how to include an interface in java class

Question

I want to include an interface Printable to this class but it is showing an error.

error:Class file collision: A resource exists with a different case:     
'/example01/bin/com/example/test/test.class'.

This is my code

package com.example.test;

import com.example.test.Printable;

class A implements Printable {
    public void a() {
        System.out.println("a method");
    }

    @Override
    public void b() {

    }

}

abstract class B implements Printable {
    public void b() {
        System.out.println("b method");
    }

}

class Call {
    void invoke(Printable p) {// upcasting
        if (p instanceof A) {
            A a = (A) p;// Downcasting
            a.a();
        }
        if (p instanceof B) {
            B b = (B) p;// Downcasting
            b.b();
        }

    }
}// end of Call class

class Test {
    public static void main(String args[]) {
        Printable p = new A();
        Call c = new Call();
        c.invoke(p);
    }
}

This is my Printable interface class code

public interface Printable {

    public void a ();
    public void b();
}

So how can i import the interface Printable to this class any help would be appreciated. Thanks

error:Class file collision: A resource exists with a different case: '/example01/bin/com/example/test/test.class'. — Raghu
– Raghu, Commented Aug 8, 2014 at 12:09
Rebuild it, make sure all your classes/resources don't clash on name etc. — RossC
– RossC, Commented Aug 8, 2014 at 12:09
Here is the rule, at most 1 public(package local is also accepted) class per file. File name should match with class name inside file(case sensitive) — Admit
– Admit, Commented Aug 8, 2014 at 12:11

Community · Accepted Answer · 2017-05-23 10:26:17Z

2

This is my approach to embed a interface to a class:

public class NestedClassInterface {

/**
 * Nested interface
 * @author Markus
 */
public interface Printable {
    public void a();
}

/**
 * MAIN
 * @param args
 */
public static void main(String[] args) {
    Printable t = new MyTest();
    t.a();
}

/**
 * Static class (otherwise the compiler cannot find it)
 * @author Markus
 *
 */
public static class MyTest
implements Printable {
    public void a() {
        System.out.println("NestedClassInterface.MyTest.a()");
    }
}

}

Notes

As Admit highlights: There is only one (1) class allowed within a file. Naming should be consistent.
java.util.Map uses the same approach to have its entries defined Map.Entry: http://www.docjar.com/html/api/java/util/Map.java.html

Keep us posted on your progress.

edited May 23, 2017 at 10:26

CommunityBot

11 silver badge

answered Aug 8, 2014 at 12:31

Markus

7937 silver badges24 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

how to include an interface in java class

1 Answer 1

Notes

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Notes

Comments

Your Answer

Sign up or log in

Post as a guest

Related