Attached is an application which fails to launch under 1.6 but
launched fine under 1.5 :

>>>>
  java16 -jar PracticeTools.jar
Exception in thread "main" java.lang.NoClassDefFoundError:
at/ofai/music/plot/WormPlot
         at java.lang.Class.getDeclaredMethods0(Native Method)
         at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
         at java.lang.Class.getDeclaredMethod(Class.java:1935)
         at
java.awt.Component.isCoalesceEventsOverriden(Component.java:5723)
         at
java.awt.Component.isCoalesceEventsOverriden(Component.java:5712)
         at java.awt.Component.access$100(Component.java:162)
         at java.awt.Component$2.run(Component.java:5677)
         at java.awt.Component$2.run(Component.java:5675)
         at java.security.AccessController.doPrivileged(Native Method)
         at java.awt.Component.checkCoalescing(Component.java:5674)
         at java.awt.Component.<init>(Component.java:5643)
         at java.awt.Container.<init>(Container.java:245)
         at java.awt.Window.<init>(Window.java:405)
         at java.awt.Frame.<init>(Frame.java:402)
         at java.awt.Frame.<init>(Frame.java:367)
         at javax.swing.JFrame.<init>(JFrame.java:163)
         at at.ofai.music.plot.Figure.<init>(Figure.java:100)
         at at.ofai.music.midisp.PracticeTools.<init>(PracticeTools.java:81)
         at at.ofai.music.midisp.PracticeTools.main(PracticeTools.java:437)
<<<<

It appears that several things contribute to this :

1. In 1.6 AWT now executes this code :
final Class<? extends Component> clazz = getClass();
clazz.getDeclaredMethod(
                "coalesceEvents", coalesceEventsParams
                );

2. It appears that the implementation of getDeclaredMethod()
in fact gets all methods and attempts to resolve all referenced classes.

3. at/ofai/music/plot/WormPlot is not in the jar file.

4. getDeclaredMethod() does not document that it might throw
NoClassDefFoundError.