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//
//  ========================================================================
//  Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
//  ------------------------------------------------------------------------
//  All rights reserved. This program and the accompanying materials
//  are made available under the terms of the Eclipse Public License v1.0
//  and Apache License v2.0 which accompanies this distribution.
//
//      The Eclipse Public License is available at
//      http://www.eclipse.org/legal/epl-v10.html
//
//      The Apache License v2.0 is available at
//      http://www.opensource.org/licenses/apache2.0.php
//
//  You may elect to redistribute this code under either of these licenses.
//  ========================================================================
//

package com.firefly.utils.lang;

import java.net.URL;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

/**
 * ClassLoader Helper. This helper class allows classes to be loaded either from
 * the Thread's ContextClassLoader, the classloader of the derived class or the
 * system ClassLoader.
 *
 * Usage:
 * 
 *  * public class MyClass {
 *     void myMethod() {
 *          ...
 *          Class c=Loader.loadClass(this.getClass(),classname);
 *          ...
 *     }
 * 
 * 
 */
public class Loader {

	public static URL getResource(String name) {
		ClassLoader loader = Thread.currentThread().getContextClassLoader();
		return loader == null ? ClassLoader.getSystemResource(name) : loader.getResource(name);
	}

	/**
	 * Load a class.
	 * 
	 * Load a class either from the thread context classloader or if none, the
	 * system loader
	 * 
	 * 
	 * @param name
	 *            the name of the new class to load
	 * @return Class
	 * @throws ClassNotFoundException
	 *             if not able to find the class
	 */
	@SuppressWarnings("rawtypes")
	public static Class loadClass(String name) throws ClassNotFoundException {
		ClassLoader loader = Thread.currentThread().getContextClassLoader();
		return (loader == null) ? Class.forName(name) : loader.loadClass(name);
	}

	/**
	 * Load a class. Load a class from the same classloader as the passed
	 * loadClass, or if none then use {@link #loadClass(String)}
	 * 
	 * @param loaderClass
	 *            a similar class, belong in the same classloader of the desired
	 *            class to load
	 * @param name
	 *            the name of the new class to load
	 * @return Class
	 * @throws ClassNotFoundException
	 *             if not able to find the class
	 */
	@SuppressWarnings("rawtypes")
	public static Class loadClass(Class loaderClass, String name) throws ClassNotFoundException {
		if (loaderClass != null && loaderClass.getClassLoader() != null)
			return loaderClass.getClassLoader().loadClass(name);
		return loadClass(name);
	}

	public static ResourceBundle getResourceBundle(String name, boolean checkParents, Locale locale)
			throws MissingResourceException {
		ClassLoader loader = Thread.currentThread().getContextClassLoader();
		return loader == null ? ResourceBundle.getBundle(name, locale) : ResourceBundle.getBundle(name, locale, loader);
	}
}