any object. */
}

public class TestInheritance {

    public static void main(String arg[]) {
        Child obj = new Child();
        obj.x = 10;	// subclass has access to all public members of its super class	
        obj.y = 20;	// subclass has access to all public members of its super class
        obj.showParent();	// subclass has access to all public members of its super class	
        obj.showChild();
    }
}

class Parent // create a super class

{

int x;

void showParent() {

System.out.println("x =" + x + " y=" + y);

/* error, y cant be accessed here, because y is a member of sub class. */

}

class Child extends Parent // create a sub class

{

int y;

void showChild() {

System.out.println("x =" + x + " y=" + y);

}

/* in sub class, member of super class can be accessed directly without any object. */

}

public class TestInheritance {

public static void main(String arg[]) {

Child obj = new Child();

obj.x = 10; // subclass has access to all public members of its super class

obj.y = 20; // subclass has access to all public members of its super class

obj.showParent(); // subclass has access to all public members of its super class

obj.showChild();

}

Result

error: cannot find symbol
        System.out.println("x =" + x + "  y=" + y);
                                                ^
  symbol:   variable y
  location: class Parent
1 error

error: cannot find symbol

System.out.println("x =" + x + " y=" + y);

symbol: variable y

location: class Parent

1 error

A sub class can’t access the private member of super class.

class A { // super class	

    private int x;
}

class B extends A {// sub class	

    int y;

    void showB() {
        System.out.println("x & y =" + x + "    " + y); //error 
        /*  sub class, can’t access private member its super class . */
    }

}

public class Test11 {

    public static void main(String args9[]) {
        B objB = new B();
        objB.showB();

    }
}

class A { // super class

private int x;

}

class B extends A {// sub class

int y;

void showB() {

System.out.println("x & y =" + x + " " + y); //error

/* sub class, can’t access private member its super class . */

}

public class Test11 {

public static void main(String args9[]) {

B objB = new B();

objB.showB();

}

Result

Test11.java:11: error: x has private access in A
        System.out.println("x=" + x + "   y=" + y); //error 
                                       ^
1 error

Test11.java:11: error: x has private access in A

System.out.println("x=" + x + " y=" + y); //error

1 error

Write a program for Hierarchical Inheritance.

class A {

    int x;
}

class B extends A {

    int y;

    void showB() {
        System.out.println("x=" + x + "  y=" + y);
        /* in sub class, member of super class can be accessed directly without any object. */
    }
}

class C extends A {

    int z;

    void showC() {
        System.out.println("x=" + x + "  z=" + z);
        /* in sub class, member of super class can be accessed directly without any object. */
    }
}

public class Test {

    public static void main(String arg[]) {
        B objB = new B();
        C objC = new C();
        objB.x = 10;	// subclass has access to all public members of its super class	
        objB.y = 20;	// subclass has access to all public members of its super class				
        objC.x = 100;	// subclass has access to all public members of its super class		
        objC.z = 200;	// subclass has access to all public members of its super class				
        objB.showB();	// subclass has access to all public members of its super class
        objC.showC();	// subclass has access to all public members of its super class	
    }
}

class A {

int x;

}

class B extends A {

int y;

void showB() {

System.out.println("x=" + x + " y=" + y);

/* in sub class, member of super class can be accessed directly without any object. */

}

class C extends A {

int z;

void showC() {

System.out.println("x=" + x + " z=" + z);

/* in sub class, member of super class can be accessed directly without any object. */

}

public class Test {

public static void main(String arg[]) {

B objB = new B();

C objC = new C();

objB.x = 10; // subclass has access to all public members of its super class

objB.y = 20; // subclass has access to all public members of its super class

objC.x = 100; // subclass has access to all public members of its super class

objC.z = 200; // subclass has access to all public members of its super class

objB.showB(); // subclass has access to all public members of its super class

objC.showC(); // subclass has access to all public members of its super class

}

Result

x=10  y=20
x=100  z=200

1 2	x=10 y=20 x=100 z=200

String in Java- Constructor methods and examples

Java String is defined in java.lang.String.

Java String is a sequence of characters quoted in double quote (” “).

Java String Constructors

Sr No	Constructor and description
1	String() Create a new empty string object
2	String(byte[] bytes) Construct a string object with byte array
3	String(char[] value) Construct a string object with character array
4	String(String original) Create a string with another string
5	String(StringBuffer buffer) Create a string with StringBuffer object
6	String(StringBuilder builder) Create a string with StringBuilder object

Java String Methods

There are many methods avaible in string class few common and widely used methods are

Java String Method charAt()

This method takes one integer argument and return a character specified at index position.

