001// ***************************************************************************************************************************
002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file *
003// * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file        *
004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
005// * with the License.  You may obtain a copy of the License at                                                              *
006// *                                                                                                                         *
007// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
008// *                                                                                                                         *
009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an  *
010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the        *
011// * specific language governing permissions and limitations under the License.                                              *
012// ***************************************************************************************************************************
013package org.apache.juneau.cp;
014
015import static org.apache.juneau.common.internal.ArgUtils.*;
016import static org.apache.juneau.internal.CollectionUtils.*;
017
018import java.util.*;
019
020/**
021 * A list of default implementation classes.
022 *
023 * <h5 class='section'>Notes:</h5><ul>
024 *    <li class='warn'>This class is not thread safe.
025 * </ul>
026 *
027 * <h5 class='section'>See Also:</h5><ul>
028 * </ul>
029 */
030public class DefaultClassList {
031
032   //-----------------------------------------------------------------------------------------------------------------
033   // Static
034   //-----------------------------------------------------------------------------------------------------------------
035
036   /**
037    * Static creator.
038    *
039    * @return A new object.
040    */
041   public static DefaultClassList create() {
042      return new DefaultClassList();
043   }
044
045   /**
046    * Static creator.
047    *
048    * @param values Initial entries in this list.
049    * @return A new object initialized with the specified values.
050    */
051   public static DefaultClassList of(Class<?>...values) {
052      return new DefaultClassList().add(values);
053   }
054
055   //-----------------------------------------------------------------------------------------------------------------
056   // Instance
057   //-----------------------------------------------------------------------------------------------------------------
058
059   private final List<Class<?>> entries;
060
061   /**
062    * Constructor.
063    */
064   protected DefaultClassList() {
065      entries = list();
066   }
067
068   /**
069    * Copy constructor
070    *
071    * @param value The object to copy.
072    */
073   public DefaultClassList(DefaultClassList value) {
074      entries = copyOf(value.entries);
075   }
076
077   /**
078    * Prepends the specified values to the beginning of this list.
079    *
080    * @param values The values to prepend to this list.
081    * @return This object.
082    */
083   public DefaultClassList add(Class<?>...values) {
084      prependAll(entries, values);
085      return this;
086   }
087
088   /**
089    * Returns the first class in this list which is a subclass of (or same as) the specified type.
090    *
091    * @param <T> The parent type.
092    * @param type The parent type to check for.
093    * @return The first class in this list which is a subclass of the specified type.
094    */
095   @SuppressWarnings("unchecked")
096   public <T> Optional<Class<? extends T>> get(Class<T> type) {
097      assertArgNotNull("type", type);
098      for (Class<?> e : entries)
099         if (e != null && type.isAssignableFrom(e))
100            return optional((Class<? extends T>)e);
101      return empty();
102   }
103
104   /**
105    * Creates a copy of this list.
106    *
107    * @return A copy of this list.
108    */
109   public DefaultClassList copy() {
110      return new DefaultClassList(this);
111   }
112}