Compile code in a file

Question

i have some java codes in my "fl.txt"(c:\fl.txt). these are;
public class file_{
public static void main(String args[]){
System.out.print("hello world");
}i want to compile these code from my program(i am building it with java) at runtime.. how can ii do that.i think i need to use runtime.exec() method but i dont know how can i compile these codes in a file....

Answer 1

It is possible to dynamically compile code from within a running Java program,
but you should have a damn good reason for doing so.
Check out the documentation for javac: http://java.sun.com/javase/6/docs/technotes/tools/windows/javac.html
<quote>
javac supports the new Java Compiler API defined by the classes and interfaces in the javax.tools package.
Example
To perform a compilation using arguments as you would give on the command line, you can use the following:
JavaCompiler javac = ToolProvider.getSystemJavaCompiler();
int rc = javac.run(null, null, null, args);This will write any diagnostics to the standard output stream, and return the exit code that javac would give when invoked from the command line.
You can use other methods on the javax.tools.JavaCompiler interface to handle diagnostics, control where files are read from and written to, and so on.
</quote>
If you are using an older version of Java, check out the documentation to see the old interface to do this (com.sun.tools.javac.Main).