constant in Java

A constant is a variable whose value cannot change once it has been assigned. Java doesn't have built-in support for constants. A constant can make our program more easily read and understood by others. 
To define a variable as a constant, we just need to add the keyword “final” in front of the variable declaration.
```
public class Main
{
	public static void main(String[] args) {
		final int a = 0;
	}
}
```