- Trending Categories
- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How can we use this and super keywords in method reference in Java?
The method reference is similar to a lambda expression that refers to a method without executing it and "::" operator can be used to separate a method name from the name of an object or class in a method reference.
The methods can be referenced with the help of this and super keywords in Java. The super keyword can be used as a qualifier to invoke the overridden method in a class or an interface.
syntax
this::instanceMethod TypeName.super::instanceMethod
Example
import java.util.function.Function; interface Defaults { default int doMath(int a) { return 2 * a; } } public class Calculator implements Defaults { @Override public int doMath(int a) { return a * a; } public void test(int value) { Function<Integer, Integer> operator1 = this::doMath; System.out.println("this::doMath() = " + operator1.apply(value)); Function<Integer, Integer> operator2 = Defaults.super::doMath; System.out.println("Defaults.super::doMath() = " + operator2.apply(value)); } public static void main(String[] args) { Calculator calc = new Calculator(); calc.test(10); } }
Output
this::doMath() = 100 Defaults.super::doMath() = 20
Advertisements