1. Lecture 21 May 2, 2000

2. Exam 2 Post-Mortem Average grade was 69.3 –Median was 72, which means there were some very low scores that pulled down the average. There were 5 A’s, 6 B’s, 8 C’s, 5 D’s, and 8 F’s Answers to code questions on the web. Answers to short answers on your sheet.

3. FMQs Q 6: Remember, a subclass object is also a superclass object, but not vice-versa. –Update! I made a mistake on the answer key; the correct choice was E. (No wonder so many people missed it.) Q 23: You can define an anonymous class anywhere, even inside a parameter list in a method call. Q 25: An event object always gets passed to a callback method in Java. –A listener is an object has a callback method.

4. Review: TextEdit.java Read the file from disk into the TextArea. User edits the TextArea in memory (RAM). Write the file from the TextArea to the disk.

5. Project: MP3 Tag Editor Overview –Read an MP3 file from disk into memory. –User edits the tags in memory. –Write the MP3 file from memory to disk. GUI Design Goals –Use appropriate Components. –Use layout managers so the user can change the size of the main window.

6. MusicMatch Jukebox Download free copy: – http://www.musicmatch.comhttp://www.musicmatch.com Can play MP3 music files. Can generate MP3 music files from audio CDs. Maintains a “library” of your MP3 music files. –Provides an editor for your library. There are other MP3 programs available, such as winamp, realaudio jukebox, etc.

7. MP3 File Structure ID3V2 Tag (optional) Audio Information ID3V1 Tag (optional)