Final variable in java|Blank final variable in java|Final variable with example in java

                          Final variables in Java

In Java, when final keyword is used with a variable of primitive data types (int, float, .. etc), value of the variable cannot be changed.

Fig: Final variable | Local variable

For example following program gives error because i is final

public class Test {

          public static void main(String args[]) {

                   final int i = 10;

                   i = 30; // Error because i is final.

          }

}

When final is used with non-primitive variables (Note that non-primitive variables are always references to objects in Java), the members of the referred object can be changed. final for non-primitive variables just mean that they cannot be changed to refer to any other object.

class Test1 {

int i = 10;

}

public class Test2 {

          public static void main(String args[]) {

          final Test1 t1 = new Test1();

          t1.i = 30; // Works

          }

}

Fig: Final variable and method