Java program to print vowels in a String

In Java, String is represented as an Object.

String characters are represented in Unicode encoding.

In the English language, there are five vowels a, e, i, o, and u.

In any string, vowels can be in small or in large letters.

Here using the Java program we will see how to find vowels in the given string.

if (s.charAt(i) == ‘a’ || s.charAt(i) == ‘e’ || s.charAt(i) == ‘i’ || s.charAt(i) == ‘o’ || s.charAt(i) == ‘u’ || s.charAt(i) == ‘A’ || s.charAt(i) == ‘E’ || s.charAt(i) == ‘I’ || s.charAt(i) == ‘O’ || s.charAt(i) == ‘U’) {
System.out.println(“Found vowel ” + s.charAt(i) + ” at position ” + i);
}

Vowels program in java

Vowel program in java are discussed as follows

We created many programs to check and count vowels and consonants from String, StringBuffer, and from files.

Java program to print vowels in a String is as below

Java program to print vowels in a String

Steps to develop the program

Take a String
Create a loop to iterate each character of the string
Inside loop check characters for vowel, both for upper and lower case
If the character is a vowel then print its position and character

public class VowelChecker {
    public static void main(String[] args) {
        String s = "Hello how are you WhAt is this";
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'a' || s.charAt(i) == 'e' || s.charAt(i) == 'i' || s.charAt(i) == 'o' || s.charAt(i) == 'u'
                    || s.charAt(i) == 'A' || s.charAt(i) == 'E' || s.charAt(i) == 'I' || s.charAt(i) == 'O' || s.charAt(i) == 'U') {
                System.out.println("Found vowel " + s.charAt(i) + " at position " + i);
            }
        }
    }
}

public class VowelChecker {

public static void main(String[] args) {

String s = "Hello how are you WhAt is this";

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

if (s.charAt(i) == 'a' || s.charAt(i) == 'e' || s.charAt(i) == 'i' || s.charAt(i) == 'o' || s.charAt(i) == 'u'

|| s.charAt(i) == 'A' || s.charAt(i) == 'E' || s.charAt(i) == 'I' || s.charAt(i) == 'O' || s.charAt(i) == 'U') {

System.out.println("Found vowel " + s.charAt(i) + " at position " + i);

}

In the above program, we created for loop and it runs up to string length.

charAt() is used to access characters at specified index position.

Found vowel e at position 1
Found vowel o at position 4
Found vowel o at position 7
Found vowel a at position 10
Found vowel e at position 12
Found vowel o at position 15
Found vowel u at position 16
Found vowel A at position 20
Found vowel i at position 23
Found vowel i at position 28

Found vowel e at position 1

Found vowel o at position 4

Found vowel o at position 7

Found vowel a at position 10

Found vowel e at position 12

Found vowel o at position 15

Found vowel u at position 16

Found vowel A at position 20

Found vowel i at position 23

Found vowel i at position 28

The above program is simple we can make some improvements to it.

We are comparing both uppercase and lower case, we can convert complete string in lower case and compare it will reduce all uppercase comparison.

How to find vowels in a string in java

write a java program to display all the vowels from a given string.

public class VowelChecker {
    public static void main(String[] args) {
        String s = "Hello how are you WhAt is this";
        String temp = s.toLowerCase();
        for (int i = 0; i < temp.length(); i++) {
            if (temp.charAt(i) == 'a' || temp.charAt(i) == 'e' || temp.charAt(i) == 'i' || temp.charAt(i) == 'o' || temp.charAt(i) == 'u') {
                System.out.println("Found vowel " + temp.charAt(i) + " at position " + i);
            }
        }
    }
}

public class VowelChecker {

public static void main(String[] args) {

String s = "Hello how are you WhAt is this";

String temp = s.toLowerCase();

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

if (temp.charAt(i) == 'a' || temp.charAt(i) == 'e' || temp.charAt(i) == 'i' || temp.charAt(i) == 'o' || temp.charAt(i) == 'u') {

System.out.println("Found vowel " + temp.charAt(i) + " at position " + i);

}

Output

Found vowel e at position 1
Found vowel o at position 4
Found vowel o at position 7
Found vowel a at position 10
Found vowel e at position 12
Found vowel o at position 15
Found vowel u at position 16
Found vowel a at position 20
Found vowel i at position 23
Found vowel i at position 28

