package org.codehaus.plexus.component.collections;
   
   /*
    * Copyright 2001-2006 Codehaus Foundation.
    *
    * 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.
   */
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Iterator;
  import java.util.List;
  import java.util.ListIterator;
  import java.util.Map;
  import java.util.Map.Entry;
  
  import org.codehaus.plexus.MutablePlexusContainer;
  import org.codehaus.plexus.component.repository.ComponentDescriptor;
  import org.codehaus.plexus.component.repository.exception.ComponentLifecycleException;
  
  /**
   * @author Jason van Zyl FIXME: [jdcasey] We need to review the efficiency (in speed and memory) of this collection...
   */
  public class ComponentList<T> extends AbstractComponentCollection<T> implements List<T> {
      private List<T> components;
  
      public ComponentList(
              MutablePlexusContainer container,
              Class<T> type,
              String role,
              List<String> roleHints,
              String hostComponent) {
          super(container, type, role, roleHints, hostComponent);
      }
  
      public int size() {
          return getComponentDescriptorMap().size();
      }
  
      public boolean isEmpty() {
          return getComponentDescriptorMap().isEmpty();
      }
  
      public boolean contains(Object object) {
          return getList().contains(object);
      }
  
      public Iterator<T> iterator() {
          return getList().iterator();
      }
  
      public Object[] toArray() {
          return getList().toArray();
      }
  
      public <X> X[] toArray(X[] ts) {
          return getList().toArray(ts);
      }
  
      public synchronized boolean add(T object) {
          getList().add(object);
  
          /*
           * PLX-352 This is strictly to support the hack in the Ant Run plugin that tries to poke in a custom converter.
           * We need a better way to register converters to plexus and not hit the default converter lookup directly.
           * throw new UnsupportedOperationException( "You cannot modify this list. This list is a requirement of " +
           * hostComponent + " and managed by the container." );
           */
  
          return true;
      }
  
      public boolean remove(Object object) {
          throw new UnsupportedOperationException("You cannot modify this list. This list is a requirement of "
                  + hostComponent + " and managed by the container.");
      }
  
      public boolean containsAll(Collection<?> collection) {
          return getList().containsAll(collection);
      }
  
      public boolean addAll(Collection<? extends T> collection) {
          throw new UnsupportedOperationException("You cannot modify this list. This list is a requirement of "
                  + hostComponent + " and managed by the container.");
      }
  
      public boolean addAll(int i, Collection<? extends T> collection) {
          throw new UnsupportedOperationException("You cannot modify this list. This list is a requirement of "
                  + hostComponent + " and managed by the container.");
     }
 
     public synchronized boolean removeAll(Collection<?> collection) {
         return getList().removeAll(collection);
     }
 
     public synchronized boolean retainAll(Collection<?> collection) {
         return getList().retainAll(collection);
     }
 
     public boolean equals(Object o) {
         if (this == o) {
             return true;
         }
         if (!(o instanceof List)) {
             return false;
         }
 
         List<?> other = (List<?>) o;
         return getList().equals(other);
     }
 
     public int hashCode() {
         return getList().hashCode();
     }
 
     public T get(int i) {
         return getList().get(i);
     }
 
     public T set(int i, T object) {
         throw new UnsupportedOperationException("You cannot modify this list. This list is a requirement of "
                 + hostComponent + " and managed by the container.");
     }
 
     public void add(int i, T object) {
         throw new UnsupportedOperationException("You cannot modify this list. This list is a requirement of "
                 + hostComponent + " and managed by the container.");
     }
 
     public T remove(int i) {
         throw new UnsupportedOperationException("You cannot modify this list. This list is a requirement of "
                 + hostComponent + " and managed by the container.");
     }
 
     public int indexOf(Object object) {
         return getList().indexOf(object);
     }
 
     public int lastIndexOf(Object object) {
         return getList().lastIndexOf(object);
     }
 
     public ListIterator<T> listIterator() {
         return getList().listIterator();
     }
 
     public ListIterator<T> listIterator(int index) {
         return getList().listIterator(index);
     }
 
     public List<T> subList(int fromIndex, int toIndex) {
         return getList().subList(fromIndex, toIndex);
     }
 
     private synchronized List<T> getList() {
         // NOTE: If we cache the component map, we have a problem with releasing any of the
         // components in this map...we need to be able to release them all.
         if ((components == null) || checkUpdate()) {
             List<T> componentList = new ArrayList<T>();
 
             Map<String, ComponentDescriptor<T>> descriptorMap = getComponentDescriptorMap();
 
             if (roleHints != null) {
                 // we must follow the order in roleHints
                 for (String roleHint : roleHints) {
                     ComponentDescriptor<T> componentDescriptor = descriptorMap.get(roleHint);
 
                     T component = lookup(componentDescriptor);
 
                     if (component != null) {
                         componentList.add(component);
                     }
                 }
             } else {
                 for (Entry<String, ComponentDescriptor<T>> entry : descriptorMap.entrySet()) {
                     ComponentDescriptor<T> componentDescriptor = entry.getValue();
 
                     T component = lookup(componentDescriptor);
 
                     if (component != null) {
                         componentList.add(component);
                     }
                 }
             }
             components = componentList;
         }
 
         return components;
     }
 
     @Override
     protected boolean checkUpdate() {
         if (super.checkUpdate()) {
             components = null;
 
             return true;
         }
 
         return false;
     }
 
     protected void releaseAllCallback() {
         if (components != null) {
             try {
                 container.releaseAll(components);
             } catch (ComponentLifecycleException e) {
                 logger.debug("Error releasing components in active collection: " + e.getMessage(), e);
             }
 
             components = null;
         }
     }
 }