I found java.lang.ExceptionInInitializerError was occured in JApplet.setLayout()
, when I run a applet extended JApplet.
The CODEBASE parameter in APPLET tag seems wrong, because the same applet
worked fine when I removed CODEBASE parameter.
Same exception was occured when I used ARCHIVE parameter in APPLET tag.

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gotzman{jun}93% javac -d classes JAppletTest.java
gotzman{jun}94% appletviewer test.html
java.lang.ExceptionInInitializerError
        at java.awt.swing.JApplet.setLayout(JApplet.java:247)
        at java.awt.swing.JApplet.<init>(JApplet.java:97)
        at JAppletTest.<init>(JAppletTest.java:5)
        at java.lang.Class.newInstance(Native Method)
        at sun.applet.AppletPanel.createApplet(AppletPanel.java:459)
        at sun.applet.AppletPanel.runLoader(AppletPanel.java:395)
        at sun.applet.AppletPanel.run(AppletPanel.java:234)
        at java.lang.Thread.run(Thread.java:490)