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.utils;
014
015import java.util.*;
016
017/**
018 * An extension of {@link LinkedHashSet} with a convenience {@link #append(Object)} method.
019 *
020 * <p>
021 * Primarily used for testing purposes for quickly creating populated sets.
022 * <p class='bcode w800'>
023 *    <jc>// Example:</jc>
024 *    Set&lt;String&gt; s = <jk>new</jk> ASet&lt;String&gt;().append(<js>"foo"</js>).append(<js>"bar"</js>);
025 * </p>
026 *
027 * @param <T> The entry type.
028 */
029@SuppressWarnings({"unchecked"})
030public final class ASet<T> extends LinkedHashSet<T> {
031
032   private static final long serialVersionUID = 1L;
033
034   /**
035    * Convenience method for creating a list of objects.
036    *
037    * @param t The initial values.
038    * @return A new list.
039    */
040   public static <T> ASet<T> create(T...t) {
041      return new ASet<T>().appendAll(t);
042   }
043
044   /**
045    * Adds an entry to this set.
046    *
047    * @param t The entry to add to this set.
048    * @return This object (for method chaining).
049    */
050   public ASet<T> append(T t) {
051      add(t);
052      return this;
053   }
054
055   /**
056    * Adds multiple entries to this set.
057    *
058    * @param t The entries to add to this set.
059    * @return This object (for method chaining).
060    */
061   public ASet<T> appendAll(T...t) {
062      addAll(Arrays.asList(t));
063      return this;
064   }
065
066   /**
067    * Adds a value to this set if the boolean value is <jk>true</jk>
068    *
069    * @param b The boolean value.
070    * @param t The value to add.
071    * @return This object (for method chaining).
072    */
073   public ASet<T> appendIf(boolean b, T t) {
074      if (b)
075         append(t);
076      return this;
077   }
078}