What are the differences between final, finally, and finalize in Java?

Question

Ravi Vishwakarma · Answer

final Keyword
The final the keyword is used to define constants and prevent method overriding, and inheritance. It can be applied to variables, methods, and classes.
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What is the difference between static and final keywords in Java?
finally Block
The finally block is used in conjunction with try and
catch blocks for exception handling. It ensures that a block of code is executed regardless of whether an exception is thrown or not. This is typically used for cleanup activities like closing files, releasing resources, etc.
public class Example {
    public static void main(String[] args) {
        try {
            int data = 25 / 5;
            System.out.println(data);
        } catch (ArithmeticException e) {
            System.out.println("Exception caught");
        } finally {
            System.out.println("Finally block is executed");
        }
    }
}
finalize Method
The finalize method is used to perform cleanup operations before an object is garbage collected. This method is defined in the Object class and can be overridden by subclasses. However, it is generally not recommended to rely on finalizing it for cleanup due to its unpredictability and performance costs.
public class Example {
    @Override
    protected void finalize() throws Throwable {
        try {
            System.out.println("finalize method called");
        } finally {
            super.finalize();
        }
    }
    public static void main(String[] args) {
        Example obj = new Example();
        obj = null;
        // Requesting JVM to call Garbage Collector method
        System.gc();
    }
}
Summary of Differences:
Feature
final
finally
finalize
Purpose
To define constants, prevent method overriding, and inheritance
To execute code regardless of exception handling
To perform cleanup before garbage collection
Usage
Applied to variables, methods, and classes
Used in a try-catch block
Method that can be overridden in a class
Context
Compile-time constant and inheritance control
Ensures code execution after try-catch block
Invoked by the garbage collector before object is reclaimed
Example
final int x = 10; and final void method() {} and final class MyClass {}
try { ... } catch (Exception e) { ... } finally { ... }
protected void finalize() throws Throwable { ... }
Bitwise AND, OR, XOR, and left/right shift operations.
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Feature	`final`	`finally`	`finalize`
Purpose	To define constants, prevent method overriding, and inheritance	To execute code regardless of exception handling	To perform cleanup before garbage collection
Usage	Applied to variables, methods, and classes	Used in a `try-catch` block	Method that can be overridden in a class
Context	Compile-time constant and inheritance control	Ensures code execution after try-catch block	Invoked by the garbage collector before object is reclaimed
Example	`final int x = 10;` `final void method() {}` `final class MyClass {}`	`try { ... } catch (Exception e) { ... } finally { ... }`	`protected void finalize() throws Throwable { ... }`

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What are the differences between final, finally, and finalize in Java?

Ravi Vishwakarma

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1 Answers

`final` Keyword

`finally` Block

`finalize` Method

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