Can I convert a string to a math operation in java?

问题

can I convert a string like "3*3+3" to math operation in java??

回答1:

Evaluate it is as JavaScript using ScriptEngine

String xyz = "3*3+3";
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine se = manager.getEngineByName("JavaScript");        
Object result = se.eval(xyz);

Reference: Documentation

回答2:

There is no built-in function for that, you would have to implement a parser. However you could also look up for ready project, such as: http://sourceforge.net/projects/jep/ or http://code.google.com/p/symja/wiki/MathExpressionParser

来源：https://stackoverflow.com/questions/11577259/can-i-convert-a-string-to-a-math-operation-in-java