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A Lightweight Job Scheduling Framework forked from Quartz
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/**
 * Copyright 2015 Knowm Inc. (http://knowm.org) and contributors.
 * Copyright 2013-2015 Xeiam LLC (http://xeiam.com) and contributors.
 * Copyright 2001-2011 Terracotta Inc. (http://terracotta.org).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.quartz.classloading;

import java.io.InputStream;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Method;
import java.net.URL;

/**
 * A ClassLoadHelper that simply calls Class.forName(..).
 * 
 * @see org.quartz.classloading.ClassLoadHelper
 * @see org.quartz.classloading.ThreadContextClassLoadHelper
 * @see org.quartz.classloading.CascadingClassLoadHelper
 * @see org.quartz.classloading.LoadingLoaderClassLoadHelper
 * @author jhouse
 * @author pl47ypus
 */
class SimpleClassLoadHelper implements ClassLoadHelper {

  /*
   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Interface.
   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   */

  /**
   * Called to give the ClassLoadHelper a chance to initialize itself, including the opportunity to "steal" the class loader off of the calling
   * thread, which is the thread that is initializing Quartz.
   */
  @Override
  public void initialize() {

  }

  /**
   * Return the class with the given name.
   */
  @Override
  public Class loadClass(String name) throws ClassNotFoundException {

    return Class.forName(name);
  }

  /**
   * Finds a resource with a given name. This method returns null if no resource with this name is found.
   * 
   * @param name name of the desired resource
   * @return a java.net.URL object
   */
  @Override
  public URL getResource(String name) {

    return getClassLoader().getResource(name);
  }

  /**
   * Finds a resource with a given name. This method returns null if no resource with this name is found.
   * 
   * @param name name of the desired resource
   * @return a java.io.InputStream object
   */
  @Override
  public InputStream getResourceAsStream(String name) {

    return getClassLoader().getResourceAsStream(name);
  }

  /**
   * Enable sharing of the class-loader with 3rd party.
   * 
   * @return the class-loader user be the helper.
   */
  @Override
  public ClassLoader getClassLoader() {

    // To follow the same behavior of Class.forName(...) I had to play
    // dirty (Supported by Sun, IBM & BEA JVMs)
    try {
      // Get a reference to this class' class-loader
      ClassLoader cl = this.getClass().getClassLoader();
      // Create a method instance representing the protected
      // getCallerClassLoader method of class ClassLoader
      Method mthd = ClassLoader.class.getDeclaredMethod("getCallerClassLoader", new Class[0]);
      // Make the method accessible.
      AccessibleObject.setAccessible(new AccessibleObject[] { mthd }, true);
      // Try to get the caller's class-loader
      return (ClassLoader) mthd.invoke(cl, new Object[0]);
    } catch (Exception all) {
      // Use this class' class-loader
      return this.getClass().getClassLoader();
    }
  }

}