如何在j2me midp 2.0中评估基于字符串的公式？

Question

I working in j2me(midp2.0) platform.I have received a formula String from a server like status=completed-defects along with table data.

the above status, completed, defects are table columns.so,in the status column i want to put the above formula.So, for doing this, i can able to get the value of the completed and defect column and modified the above formula as "=50-40".now i want to evaluate this Strings.Does anybody having the solution to please guide me to get this problem...

Operators are fixed : + , - , * , / , % , ( , ) and there is no limit for operators.

Answer 1

Java Math Expression Evaluator makes exactly what you need. It supports following functions: +, -, *, /, ^, %, cos, sin, tan, acos, asin, atan, sqrt, sqr, log, min, max, ceil, floor, abs, neg, rndr.

Sample:

MathEvaluator m = new MathEvaluator("-5-6/(-2) + sqr(15+x)");
m.addVariable("x", 15.1d);
System.out.println( m.getValue() );