final, finally, and finalize in Java

Here’s a breakdown of final, finally, and finalize in Java:

• final:
  • Purpose: Used as a keyword in variable, method, and class declarations.
  • Usage:
    • Variables: A final variable’s value cannot be changed once it’s initialized.

      final int MAX_VALUE = 100;
      

    • Methods: A final method cannot be overridden by subclasses.

      public final void show() {
          // Method body
      }
      

    • Classes: A final class cannot be subclassed.

      public final class Constants {
          // Class body
      }
      

• finally:
  • Purpose: Used with a try-catch block to execute code regardless of whether an exception is thrown or not.
  • Usage:

    try {
        // Code that might throw an exception
    } catch (Exception e) {
        // Exception handling code
    } finally {
        // Code that will always execute
    }
    

• finalize:
  • Purpose: A method used to perform cleanup operations before an object is garbage collected.
  • Usage: It’s a method defined in the Object class and can be overridden.

    protected void finalize() throws Throwable {
        try {
            // Cleanup code
        } finally {
            super.finalize();
        }
    }
    

In summary:

• final is a keyword used to define constants, prevent method overriding, and prevent inheritance.
• finally is a block used to execute code after try-catch, no matter the outcome.
• finalize is a method used to perform cleanup operations before garbage collection.

I hope this clears things up!