Found vowel e at position 1

Found vowel o at position 4

Found vowel o at position 7

Found vowel a at position 10

Found vowel e at position 12

Found vowel o at position 15

Found vowel u at position 16

Found vowel a at position 20

Found vowel i at position 23

Found vowel i at position 28

count vowels in a string java Read from File

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
public class VovelCounter {
    public static void main(String[] args) {
        Scanner sc = null;
        int count = 0;
        StringBuffer sb = new StringBuffer();
        try {
            File file = new File("D://test.txt");
            sc = new Scanner(file);
        } catch (FileNotFoundException ex) {
            System.out.println("File Not Found " + ex);
        }
        while (sc.hasNextLine()) {
            sb.append(sc.nextLine());
            sb.append(System.lineSeparator());
        }
        String s1 = sb.toString().toLowerCase();
        for (int i = 0; i < s1.length(); i++) {
            if (s1.charAt(i) == 'a' || s1.charAt(i) == 'e' || s1.charAt(i) == 'i' || s1.charAt(i) == 'o' || s1.charAt(i) == 'u') {
                System.out.print(" "+s1.charAt(i));
                count++;
            }
        }
        System.out.println("");
        System.out.println("Vowel Count " + count);
    }
}

import java.io.File;

import java.io.FileNotFoundException;

import java.util.Scanner;

public class VovelCounter {

public static void main(String[] args) {

Scanner sc = null;

int count = 0;

StringBuffer sb = new StringBuffer();

try {

File file = new File("D://test.txt");

sc = new Scanner(file);

} catch (FileNotFoundException ex) {

System.out.println("File Not Found " + ex);

}

while (sc.hasNextLine()) {

sb.append(sc.nextLine());

sb.append(System.lineSeparator());

}

String s1 = sb.toString().toLowerCase();

for (int i = 0; i < s1.length(); i++) {

if (s1.charAt(i) == 'a' || s1.charAt(i) == 'e' || s1.charAt(i) == 'i' || s1.charAt(i) == 'o' || s1.charAt(i) == 'u') {

System.out.print(" "+s1.charAt(i));

count++;

}

System.out.println("");

System.out.println("Vowel Count " + count);

}

test.txt file is stored in d drive and file content is as below.

The Scanner class is used to read test.txt file.

Java is a Object Oriented Programming Language
Java is Simple
Java is Secure
Java is Robust
Java is Multithreaded
Java is Distributed

Java is a Object Oriented Programming Language

Java is Simple

Java is Secure

Java is Robust

Java is Multithreaded

Java is Distributed

a a i a o e o i e e o a i a u a e a a i i e a a i e u e a a i o u a a i u i e a e a a i i i u e
Vowel Count 48

1 2	a a i a o e o i e e o a i a u a e a a i i e a a i e u e a a i o u a a i u i e a e a a i i i u e Vowel Count 48

Vowels program in java using switch case

import java.util.Scanner;
public class VowelChecker1 {
    public static void main(String[] args) {
        System.out.println("Enter a character:");
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        char c = s.charAt(0);
        boolean isAlpha = Character.isAlphabetic(c);
        if (!isAlpha) {
            System.out.println("Enter a Alphabet");
            System.exit(0);
        }

        switch (c) {
            case 'a':
            case 'e':
            case 'i':
            case 'o':
            case 'u':
            case 'A':
            case 'E':
            case 'I':
            case 'O':
            case 'U':
                System.out.println("You Entered Vowel " + c);
                break;
            default:
                System.out.println("You Entered consonant " + c);
        }
    }
}

import java.util.Scanner;

public class VowelChecker1 {

public static void main(String[] args) {

System.out.println("Enter a character:");

Scanner sc = new Scanner(System.in);

String s = sc.next();

char c = s.charAt(0);

boolean isAlpha = Character.isAlphabetic(c);

if (!isAlpha) {

System.out.println("Enter a Alphabet");

System.exit(0);

}

switch (c) {

case 'a':

case 'e':

case 'i':

case 'o':

case 'u':

case 'A':

case 'E':

case 'I':

case 'O':

case 'U':

System.out.println("You Entered Vowel " + c);

break;

default:

System.out.println("You Entered consonant " + c);

}

Q: write a program to determine whether the input character is a vowel or consonant or not an alphabet

program to count the number of vowels and consonants in a given string in java

import java.util.Scanner;

public class VowelClass2 {

    public static void main(String[] args) {
        System.out.println("Enter a character:");
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        char[] vowels = {'a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U'};
        char c = s.charAt(0);
        boolean found = false;
        boolean isAlpha = Character.isAlphabetic(c);
        if (!isAlpha) {
            System.out.println("Enter a Alphabet Character");
            System.exit(0);
        }

        for (char ch : vowels) {
            if (ch == c) {
                found = true;
                break;
            }

        }
        if (found) {
            System.out.println("Character is Vowel");
        } else {
            System.out.println("Character is Consonant ");
        }
    }

}

import java.util.Scanner;

public class VowelClass2 {

public static void main(String[] args) {

System.out.println("Enter a character:");

Scanner sc = new Scanner(System.in);

String s = sc.next();

char[] vowels = {'a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U'};

char c = s.charAt(0);

boolean found = false;

boolean isAlpha = Character.isAlphabetic(c);

if (!isAlpha) {

System.out.println("Enter a Alphabet Character");

System.exit(0);

}

for (char ch : vowels) {

if (ch == c) {

found = true;

break;

}

if (found) {

System.out.println("Character is Vowel");

} else {

System.out.println("Character is Consonant ");

}

Character class contains method isAlphabetic.

