Implementing Interfaces in Java classes

The syntax for implementing an interface makes use of this pattern:

... implements InterfaceName[, another interface, another, ...] ...

Classes may implement an interface. For example:


    public class Lion implements Predator
    {

        @Override
        public boolean chasePrey(Prey p)
        {
               // programming to  chase prey p (specifically for a lion)
        }

        @Override
        public void eatPrey(Prey p)
        {
               // programming to eat prey p (specifically for a lion)
        }
     }
    

If a class implements an interface and does not implement all its methods, it must be marked as abstract. If a class is abstract, one of its subclasses is expected to implement its unimplemented methods. Although if any of the abstract class' subclasses does not implement all interface methods, the subclass itself must be marked again as abstract.

Classes can implement multiple interfaces:


     public class Frog implements Predator, Prey { ... }
    

Interfaces can share common class methods:


     class Animal implements LikesFood, LikesWater
     
 {
 boolean likes() {return true;}
 }
    

However a given class cannot implement the same or a similar interface multiple times:


     
     class Animal implements Shares, Shares ...
    

Interfaces are commonly used in the Java language for callbacks, as Java does not allow multiple inheritance of classes, nor does it allow the passing of methods (procedures) as arguments. Therefore, in order to pass a method as a parameter to a target method, current practice is to define and pass a reference to an interface as a means of supplying the signature and address of the parameter method to the target method rather than defining multiple variants of the target method to accommodate each possible calling class.

References : Wikipedia share on :        :  

Love to hear your Views / Guidance / Recommendations on this Post…

Explore the Technology World

Computer Programming Terminologies Computer Programming Terminology is a general word for the group of specialized words or meanings relating to Computer Programming, and also the study of such t ...Read MoreNew features in JDK 12 with IntelliJ IDEADeveloped by JetBrains (formerly known as IntelliJ) ,IntelliJ IDEA is a Java integrated development environment (IDE) for developing computer software. It is av ...Read MoreGoogle Pay API Implementation Demo for AndroidIn this youtube Channel by Android Developers ,Learn how to implement the Google Pay API for Android with just a few lines of code and how it works with your ex ...Read MoreUnit Testing in .NET Core and Azure Devops pipelineUnit testing is a software testing method by which individual units of source code, usage procedures,sets of one or more computer program modules together with ...Read MoreThe mind behind Linux & GIT : Linus TorvaldsLinus Torvalds transformed technology twice — first with the Linux kernel, which helps power the Internet, and again with Git, the source code management ...Read MoreTensorflow and deep learningWith Tensorflow ,deep machine learning transitions from an area of research into mainstream software engineering. ...Read MoreJava program to return all possible permutations from collection of distinct numbersexample of Java program to return all possible permutations from collection of distinct numbers ...Read MoreReal Time Analytics with Spring Application Development FrameworkSpring is the most popular application development framework for enterprise Java.Millions of developers use Spring to build simple, truly portable, fast and fle ...Read MorePath Setting in Java When an application is launched from command prompt Windows OS searches for the executable program in the current working directory. The prompt throws an error ...Read MoreFacebook | whatsapp|Github | Twitter | LinkedIn | Youtube| reddit About | Cookies-Policy | Disclaimer | Site Map | Contact

Call / Visit for New Batch

Services

Why Join Us

  • ➯ Free Demo Classes
  • ➯ No Registration Fee
  • ➯ Interview Questions
  • ➯ Study Materials
  • ➯ Softwares
  • ➯ Aptitude & Reasoning
  • ➯ Placement Assitance

Address

  • MyJava Training Institute ,
  • Plot No.243 , shop No 14 ,
  • Secnd Floor , Zone-II ,
  • M.P.Nagar , Bhopal,
  • Madhya Pradesh ( 462011 )
  • ☎  08871209400 , 7987028543
  • 🌐 www.myjava.in
FacebookGoogle +TwitterYouTube

MyJava - java Training Institute