BEEJ is a Boolean Expression Editor for Java.
It provides a GUI Swing interface to use in existing applications. After subclassing an ExpressionPanel (it provides the basic criteria options, like combo boxes and text boxes), simple instantiate an ExpressionEditor and place it in an existing application. The ExpressionEditor then allows the user to easily construct simple or complex boolean clauses.
Theoretically, expressions of any type (not just boolean) can be constructed using this library.
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