Java2Demo applet malfunctions after restart in appletviewer

Java2Demo occasionally throws "java.lang.NullPointerException" on "Stop"/"Restart" in appletviewer when the just in time (JIT) compiler is disabled. The issue with NPE could not be reproduced by the user with the enabled JIT compiler.

Full JRE/JDK Versions
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All: Tested with the latest JDK 8 (JDK 8u25), and all the way back to JDK 5.0

System Configuration
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Generic: Tested on Windows and Linux

Testcase & Reproduction Instructions
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1. Run: appletviewer Java2Demo.html
2. After applet has started, click Applet->Restart
3. Click the tabs and note that the program is not working properly - the tabs do not switch.