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FAQ About CodeWarrior


Why can't I load a file into CodeWarrior and compile it?

You cannot compile a .java file unless it is part of a project. You can't simply open the .java file in CodeWarrior and then compile it.

For your own sake, please remember to put each CodeWarrior project in its own folder (directory). If you don't keep things organized, you will get confused later on.

My program won't compile. It says exception in thread "main" java.lang.NoClassDefFoundError: MyJLiveWindow

CodeWarrior has to know which class contains method main. You haven't told it. You can find out how to do this by listening to the second activity on the fourth page of the CodeWarrior tutorial on ProgramLive.

I listened to the activity and did what it said; I told CodeWarrior that the class that contains method main is, and it still doesn't work!

You have to tell it the name of the class, MyJLiveWindow, and not the name of the file,

When I use stationary to start CodeWarrior, the class with method main is TrivialApplication. I don't like this name; can I change it?

Yes, when CodeWarrior creates a project using stationEry (not stationAry), the class with method main has name TrivialApplication. You can change the name of this file to something else as follows, assuming that you have the project open in CodeWarrior:

  1. Open file TrivialApplication and edit it: change the name of the class from TrivialApplication to MyName (whichever name you want).
  2. Use menu File item SaveAs to save the file with the name Make sure the new file is placed in the project folder; you may have to navigate in the file dialog box to get this to happen. Note that this new file appears in the project window instead of
  3. Change the name of the class that contains method main to MyName (as discussed in the
    second activity of page 4 of the CodeWarrior Lesson of ProgramLive).

Why doesn't program Draw1 close when you click the close box in its graphics window? (This is the program that you make using files and; class Draw1 contains method main. You can get these files from ProgramLive using menu Tools item List Programs, clicking Title input/output, and clicking button Folder.)

It doesn't close because we didn't program it to do that. In the next edition of ProgramLive, we will. Later in the course, we may have time to show YOU how to do that!

On the Macintosh, you can close program execution by choosing "Quit" from the Apple menu or by hitting keys Command-Q. On the PC, click the close box in the Java console. You can use ctrl-alt-del, but that's messy.