Data Type In Java

There are two data types in JAVA. Lets take a graphical representation to understand it.
Data Type In Java

Lets take graphical representation to understand the primitive data type memory required , value holding capacity range and their default value.

Primitive data type memory, range and their default value

Lets take a example to understand the primitive data type:

1) boolean primitive data type example:

package primitiveDataType;

/**
 * 
 * boolean is a primitive data type and it takes 1 bits of memory
 * Its default value is false
 */
public class BooleanPrimitiveDataType {

	public static void main(String[] args) {
	boolean booleanVariable=true;
	System.out.println("Boolean value is : "+booleanVariable);
	}
}

2) byte primitive data type example:

package primitiveDataType;

/**
 * 
 * byte is a primitive data type and takes 8 bits(1 byte) of memory
 * Its value-range lies between -128 to 127 (inclusive)
 * Its minimum value is -128 and maximum value is 127
 * Its default value is 0 
 *
 */
public class BytePrimitiveDataType {

 public static void main(String[] args) {
	byte byteVariable=127;
	System.out.println(byteVariable);
	byteVariable='p';
	System.out.println((char)byteVariable);
 }
}

3) char primitive data type example:
package primitiveDataType;

/**
 * 
 * short is a primitive data type and takes 16 bits(2 byte) of memory
 * Its value range lies between 
 * '\u0000' (or 0) to '\uffff' (or 65,535 inclusive)
 * Its default value is '\u0000' 
 *
 */
public class CharPrimitiveDataType {

 public static void main(String[] args) {
	char name='p';
	System.out.println(name);
 }
}

4) short primitive data type example:

package primitiveDataType;

/**
 * 
 * short is a primitive data type and takes 16 bits(2 byte) of memory
 * Its value-range lies between -32,768 to 32,767 (inclusive).
 * Its minimum value is -32,768 and maximum value is 32,767. Its default value is 0. 
 *
 */
public class ShortPrimitiveDataType {

 public static void main(String[] args) {
	//It will accept only max value 32767
	short shortVariable=32767;
	System.out.println(shortVariable);
	shortVariable=-32768;
	System.out.println(shortVariable);
		
 }
}

5) int primitive data type example:

package primitiveDataType;

/**
 * 
 * short is a primitive data type and takes 32 bits(4 byte) of memory
 * Its value range lies between - 2,147,483,648  
 * to 2,147,483,647  (inclusive)
 * Its minimum value is -32,768 and maximum value is 32,767
 * Its default value is 0
 *
 */
public class IntPrimitiveDataType {

 public static void main(String[] args) {
 /**
  * It will accept only max value 2,147,483,647, 
  * if you will try to put above the mentioned range
  * it will throw error
  */
 int intVariable=2147483647;
 System.out.println("Max acceptable value is "+intVariable);
 intVariable=-2147483648;
 System.out.println("Min acceptable value is :"+intVariable);
		
 }
}

6) long  primitive data type example:

package primitiveDataType;

/**
 * 
 * short is a primitive data type and takes 64 bits(8 byte) of memory
 * Its value range lies between
 * -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807(inclusive)
 * Its minimum value is -9,223,372,036,854,
 * 775,808 and maximum value is 9,223,372,036,854,775,807
 * Its default value is 0L 
 *
 */
public class LongPrimitiveDataType {

 public static void main(String[] args) {
/**
 * It will accept only max value 9,223,372,036,854,775,807, 
 * if you will try to put above the mentioned 
 * range it will throw error
 * All literal  numbers in java are by default ints,
 * which has range -2147483648 to 2147483647 inclusive.
 * Your literals are outside this range, 
 * so to  make this compile you need to indicate they're
 * long literals (ie suffix with L):
 * You must use L to say to the compiler that it is a long literal.
 */
 long longVariable=9223372036854775807L;
 System.out.println("Max acceptable value is "+longVariable);
 longVariable=-9223372036854775808L;
 System.out.println("Min acceptable value is :"+longVariable);
		
 }
}

7) float  primitive data type example:

package primitiveDataType;

/**
 * 
 * float is a primitive data type and takes 32 bits(4 byte) of memory
 * The smallest decimal is 1.40239846 x 10^-45, 
 * and the largest value is 3.40282347 x 10^38.
 * Float range is much difference than the other primitive data type.
 * Its default value is 0.0f
 */
public class FloatPrimitiveDataType {

 public static void main(String[] args) {
	float floatVariable=9223.5f;
	System.out.println("Float value is : "+floatVariable);
		
 }
}

8) double primitive data type example:

package primitiveDataType;

/**
 * 
 * double is a primitive data type and takes 64 bits(8 byte) of memory
 * The range is 4.9406564584124654 x 10^-324 
 * to 1.7976931348623157 x 10^308. That range can
 * also be positive or negative.
 * Its default value is 0.0d
 */
public class DoublePrimitiveDataType {

 public static void main(String[] args) {
  double doubleVariable=9223.50006d;
  System.out.println("Double value is : "+doubleVariable);
 }
}

Note : You can download full source code from git repository https://github.com/firststepitsolution/java-core