What are the different types of Java data types ?

1.Definition:

• Primitive Data Types: These are the most basic data types in Java , predefined by the language itself. They specify the size and type of variable values, and there are eight primitive data types.
• Non-Primitive Data Types (Reference Types): These are user-defined types and refer to objects. They are created using classes, interfaces, and arrays .

2.Types and Example:

A.Primitive Data Types:

1.byte:

• • Example: byte age = 25;
  • Range: -128 to 127
  • Size: 1 byte (8 bits)
  • Usage: Useful for saving memory in large arrays where memory savings are needed.

2.short:

• • Example: short temperature = 1000;
  • Range: -32,768 to 32,767
  • Size: 2 bytes (16 bits)
  • Usage: Used for medium-range integers.

3.int:

• • Example: int salary = 50000;
  • Range: -2^31 to 2^31-1
  • Size: 4 bytes (32 bits)
  • Usage: Commonly used for integer variables in Java programs.

4.long:

• • Example: long distance = 100000000L;
  • Range: -2^63 to 2^63-1
  • Size: 8 bytes (64 bits)
  • Usage: Useful when a larger range than int is required.

5.float:

• • Example: float price = 19.99f;
  • Range: ~1.4e-45 to 3.4e38
  • Size: 4 bytes (32 bits)
  • Usage: Used for fractional numbers requiring less precision.

6.double:

• • Example: double weight = 70.5;
  • Range: ~4.9e-324 to 1.8e308
  • Size: 8 bytes (64 bits)
  • Usage: Used for decimal numbers needing more precision than float.

7.char:

• • Example: char grade = ‘A’;
  • Range: 0 to 65,535 (UNICODE characters)
  • Size: 2 bytes (16 bits)
  • Usage: Used to store single characters.

8.boolean:

• • Example: boolean isStudent = true;
  • Values: true or false
  • Size: Depends on JVM, but usually 1 bit.
  • Usage: Used for true/false conditions

B.Non-Primitive Data Types (Reference Types):

1.String:

• • Example: String name = “John”;
  • Description: Represents a sequence of characters.
  • Usage: Used to store text data.

2.Arrays:

• • Example: int[] numbers = {1, 2, 3};
  • Description: Represents a collection of variables of the same type.
  • Usage: Used for storing multiple values in a single variable.

3.Classes and Objects:

• • Example:
  • class Person {String name;

    int age;

    }

    Person person1 = new Person();

1. • Description: Defines the blueprint of an object in Java.
   • Usage: Used to define custom types (objects) that hold multiple related fields and methods.

4.Interfaces:

1. • Example:
   • interface Drawable {void draw();

     }

1. • Description: Defines a contract that classes must follow by implementing specific methods.

Features:

• Primitive Data Types:
  • Fixed size and predefined by Java.
  • Directly store values, not references.
  • Simple and efficient, offering fast performance.

• Non-Primitive Data Types:
  • Can store multiple values or more complex data.
  • Objects are created from these data types, and they store references, not actual values.
  • Allow flexibility in designing programs with custom types.

 Advantages:

• Primitive Data Types:
  • Faster because they hold the actual values.
  • Less memory overhead compared to objects.

• Non-Primitive Data Types:
  • More versatile, allowing the creation of complex data structures like strings , arrays, and objects.
  • Support rich functionalities through built-in methods (e.g., String has methods like length() and substring()).

Uses:

• Primitive Data Types:
  • int: Used for counting, loops, array indices, etc.
  • boolean: Used for conditions in control flow (if, while, etc.).
  • char: Used for handling characters, e.g., processing text.

• Non-Primitive Data Types:
  • String: Used in applications for text processing, input/output, and user interaction.
  • Arrays: Used when handling multiple items of the same type, e.g., storing a list of numbers.
  • Objects: Used to represent entities in object-oriented programming (OOP), such as a Person or Car in a simulation.