// ========================================================================
   // Copyright (c) 2009 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 org.eclipse.jetty.annotations;
  
  import java.lang.reflect.Method;
  import java.lang.reflect.Modifier;
  
  import javax.annotation.PreDestroy;
  
  import org.eclipse.jetty.annotations.AnnotationIntrospector.AbstractIntrospectableAnnotationHandler;
  import org.eclipse.jetty.plus.annotation.LifeCycleCallbackCollection;
  import org.eclipse.jetty.plus.annotation.PreDestroyCallback;
  import org.eclipse.jetty.webapp.MetaData;
  import org.eclipse.jetty.webapp.Origin;
  import org.eclipse.jetty.webapp.WebAppContext;
  
  public class PreDestroyAnnotationHandler extends AbstractIntrospectableAnnotationHandler
  {
      WebAppContext _context;
      
      public PreDestroyAnnotationHandler (WebAppContext wac)
      {
          super(true);
          _context = wac;
      }
  
      public void doHandle(Class clazz)
      { 
          //Check that the PreDestroy is on a class that we're interested in
          if (Util.isServletType(clazz))
          {
              Method[] methods = clazz.getDeclaredMethods();
              for (int i=0; i<methods.length; i++)
              {
                  Method m = (Method)methods[i];
                  if (m.isAnnotationPresent(PreDestroy.class))
                  {
                      if (m.getParameterTypes().length != 0)
                          throw new IllegalStateException(m+" has parameters");
                      if (m.getReturnType() != Void.TYPE)
                          throw new IllegalStateException(m+" is not void");
                      if (m.getExceptionTypes().length != 0)
                          throw new IllegalStateException(m+" throws checked exceptions");
                      if (Modifier.isStatic(m.getModifiers()))
                          throw new IllegalStateException(m+" is static");
                      
                      //ServletSpec 3.0 p80 If web.xml declares even one predestroy then all predestroys
                      //in fragments must be ignored. Otherwise, they are additive.                    
                      MetaData metaData = _context.getMetaData();
                      Origin origin = metaData.getOrigin("pre-destroy");
                      if (origin != null && 
                              (origin == Origin.WebXml ||
                               origin == Origin.WebDefaults || 
                               origin == Origin.WebOverride))
                              return;
                      
                      PreDestroyCallback callback = new PreDestroyCallback();
                      callback.setTarget(clazz.getName(), m.getName());
  
                      LifeCycleCallbackCollection lifecycles = (LifeCycleCallbackCollection)_context.getAttribute(LifeCycleCallbackCollection.LIFECYCLE_CALLBACK_COLLECTION);
                      if (lifecycles == null)
                      {
                          lifecycles = new LifeCycleCallbackCollection();
                          _context.setAttribute(LifeCycleCallbackCollection.LIFECYCLE_CALLBACK_COLLECTION, lifecycles);
                      }
  
                      lifecycles.add(callback);
                  }
              }
          }
      }
  }