Description Adrian 2007-09-28 04:49:14 EDT

Created attachment 79356 [details]
Package Explorer showing a false inherited overridden method

Suppose we have the following two classes defined in two different packages, generic and implementation:

package generic;

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



and


package implementation;

public class A extends generic.A {
    public void method(A a) {
        System.out.println("implementation.A(implementation.A)");
    }
}


Please note the followings:
- class implementation.A extends the class generic.A
- the method generic.A.method takes an argument of type generic.A
- the method implementation.A.method takes an argument of type implementation.A
- therefore the method implementation.A.method does NOT override the method generic.A.method since their signatures are not the same (different parameter types)

But, when looking in Package explorer, we can see that the Eclipse workbench shows that the method implementation.A.method overrides the method generic.A.method, although this is false. If we open the class implementation.A in the editor, there is no sign on the left that the method would be overridden, which is correct. Please see the attached file package_explorer_view.JPG

The same in the hierarchy view when selecting implementation.A.method and pressing "Lock view and show members in hierarchy" button. Please see the attached file hierarchy_view.jpg

Suppose we define the following test class in the default package (or whatever):

public class B {
    public static void main(String[] args) {
        generic.A a1 = new generic.A();
        a1.method(a1);
    }
}

Please note the followings:
- the class B _does not use_ the class implementation.A
- the class B _uses_ the class generic.A
- the class B invokes the method generic.A.method

When we open the class implementation.A and we perform a search for references in the workspace for the method implementation.A.method, then there is one reference found, in the class B, method main, which is obviously false, class B never uses implementation.A.method. 
Please see the attached file search_view.JPG