I'm not sure what you're talking about.
You normally have some duplicates in $JAVA_HOME/bin and $JAVA_HOME/jre/bin.
$JAVA_HOME/bin contains mainly programs for development, while the jre/bin contains normal runtime-files, and you should remove: nothing.
I don't know jVisualStudio.net 2000, but afaik MS stopped their misleaded attempt j++ after a lawsuit, and now use something named j#.
This might be slightly related to java, but isn't java and isn't compatible.
Eclipse and JCreator are tools for java-development.
Eclipse is much more powerful than JCreator, but the last is suitable for small projects, and has lower hardware-requierements.
A syntax-highlightening, fast-starting editor like scintilla-scite is perfect for one-file-java-projects.
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