package org.apache.maven.container;

 /*

  * 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.

  */

 import org.codehaus.plexus.PlexusContainer;

 import org.codehaus.plexus.component.repository.ComponentDescriptor;

 import java.util.HashMap;

 import java.util.LinkedHashMap;

 import java.util.Map;

 import java.util.Set;

 public class ContainerUtils

 {

     public static Set<String> findChildComponentHints( String role, PlexusContainer parent, PlexusContainer child )

     {

         return findChildComponents( role, parent, child ).keySet();

     }

     @SuppressWarnings( "unchecked" )

     public static Map<String, ComponentDescriptor> findChildComponents( String role, PlexusContainer parent, PlexusContainer child )

     {

         Map<String, ComponentDescriptor> parentComponents = parent.getComponentDescriptorMap( role );

         if ( parentComponents != null )

         {

             parentComponents = new LinkedHashMap<String, ComponentDescriptor>( parentComponents );

         }

         Map<String, ComponentDescriptor> childComponents = child.getComponentDescriptorMap( role );

         if ( childComponents == null )

         {

             return new HashMap<String, ComponentDescriptor>();

         }

         else

         {

             childComponents = new LinkedHashMap<String, ComponentDescriptor>( childComponents );

             if ( parentComponents != null && !parentComponents.isEmpty() )

             {

                 for ( Map.Entry<String, ComponentDescriptor> entry : parentComponents.entrySet() )

                 {

                     String hint = entry.getKey();

                     if ( childComponents.containsKey( hint ) && entry.getValue() == childComponents.get( hint ) )

                     {

                         childComponents.remove( hint );

                     }

                 }

             }

         }

         return childComponents;

     }

 }