Sunday, May 27, 2012

"Must Override a Superclass Method" Errors after importing a project into Eclipse


Anytime I have to re-import my projects into Eclipse (if I reinstalled Eclipse, or changed the location of the projects), almost all of my overridden methods are not formatted correctly, causing the error ' The method ?????????? must override a superclass method '.



It may be noteworthy to mention this is with Android projects - for whatever reason, the method argument values are not always populated, so I have to manually populate them myself. For instance:




list.setOnCreateContextMenuListener(new OnCreateContextMenuListener() {

public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
//These arguments have their correct names
}


});



will be initially populated like this:




list.setOnCreateContextMenuListener(new OnCreateContextMenuListener() {

public void onCreateContextMenu(ContextMenu arg1, View arg2,
ContextMenuInfo arg3) {
//This methods arguments were not automatically provided
}


});



The odd thing is, if I remove my code, and have Eclipse automatically recreate the method, it uses the same argument names I already had, so I don't really know where the problem is, other then it auto-formatting the method for me.



This becomes quite a pain having to manually recreate ALL my overridden methods by hand. If anyone can explain why this happens or how to fix it .. I would be very happy.



Maybe it is due to the way I am formatting the methods, which are inside an argument of another method?


Source: Tips4all

5 comments:

  1. Eclipse is defaulting to Java 1.5 and you have classes implementing interface methods (which in Java 1.6 can be annotated with @Override, but in Java 1.5 can only be applied to methods overriding a superclass method).

    Go to your project/ide preferences and set the java compiler level to 1.6 and also make sure you select JRE 1.6 to execute your program from eclipse.

    ReplyDelete
  2. With Eclipse Galileo you go to Eclipse -> Preferences menu item, then select Java and Compiler in the dialog.

    Now it still may show compiler compliance level at 1.6, yet you still see this problem. So now select the link "Configure Project Specific Settings..." and in there you'll see the project is set to 1.5, now change this to 1.6. You'll need to do this for all affected projects.

    This byzantine menu / dialog interface is typical of Eclipse's poor UI design.

    ReplyDelete
  3. In case this happens to anyone else who tried both alphazero and Paul's method and still didn't work.

    For me, eclipse somehow 'cached' the compile errors even after doing a Project > Clean...

    I had to uncheck Project > Build Automatically, do a clean and build again.

    ReplyDelete
  4. To resolve this issue
    Go to your project properties->java compiler-> select compiler compliance level to 1.6->apply.

    --
    Cheers
    Venu

    ReplyDelete
  5. Guys in my case none of the solutions above worked.

    I had to delete the files within the Project workspace:


    .project
    .classpath


    And the folder:


    .settings


    Then I copied the ones from a similar project that was working before. This managed to fix my broken project.

    Of course do not use this method before trying the previous alternatives!.

    ReplyDelete