A Caliper benchmark comparing different Java expression parsers / evaluators. Run it by executing:

com.blogspot.hypefree.fastexprbench.BenchmarkExpressionEvaluation

The compared libraries are:

• parsii
• Jeval
• JEPLite
• MathEval
• expr
• Janino ExpressionEvaluator
• A hand-rolled solution based on Janino

View results from my test-run here.

Read a more detailed explanation on the Transylvania JUG blog.