What are Java primitive data types?

Java Primitive Data Types

In Java, primitive data types are the fundamental building blocks of the language. They are the basic data types that represent simple values, such as numbers, characters, and boolean values. Java has a total of eight primitive data types, which are:

1. byte: A 8-bit signed integer that can hold values from -128 to 127.
2. short: A 16-bit signed integer that can hold values from -32,768 to 32,767.
3. int: A 32-bit signed integer that can hold values from -2,147,483,648 to 2,147,483,647.
4. long: A 64-bit signed integer that can hold values from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807.
5. float: A 32-bit IEEE 754 floating-point number.
6. double: A 64-bit IEEE 754 floating-point number.
7. boolean: A 1-bit value that can be either true or false.
8. char: A 16-bit unsigned Unicode character that can hold values from '\u0000' (0) to '\uffff' (65,535).

Here's a Mermaid diagram that summarizes the Java primitive data types:

To illustrate the usage of primitive data types, let's consider a simple example where we declare and initialize variables of different primitive data types:

public class PrimitiveDataTypes {
    public static void main(String[] args) {
        byte b = 42;
        short s = 12345;
        int i = 1234567890;
        long l = 1234567890123456789L;
        float f = 3.14159f;
        double d = 3.14159265358979;
        boolean bool = true;
        char c = 'A';

        System.out.println("byte: " + b);
        System.out.println("short: " + s);
        System.out.println("int: " + i);
        System.out.println("long: " + l);
        System.out.println("float: " + f);
        System.out.println("double: " + d);
        System.out.println("boolean: " + bool);
        System.out.println("char: " + c);
    }
}

In this example, we declare and initialize variables of each primitive data type and then print their values to the console. The output of this program would be:

byte: 42
short: 12345
int: 1234567890
long: 1234567890123456789
float: 3.14159
double: 3.14159265358979
boolean: true
char: A

It's important to note that the choice of primitive data type depends on the specific requirements of your application, such as the range of values, memory usage, and performance considerations. Choosing the appropriate primitive data type can help optimize your Java code and ensure efficient memory usage.