JEval
JEval is an advanced library for adding high-performance, mathematical, Boolean and functional expression parsing and evaluation to your Java applications. Features include: parses and evaluates dynamic and static expressions at run time, supports all major mathematical and Boolean operators, supports custom functions, 39 Math and String functions built in and ready to use, supports nested functions, supports variables, allows for custom variable resolver, no dependencies to other non-standard Java libraries, compatible with J2SE 1.2 and above.
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License
Apache Software License