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java data types

Data Types:-In java data types are divided into two parts.
  •  primitive data types
  •   secondary data types

Primitive data types:-there are total eight data types into java and there wrapper classes.

          
Data type
Wrapper classes
byte
Byte
short
Short
int
Integer
long
Long
float
Float
double
Double
char
Character
boolean
            Boolean

In the real world we have many types of data exist like 10,106,100,500.50, 100.10,”javaindore”,’A’,’5’, true and false.

Here 10,106 and 100=========whole number [byte, short, integer and long].
500.50 And 100.10===========floating number [float and double].
‘A’ and ‘5’              ============character [character].
true and  false     ============boolean [boolean].

Data Type
Keyword
Size
byte
byte
8bit
short
short
16bit
int
int
32bit
long
long
64bit
float
float
32bit
double
double
64bit
char
char
16bit
boolean
boolean
Not define
For data type we have to know only name of java data type only other things we can achieved by program.

Demo program for int data type,if we replace Integer to Byte then that will be demo program for byte data types,…….

class Test
{
public static void main(String[]args)
{
System.out.println(Integer.SIZE);                         //32   bit
System.out.println(Integer.BYTES);                    //4 byte
 System.out.println(Integer.MIN_VALUE);       //   -2,147,483,648
System.out.println(Integer.MAX_VALUE);    //      2,147,483,647
}
}


Above program will not work for Boolean class because of except Boolean class remaining all wrapper classes declared SIZE, BYTES, MIN_VALUE AND MAX_VALUE as a public static and final variable.


Example of Secondary data types are:-class,arrays,string......


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