Child First ClassLoader

ChildFirstClassLoader.java

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;

public class ChildFirstClassLoader extends URLClassLoader {
	private ClassLoader system;

	public ChildFirstClassLoader(URL[] classpath, ClassLoader parent) {
		super(classpath, parent);
		system = getSystemClassLoader();
	}

	@Override
	protected synchronized Class<?> loadClass(String name, boolean resolve)
	  throws ClassNotFoundException {
		// First, check if the class has already been loaded
		Class<?> c = findLoadedClass(name);
		if (c == null) {
			try {
				// checking local
				c = findClass(name);
			} catch (ClassNotFoundException e) {
				// checking parent
				// This call to loadClass may eventually call findClass
				// again, in case the parent doesn't find anything.
				try {
					c = super.loadClass(name, resolve);
				} catch (ClassNotFoundException e2) {
					if (system != null) {
                        // checking system: jvm classes, endorsed, cmd classpath,
                        // etc.
                        c = system.loadClass(name);
					}
				}
			}
		}
		if (resolve)
			resolveClass(c);
		return c;
	}

	@Override
	public URL getResource(String name) {
		URL url = findResource(name);
		if (url == null)
			url = super.getResource(name);

		if (url == null && system != null)
			url = system.getResource(name);

		return url;
	}

	@Override
	public Enumeration<URL> getResources(String name) throws IOException {
		/**
		 * Similar to super, but local resources are enumerated before parent
		 * resources
		 */
		Enumeration<URL> systemUrls = null;
		if (system != null) {
			systemUrls = system.getResources(name);
		}
		Enumeration<URL> localUrls = findResources(name);
		Enumeration<URL> parentUrls = null;
		if (getParent() != null) {
			parentUrls = getParent().getResources(name);
		}
		final List<URL> urls = new ArrayList<URL>();
		if (localUrls != null) {
			while (localUrls.hasMoreElements()) {
				URL local = localUrls.nextElement();
				urls.add(local);
			}
		}
		if (systemUrls != null) {
			while (systemUrls.hasMoreElements()) {
				urls.add(systemUrls.nextElement());
			}
		}
		if (parentUrls != null) {
			while (parentUrls.hasMoreElements()) {
				urls.add(parentUrls.nextElement());
			}
		}
		return new Enumeration<URL>() {
			Iterator<URL> iter = urls.iterator();

			public boolean hasMoreElements() {
				return iter.hasNext();
			}

			public URL nextElement() {
				return iter.next();
			}
		};
	}

	@Override
	public InputStream getResourceAsStream(String name) {
		URL url = getResource(name);
		try {
			return url != null ? url.openStream() : null;
		} catch (IOException e) {
		}
		return null;
	}
}

This triggers a SecurityException when the loader tries to load java.lang.
Maybe it should also catch SecurityException to fallback first on parent, then on system ?

https://gist.github.com/reda-alaoui/a3030964293268eca48ddc66d8a07d74