Java Data Types

Data Type is a set of permitted value on which legal operation can be perform .In java  the variety of data types available allow the programmer to select  the appropriate to need of applications.

• Primitive (Intrinsic)
• Non Primitive (Derived)

1. Primitive (Intrinsic) :- 1.1. Numeric

                                  1.2. Non-Numeric

        1.1. Numeric:- 1.1.1. Integer

                              1.1.2. Floating Point

        1.2. Non- Numeric:- 1.2.1. Char

                                     1.2.2. Boolean

2. Non-Primitive (Derived):- 2.1. Class

                                      2.2. Array

                                      2.3. Interface

Data Types in java are two type.

• Primitive  Data type.
• Non Primitive Data.

 Primitive  Data type.  Primitive  Data type are predefined  data type , which always holds the value of the same  data type.

   Primitive  Data type are two type.

• Numeric Data Type.
• Nonnumeric Data Type.

  1. Numeric Data Type. Numeric Data Type are two type.

1. Integer.  java support four Types of Integers

• Byte
• Short
• int
• long.

2. Floating Point  type .   Floating Point  numbers, known as real numbers , are used when evaluating expressions that require fractional precision. For example , calculations such as square root, or transcendental such as  sine and cosine , results in a value whose precision require a floating point type. Floating Point  type two type .

• Float Type (Single Precision).
• Double Type ( Double  Precision).

2. Nonnumeric Type. Nonnumeric Primitive type are also two type .

• Char
• Boolean

1. Char:  A char is a single character, that is a letter, a digit, a punctuation mark, a tab, a space or something similar. A char literal is a single one character enclosed in single quote marks like this char Character = 'g'; In java char size 2 byte and range 0 to 65,536.

2. Boolean Type: Boolean Type is used when we want to test a particular condition during the execution of the program .Boolean have only two possible values ,true or false. Syntax: Boolean b;

2. Non Primitive (Reference Data Types): Reference data type  is a variable that can contain the reference or address of dynamically  created

object. The reference data types are  three type.

• classes
• array
• interface

1 . class type:   Class is a collection of java method and variable .A class is define by used of the 'class' keyword. syntax:

  class class_ name {

   type instance_variable1;

   type instance_variable2;

   type instance_variable3;

   ......................

  type method_ name ( parameter list )  {

        // body  of method

        }

}

2. Array:  Array is a collection of similar data type of contiguous memory allocation that share a common name.    syntax

type  array_ name[];

type[] array_ name;

3. Interface:   An Interface is a basically a kind of class . Interfaces define only abstract methods and final fields .  syntax

    interface interface_ name {

        variable declaration;

        method declaration;

    }