Thread: General Question on Interfaces

Hello everyone,
Looking for someone who will be so kind as too possible give me their interpretation of what an interface is good for.
I need to implement one in my assignment and no matter what I read, video's I watch, etc. I am still confused on what the are actually good for.

I am just practicing with it before implementing it in my assignment so this is what I have,

package interfacesamplecode;
 
public interface highScores {
 
   String name = "John";
   int score = 150;
 
    void allScores(String name, int score);
}

package interfacesamplecode;
 
public class InterfaceSampleCode implements highScores {
 
        @Override
    public void allScores(String name, int score) {
            System.out.println(highScores.name);
            System.out.println(highScores.score);
    }
 
 
    public static void main(String[] args) {       
        InterfaceSampleCode newHighScore = new InterfaceSampleCode();      
        newHighScore.allScores(name, score);
    }
}

 

run:

John

150

BUILD SUCCESSFUL (total time: 0 seconds)

To me it seems like you can get the same results if you have the String variables in just another class and you call that class, or even extend that class. You should be able to get the same results, this is were I am having trouble understanding what an interface would actually be good for.

If you can, could you give some real world examples on how they could improve a Java program.

Not looking for any code, just why one would use them.

Thanks,

what an interface is good for.

Look at the APIs examples: ActionListener, List and Map and many others
They allow a class to tell the world what set of methods it supports.
One class can implement many interfaces.


See the tutorial: https://docs.oracle.com/javase/tutor...interface.html

A class that does not call any other classes would probably not need any interfaces.