For any string the index value starts from 0 to string length -1 position.

If passed index value not in valid range then it throws IndexOutOfBoundsException.

For example string Hello Friends contains 13 characters starting from 0 to 12 H is first position with index value 0, F is in seventh position with index value 6 and s is in 13 position with index value 12.

Using number other then 0 to 12( 0 to length()-1) will result in IndexOutOfBountException

Signature:

public char charAt(int index)

Parameters:

index -Integer index value to get character at specified index position.

Return:

Character at passed index value.

Exception Throws:

IndexOutOfBoundsException If index value in not between 0 to String length()-1

Example

public class StringChatAtExample {

    public static void main(String args[]) {
        String test = "Java String charAt() example";
        char firstCharacter = test.charAt(0);
        char sixthCharacter = test.charAt(5);
        char lastCharacter = test.charAt(test.length() - 1);
        System.out.println("String:" + test);
        System.out.println("Character at first position: " + firstCharacter);
        System.out.println("Character at sixth position: " + sixthCharacter);
        System.out.println("Character at last position: " + lastCharacter);
    }

}

public class StringChatAtExample {

public static void main(String args[]) {

String test = "Java String charAt() example";

char firstCharacter = test.charAt(0);

char sixthCharacter = test.charAt(5);

char lastCharacter = test.charAt(test.length() - 1);

System.out.println("String:" + test);

System.out.println("Character at first position: " + firstCharacter);

System.out.println("Character at sixth position: " + sixthCharacter);

System.out.println("Character at last position: " + lastCharacter);

}

Result

String:Java String charAt() example
Character at first position: J
Character at sixth position: S
Character at last position: e

String:Java String charAt() example

Character at first position: J

Character at sixth position: S

Character at last position: e

Now Print all characters with its index value

Example

public class StringChatAtExample1 {
    public static void main(String args[]) {
        String test = "Java String charAt() example";
       for(int i=0;i&lt;=test.length()-1;i++){
           System.out.println("Character at  index value "+i+" = "+test.charAt(i));
       }
    }

}

public class StringChatAtExample1 {

public static void main(String args[]) {

String test = "Java String charAt() example";

for(int i=0;i<=test.length()-1;i++){

System.out.println("Character at index value "+i+" = "+test.charAt(i));

}

Result

Character at  index value 0 = J
Character at  index value 1 = a
Character at  index value 2 = v
Character at  index value 3 = a
Character at  index value 4 =  
Character at  index value 5 = S
Character at  index value 6 = t
Character at  index value 7 = r
Character at  index value 8 = i
Character at  index value 9 = n
Character at  index value 10 = g
Character at  index value 11 =  
Character at  index value 12 = c
Character at  index value 13 = h
Character at  index value 14 = a
Character at  index value 15 = r
Character at  index value 16 = A
Character at  index value 17 = t
Character at  index value 18 = (
Character at  index value 19 = )
Character at  index value 20 =  
Character at  index value 21 = e
Character at  index value 22 = x
Character at  index value 23 = a
Character at  index value 24 = m
Character at  index value 25 = p
Character at  index value 26 = l
Character at  index value 27 = e

1 Create Table in MySQL Database

2. SetUp Pagination Project

3 Create a Model to hold Data

4 Create a DAO Class to Perform JDBC Operations

5 Create Frame to show data in JPanel

6 Implement Pagination Concepts

Steps to develop Registration Form in Java Swing is as below

1 Create User Interface using JFrame

A. Create a basic structure for frame

2 Collect all data in Model sent from UI

3 Validate and Process Received data

Processing Data

4 Saving data to MySql Database

Read More

Create a Login Frame

Add Components to Login Frame

Add Action Listener and perform check for correct userid and password

Adding Validation for userid and password

Checking user id and password from MySQL database

Model to Assing JDBC value to Student Object

Establishing Connection with MySQL Database

Accessing Student details from MySQL Database

Showing HomeFrame after Successful Login

Get String length with String length() method

Finding the length of unicode string in java

Finding the String length in java of unicode characters

Using toCharArray() to find String length in java

Using Function to find the String length in java

Using Recursion to find String length

General form of a class declaration that inherits a super class

Type of Inheritance in Java

Single level Inheritance

Multi level Inheritance

Hierarchical Inheritance

Hybrid Inheritance

Super Class Cant Access Sub Class Member

A sub class can’t access the private member of super class.

Java String Constructors

Java String Methods

Java String Method charAt()

Signature:

Parameters:

Return:

Exception Throws:

Example

Result

Example

Result