Treemap 4.0.5 has problem with accepting .txt files as valid input
files. A quick remedy is to change the extension of your .txt file to .tm3.
The following error message has been observed by several users when trying to run Treemap.
java.lang.NoClassDefFoundError: javax/swing/JSpinner
at ControlPanel.initLegendTab(ControlPanel.java:1742)
at ControlPanel.(ControlPanel.java:308)
at TreemapProgram.fileOpen(TreemapProgram.java:992)
at TreemapProgram.chooseFile(TreemapProgram.java:389
at TreemapProgram.(TreemapProgram.java:163)
at TreemapProgramThread.run(TreemapProgram.java:1693)
If this is the case, make sure both J2SE version 1.4 or later is installed, and the
corresponding CLASSPATH is set properly.
