Java Data Types

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 Java is a strongly typed language, which means that each variable must be declared with a specific data type. Java has two categories of data types: primitive and reference.

Primitive data types are the basic data types in Java and are used to represent simple values like numbers, characters, and boolean values. There are eight primitive data types in Java:

  1. byte - 8-bit signed two's complement integer (-128 to 127)
  2. short - 16-bit signed two's complement integer (-32,768 to 32,767)
  3. int - 32-bit signed two's complement integer (-2,147,483,648 to 2,147,483,647)
  4. long - 64-bit signed two's complement integer (-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807)
  5. float - 32-bit IEEE 754 floating point (single precision)
  6. double - 64-bit IEEE 754 floating point (double precision)
  7. char - 16-bit Unicode character (0 to 65,535)
  8. boolean - true/false value

Reference data types are used to refer to objects and are allocated memory at runtime. Some common reference types include:

  1. String - a sequence of characters
  2. Arrays - a collection of elements of the same data type
  3. Classes - a blueprint for creating objects
  4. Interfaces - a collection of abstract methods that define a contract for classes to implement
  5. Enumerations - a special kind of class used to define a set of constants

In addition to these, Java also has some other special data types like void, which represents no value.

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