Java: Can I Code in a String?

Question

Possible Duplicate:
Executing java code given in a text file
using eval in Java

I have written a Java program, and I was wondering if I can do Java in a String. For example, let's say I have the following:

String s = "int i = 1;";

In the String above, I have a Java command in it. Can I execute the Command outside the String in my actual program?

This question is answered in the following question: http://stackoverflow.com/questions/935175/convert-string-to-code — ajon, Sep 18 '12 at 20:23
I'd say, yes & no. Yes you can do dynamic compilation, but, probably not the way you're trying (I'd be happy to be wrong). Take a read through [Generating Java classes dynamically through Java compiler API](http://www.accordess.com/wpblog/an-overview-of-java-compilation-api-jsr-199/) to start with (first link off Google) — MadProgrammer, Sep 18 '12 at 20:25
Why do you need that? Are you forced to work with Java? Maybe a dynamic language supporting eval is what you are looking for, even though I discourage doing something like that as it makes your code much harder to understand and maintain — mariosangiorgio, Sep 18 '12 at 20:28

score 3 · Answer 1 · answered Sep 18 '12 at 20:26

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You would be able to do this with something like BeanShell.

answered Sep 18 '12 at 20:26

Tim Bender

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I agree, +1. Much safer than compiling and running using the compiler API – Brian Sep 18 '12 at 20:27

score 1 · Answer 2 · edited May 23 '17 at 12:12

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No, you cannot enter code into a String like that. The " symbol essentially delimits the real code from a String.

Once you type in String xyz = you are creating a variable, and what comes next needs to be a STring value. Maybe later you can do something with that, but as of now it's not execcutable

You might like to brush up on Strings:

Java String Class

Quotation marks inside a string

edited May 23 '17 at 12:12

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answered Sep 18 '12 at 20:22

Caffeinated

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score 1 · Answer 3 · edited May 23 '17 at 12:27

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While parsing Java like that might be tricky you could use something like Rhino to evaluate JavaScript in a string. This might be a bit outside of what you are asking though.

edited May 23 '17 at 12:27

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answered Sep 18 '12 at 20:24

Jason Sperske

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Java: Can I Code in a String?

3 Answers3