/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.aries.util.internal;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import org.osgi.framework.Bundle;
import org.osgi.framework.FrameworkUtil;

public final class FelixWorker extends DefaultWorker implements FrameworkUtilWorker 
{
  private static Method getCurrentModuleMethod;
  private static Method getClassLoader;
  private static Class<?> moduleClass;

  static {
    Bundle b = FrameworkUtil.getBundle(FelixWorker.class);
    try {
      getCurrentModuleMethod = b.getClass().getDeclaredMethod("getCurrentModule");
      moduleClass = b.getClass().getClassLoader().loadClass("org.apache.felix.framework.ModuleImpl");
      getClassLoader = moduleClass.getDeclaredMethod("getClassLoader");
      
      getCurrentModuleMethod.setAccessible(true);
      getClassLoader.setAccessible(true);
    } catch (SecurityException e) {
    } catch (NoSuchMethodException e) {
    } catch (IllegalArgumentException e) {
    } catch (ClassNotFoundException e) {
    }
  }
  
  public ClassLoader getClassLoader(Bundle b) 
  {
    if (getCurrentModuleMethod != null) {
      try {
        Object result = getCurrentModuleMethod.invoke(b);
        if (result != null && moduleClass.isInstance(result)) {
          Object cl = getClassLoader.invoke(result);
          
          if (cl instanceof ClassLoader) return (ClassLoader) cl;
        }
      } catch (IllegalArgumentException e) {
      } catch (IllegalAccessException e) {
      } catch (InvocationTargetException e) {
      }
    }
    return null;
  }

  public boolean isValid()
  {
    return getCurrentModuleMethod != null && moduleClass != null && getClassLoader != null;
  }
}
