Just a theoretical question... Is java able to use .class runtime?

[Silver Ghost]

What I am trying to say is. For example. I have some program (call it server). And I want it to load and use a specific .class file. But I also want it to make it so, that when I change the .java file and recompile it into that .class file, and tell my server to reload the .class file it will do it.

Is it possible with Java?

[dlorde]

In principle, yes.

[Silver Ghost]

WEEEEEEEEE!

:)

Can you provide me with a link or something where I can read more about it?

[dlorde]

Sorry about the delay - I did reply earlier, but my post has just disappeared...

What you are asking is quite unusual - you will need to execute a command process to run javac to compile your class (and possibly jar to put it in a jar file). For this, see the Runtime (http://java.sun.com/j2se/1.4/docs/api/java/lang/Runtime.html) class and its exec() methods. You will also need to dynamically load and instantiate the modified class, for which you will need to use the Class (http://java.sun.com/j2se/1.4/docs/api/java/lang/Class.html) class, and possibly a custom ClassLoader (http://java.sun.com/j2se/1.4/docs/api/java/lang/ClassLoader.html).

I haven't tried reloading a modified class, but it may be problematic due to class loader problems. If so, you might find it easier to make the modifications as a subclass of the original and load that as a new class. The The JavaVirtual Machine Specification (http://java.sun.com/docs/books/vmspec/2nd-edition/html/ConstantPool.doc.html#72007) give details on the loading of classes at runtime.

Good luck :D