Final Local Variable in Java

Local Variable

• Local variables are declared in methods, constructors, or blocks.

• Local variables are created when the method, constructor or block is entered and the variable will be destroyed once it exits the method, constructor, or block.

• Access modifiers cannot be used for local variables.

• Local variables are visible only within the declared method, constructor, or block.

• Local variables are implemented at stack level internally.

• There is no default value for local variables, so local variables should be declared and an initial value should be assigned before the first use.

final Local Variable

• final is the only allowed access modifier for local variables.

• final local variable is not required to be initialized during declaration.

• final local variable allows compiler to generate an optimized code.

• final local variable can be used by anonymous inner class or in anonymous methods.

Example

abstract class AnonymousInner {
   public abstract void display();
}

public class Tester {
   public static void main(String args[]) {

      final int value;
      value = 100;
      AnonymousInner inner = new AnonymousInner() {
         public void display() {
            System.out.println("Accessing value: " + value);
         }
      };
      inner.display();
   }
}

Output

Accessing value: 100