Primitive Data Types in Java

Primitive data types are primary and basic data types in java.

In Java there are 8 primitive data types.

List of primitive datatypes in java is as follows

byte
short
int
long
float
double
char
boolean

Details of all data types are below.

1 Java Integer Data Type

There are four integer data types (byte, short, int and long) in java that can hold integer values.

All four data types with default value size and minimum and maximum value range that can store are shown below

Type	Size	Min Max Value
byte	8 bits	-2⁷, 2⁷ -1
short	16 bits	-2¹⁵, 2¹⁵ -1
int	32 bits	-2³¹, 2³¹ -1
long	64 bits	-2⁶³, 2⁶³ -1

A byte data type in Java

Byte stores 8 bits signed integer value.
byte stores data in range of -128 to 127.
Default value of byte is 0.
Byte data type can use where we have to save memory during data storage.

B short Data type in java

short stores 16 bits signed integer value.
short stores data in range of -32768 to 32767.
Default value of short is 0.
Short data type can use where we have to save memory during data storage.

C int Data type in java

int stores 32 bits signed and unsigned integer value.
int stores data in range of -2^31 to -2^31-1 for signed integer and 0 to 2^32-1 for unsigned integer.
Default value of short is 0.
Int data type can used to represent normal integer values.

D long Data type in java

long stores 64 bits signed and unsigned long integer value.
long stores data in range of -2^63 to -2^63-1 for signed integer and 0 to 2^64-1 for unsigned integer.
Default value of short is 0.
long data type can used to represent higher integer values.

Lets see a simple program to initialize and print integer data type in java.

class DemoInteger {

    public static void main(String args[]) {
        byte b;
        short x, y;
        int i, j, k;
        long l;
        b = 120;
        x = 200;
        y = 300;
        i = 20;
        j = 500;
        k = i * j;
        l = 30000;
        System.out.println("value of byte b = " + b);
        System.out.println("value of short x and y = " + x + " " + y);
        System.out.println("value of int i, j and k = " + i + " " + j + " " + k);
        System.out.println("value of long l = " + l);
    }
}

class DemoInteger {

public static void main(String args[]) {

byte b;

short x, y;

int i, j, k;

long l;

b = 120;

x = 200;

y = 300;

i = 20;

j = 500;

k = i * j;

l = 30000;

System.out.println("value of byte b = " + b);

System.out.println("value of short x and y = " + x + " " + y);

System.out.println("value of int i, j and k = " + i + " " + j + " " + k);

System.out.println("value of long l = " + l);

}

Output

value of byte b = 120
value of short x and y = 200 300
value of int i, j and k = 20 500 10000
value of long l = 30000

value of byte b = 120

value of short x and y = 200 300

value of int i, j and k = 20 500 10000

value of long l = 30000

2 Float and Double Data Types

Floating point value (example 11.23, 333.3330 etc. ) can be stored in data type float and double.

Small floating value can be stored in float and large floating stored in double.

java data types float and double contains real values.

Type	Default	Size
float	0.0	32 bits
double	0.0	64 bits

A float data type in java

float stores decimal values in 32 bits, represents data in single-precision IEEE754 floating point.
floats stores fractional values in range of 3.4e-038 to 3.4e+038.
Default value of float is 0.0.
float data type can used to represent fractional values.

B double data type in java

double stores decimal values in 64 bits, represents data in double-precision IEEE754 floating point.
double stores fractional values in range of 1.7e-308 to 1.7e+308.
Default value of double is 0.0.
double data type can used to represent fractional values with more precision.

Write a program to demonstrate use of float data types.

<pre brush="java">
public class DemoFloat {

    public static void main(String args[]) {
        float f;
        double x, y;
        f = 11.23f;
        x = 200.2222;
        y = 100.1111;
        double z = x - y;
        System.out.println("value of float data f = " + f);
        System.out.println("value of double data  x= " + x);
        System.out.println("value of double data  y= " + y);
        System.out.println("value of double data  z= " + z);
    }

}

public class DemoFloat {

public static void main(String args[]) {

float f;

double x, y;

f = 11.23f;

x = 200.2222;

y = 100.1111;

double z = x - y;

System.out.println("value of float data f = " + f);

System.out.println("value of double data x= " + x);

System.out.println("value of double data y= " + y);

System.out.println("value of double data z= " + z);

}

Output

value of float data f = 11.23
value of double data  x= 200.2222
value of double data  y= 100.1111
value of double data  z= 100.1111

value of float data f = 11.23

value of double data x= 200.2222

value of double data y= 100.1111

value of double data z= 100.1111

3 Java Character Data Type

Character data ( example ‘a’ , ‘b’ , ‘f’, ….. etc. ) is stored in “char” data type.

Type	Default	Size
char	\u0000	16 bits

B char data type in java

char stores single 16 bit unicode character
double stores fractional values in range of 1.7e-308 to 1.7e+308.
Default value of double is 0.0.
double data type can used to represent fractional values with more precision.

Write a program to demonstrate char data types.

public class DemoChar {

    public static void main(String args[]) {
        char c;
        c = 'a';
        System.out.println("value of char data c = " + c);
    }
}

public class DemoChar {

public static void main(String args[]) {

char c;

c = 'a';

System.out.println("value of char data c = " + c);

}

Result

value of chart data c =  a

1	value of chart data c = a

Program to print character using ASCII value

public class DemoChar1 {

    public static void main(String args[]) {
        char c, d;
        c = 'a';
        d = 65;  // ASCII value of A is 65
        System.out.println("value of char data c and d = " + c + " " + d);
    }
}

public class DemoChar1 {

public static void main(String args[]) {

char c, d;

c = 'a';

d = 65; // ASCII value of A is 65

System.out.println("value of char data c and d = " + c + " " + d);

}

Result

value of chart data c and d =a A

1	value of chart data c and d =a A

4 Java Boolean Data Type

boolean data type in java store the true and false value.

By default value of boolean data type is false.

Type	Default	Size
boolean	false	1 bit

Write a program to demonstrate boolean data types.

public class DemoBoolean {

    public static void main(String args[]) {
        Boolean b = true;
        if (b) {
            System.out.println("A");
        } else {
            System.out.println("B");
        }
        System.out.println("value of 10>9  = " + (10 > 9));
    }
}

public class DemoBoolean {

public static void main(String args[]) {

Boolean b = true;

if (b) {

System.out.println("A");

} else {

System.out.println("B");

}

System.out.println("value of 10>9 = " + (10 > 9));

}

Result

A
value of 10&gt;9  = true

1 2	A value of 10>9 = true