ClassNotFoundException loading runtime compiled subclass

Question

I am using JavaCompiler to compile CustomProcessor.java from within a web application at runtime

package com.notmycompany;

import com.mycompany.Processor;
import com.mycompany.Event;

public class CustomProcessor extends Processor {

    @Override
    public void process( Event evt) {
        // Do you own stuff
        System.out.println( "My Own Stuff");
    }
}

Compilation goes well, I end up with a class file that I am trying to load using URLClassLoader

URL[] urls = new URL[]{ new URL("file://d:/temp/") }; 
URLClassLoader ucl = new URLClassLoader(urls);
Class clazz = ucl.loadClass("com.notmycompany.CustomProcessor");

The problem is I am hitting a ClassNotFoundException on Processor which I am using elsewhere in the application (as in I known it's there).
What do I need to do so com.mycompany.Processor is visible at runtime?

Caused by: java.lang.ClassNotFoundException: com.mycompany.Processor
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 30 more

Thanks.

Answer 1

It is a matter of using a URLClassLoader fed with a complete classpath
As per this question I used

URLClassLoader ucl2 = new URLClassLoader( new URL[] { new URL( "file://d:/temp/")}, urlClassLoader);
Class<?> clazz = ucl2.loadClass("com.notmycompany.CustomProcessor");