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    1   /*
    2    * $Id: ContainUtil.java 471756 2006-11-06 15:01:43Z husted $
    3    *
    4    * Licensed to the Apache Software Foundation (ASF) under one
    5    * or more contributor license agreements.  See the NOTICE file
    6    * distributed with this work for additional information
    7    * regarding copyright ownership.  The ASF licenses this file
    8    * to you under the Apache License, Version 2.0 (the
    9    * "License"); you may not use this file except in compliance
    10   * with the License.  You may obtain a copy of the License at
    11   *
    12   *  http://www.apache.org/licenses/LICENSE-2.0
    13   *
    14   * Unless required by applicable law or agreed to in writing,
    15   * software distributed under the License is distributed on an
    16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    17   * KIND, either express or implied.  See the License for the
    18   * specific language governing permissions and limitations
    19   * under the License.
    20   */
    21  package org.apache.struts2.util;
    22
    23  import java.lang.reflect.Array;
    24  import java.util.Collection;
    25  import java.util.Map;
    26
    27
    28  /***
    29   * <code>ContainUtil</code> will check if object 1 contains object 2.
    30   * Object 1 may be an Object, array, Collection, or a Map
    31   *
    32   * @version $Date: 2006-11-06 10:01:43 -0500 (Mon, 06 Nov 2006) $ $Id: ContainUtil.java 471756 2006-11-06 15:01:43Z husted $
    33   */
    34  public class ContainUtil {
    35
    36      /***
    37       * Determine if <code>obj2</code> exists in <code>obj1</code>.
    38       *
    39       * <table borer="1">
    40       *  <tr>
    41       *      <td>Type Of obj1</td>
    42       *      <td>Comparison type</td>
    43       *  </tr>
    44       *  <tr>
    45       *      <td>null<td>
    46       *      <td>always return false</td>
    47       *  </tr>
    48       *  <tr>
    49       *      <td>Map</td>
    50       *      <td>Map containsKey(obj2)</td>
    51       *  </tr>
    52       *  <tr>
    53       *      <td>Collection</td>
    54       *      <td>Collection contains(obj2)</td>
    55       *  </tr>
    56       *  <tr>
    57       *      <td>Array</td>
    58       *      <td>there's an array element (e) where e.equals(obj2)</td>
    59       *  </tr>
    60       *  <tr>
    61       *      <td>Object</td>
    62       *      <td>obj1.equals(obj2)</td>
    63       *  </tr>
    64       * </table>
    65       *
    66       *
    67       * @param obj1
    68       * @param obj2
    69       * @return
    70       */
    71      public static boolean contains(Object obj1, Object obj2) {
    72          if ((obj1 == null) || (obj2 == null)) {
    73              //log.debug("obj1 or obj2 are null.");
    74              return false;
    75          }
    76
    77          if (obj1 instanceof Map) {
    78              if (((Map) obj1).containsKey(obj2)) {
    79                  //log.debug("obj1 is a map and contains obj2");
    80                  return true;
    81              }
    82          } else if (obj1 instanceof Collection) {
    83              if (((Collection) obj1).contains(obj2)) {
    84                  //log.debug("obj1 is a collection and contains obj2");
    85                  return true;
    86              }
    87          } else if (obj1.getClass().isArray()) {
    88              for (int i = 0; i < Array.getLength(obj1); i++) {
    89                  Object value = null;
    90                  value = Array.get(obj1, i);
    91
    92                  if (value.equals(obj2)) {
    93                      //log.debug("obj1 is an array and contains obj2");
    94                      return true;
    95                  }
    96              }
    97          } else if (obj1.equals(obj2)) {
    98              //log.debug("obj1 is an object and equals obj2");
    99              return true;
    100         }
    101
    102         //log.debug("obj1 does not contain obj2: " + obj1 + ", " + obj2);
    103         return false;
    104     }
    105 }