This method is checking whether a number is an alphabet or not.

If the number is alphabet then match the character using for each loop with vowel characters stored in the array.

If matched then the character is vowel else consonant.

Java program to replace vowels in a string

import java.util.Scanner;

public class VovelClass3 {

    public static void main(String[] args) {
        System.out.println("Enter a character:");
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        String newString = s.replaceAll("[aeiouAEIOU]", "@");
        System.out.println("Your String is " + s);
        System.out.println("New String is " + newString);
    }
}

import java.util.Scanner;

public class VovelClass3 {

public static void main(String[] args) {

System.out.println("Enter a character:");

Scanner sc = new Scanner(System.in);

String s = sc.nextLine();

String newString = s.replaceAll("[aeiouAEIOU]", "@");

System.out.println("Your String is " + s);

System.out.println("New String is " + newString);

}

Enter a character:
Hello How are You
Your String is Hello How are You
New String is H@ll@ H@w @r@ Y@@

Enter a character:

Hello How are You

Your String is Hello How are You

New String is H@ll@ H@w @r@ Y@@

How do you print the number of vowels and consonants in a string?

package com.atom.basic;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
public class VowelnConsonantCount {
	public static void countVowelnCons(StringBuffer s) {
		int vowelCount = 0;
		int consonantCount = 0;
		for (int i = 0; i < s.length(); i++) {
			if (s.charAt(i) == 'a' || s.charAt(i) == 'e' || s.charAt(i) == 'i' || s.charAt(i) == 'o'
					|| s.charAt(i) == 'u' || s.charAt(i) == 'A' || s.charAt(i) == 'E' || s.charAt(i) == 'I'
					|| s.charAt(i) == 'O' || s.charAt(i) == 'U') {
				vowelCount++;
			} else if (s.charAt(i) >= 'a' && s.charAt(i) <= 'z' || s.charAt(i) >= 'A' && s.charAt(i) <= 'Z') {
				consonantCount++;
			}
		}
		System.out.println("Total Vowels are " + vowelCount);
		System.out.println("Total Consonant are " + consonantCount);
	}
	public static void main(String args[]) {
		try {
			Scanner sc = new Scanner(new File("D:\\file.txt"));
			StringBuffer sb = new StringBuffer();
			while (sc.hasNext()) {
				sb.append(sc.nextLine());
			}
			countVowelnCons(sb);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

package com.atom.basic;

import java.io.File;

import java.io.FileNotFoundException;

import java.util.Scanner;

public class VowelnConsonantCount {

public static void countVowelnCons(StringBuffer s) {

int vowelCount = 0;

int consonantCount = 0;

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

if (s.charAt(i) == 'a' || s.charAt(i) == 'e' || s.charAt(i) == 'i' || s.charAt(i) == 'o'

|| s.charAt(i) == 'u' || s.charAt(i) == 'A' || s.charAt(i) == 'E' || s.charAt(i) == 'I'

|| s.charAt(i) == 'O' || s.charAt(i) == 'U') {

vowelCount++;

} else if (s.charAt(i) >= 'a' && s.charAt(i) <= 'z' || s.charAt(i) >= 'A' && s.charAt(i) <= 'Z') {

consonantCount++;

}

System.out.println("Total Vowels are " + vowelCount);

System.out.println("Total Consonant are " + consonantCount);

}

public static void main(String args[]) {

try {

Scanner sc = new Scanner(new File("D:\\file.txt"));

StringBuffer sb = new StringBuffer();

while (sc.hasNext()) {

sb.append(sc.nextLine());

}

countVowelnCons(sb);

} catch (FileNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

Total Vowels are 111
Total Consonant are 224

1 2	Total Vowels are 111 Total Consonant are 224

Java program to print vowels in a String

Vowels program in java

Java program to print vowels in a String

How to find vowels in a string in java

write a java program to display all the vowels from a given string.

count vowels in a string java Read from File

Vowels program in java using switch case

Q: write a program to determine whether the input character is a vowel or consonant or not an alphabet

program to count the number of vowels and consonants in a given string in java

Java program to replace vowels in a string

How do you print the number of vowels and consonants in a string?

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