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Data Types

                  A data type defines the size and type of value that a variable can store. Java provides two types

                  of data types: primitive and non-primitive.
                  Primitive Data Types

                  Java provides eight basic data types, as shown in the following table:

                                      Size
                   Data Type                              Minimum Value                     Maximum Value
                                    (in bits)
                   byte         8                 -128                               127

                   short        16                –32768                             32767
                   int          32                –2147483648                        2147483647

                   long         64                –9223372036854775808               9223372036854775807

                   char         16                0                                  65535

                   float        32                1.4E -45                           3.4028235E38

                   double       64                4.9E-324                           1.7976931348623157E308
                   boolean      1                 True or False

                  Non-Primitive Data Types

                  The non-primitive data types are derived from primitive data types. Non-primitive data types are
                  also known as reference data types. Some of the examples are class, interface, and array.
                  Literals


                  A literal denotes a constant value. Java has various types of literals. They are as follows:
                      Character Literal: A character literal is enclosed in single quotes and has exactly one character.
                     For example, ‘a’ is a character literal that means the letter a.
                      String Literal: A string literal is enclosed in double quotes. For example, “Hello World.”
                      Integer Literal: An integer literal is any number without a fraction. For example, 10 and 012

                      Floating-Point  Literal: Any number  with  decimal points, like 3.12, is treated  as a
                     floating-point literal.
                      Boolean Literal: Boolean literals can have either true or false values. They do not correspond
                     to 0 or 1 values as in C/C++.
                  Variables

                  Variables are  memory locations used to  store  values. When  a  variable  is created,  space is
                  allocated to it in the memory. This memory space is identified by the name that we give to the
                  variable. It is easy to create a variable in Java.
                  Declaring a Variable


                  In Java, a variable needs to be declared before use. Declaring a variable involves two steps: giving
                  the variable a name and stating what type of data is to be stored in the variable.

                  58     iPRIME (Ver. 2.2)–VIII
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