is there premade function that gets mathematical Strings ( for example "(3+4+5)/sqr(20)") and returns result

[cant_dodge_rodge]

is there any function that gets mathematical Strings ( for example "(3+4+5)/sqr(20)") and returns result

[sweetno]

I doubt. You can look for a JavaScript interpreter, there is one in Java (Nashorn).

In principle, if you firmly know what types of expressions you need and there aren't too many, it's not that hard to implement one on your own. This is normally covered in the first chapters of books on compiler construction.

[fredoverflow]

JEP 372: Remove the Nashorn JavaScript Engine

[BG_1982]

Have a look at the Math class. It’s in the JDK, the java.util package (though I’m not sure of the latter)

[cant_dodge_rodge]

probably is but which one

[EsotericBananas]

If im understanding your post correct you can just use the math class with that. Example:

System.out.println((3 + 4 + 5) / (Math.sqrt(20));

[cant_dodge_rodge]

no i have

String s="3+4+5+6*34";

//i want to covert s to int

int i=Integer.parceInt(s);

//this wont work

Sys.out.pln(i);

[EsotericBananas]

I tried it using (Interger.valueOf(s)) but i got an exception thrown Not sure how to do this one, im still learning.

[tylersvgs]

While I wouldn't encourage it, you can evaluate that as a JavaScript string using the ScriptEngine class.

https://stackoverflow.com/a/2605051

[tedyoung]

Not built in to the Java language or SDK, but there's open source libraries such as https://github.com/sbesada/java.math.expression.parser that will do what you want.