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    1   /*
    2    * $Id: PortletSessionMap.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.portlet;
    22
    23  import java.util.AbstractMap;
    24  import java.util.Enumeration;
    25  import java.util.HashSet;
    26  import java.util.Map;
    27  import java.util.Set;
    28
    29  import javax.portlet.PortletRequest;
    30  import javax.portlet.PortletSession;
    31
    32  import org.apache.commons.logging.Log;
    33  import org.apache.commons.logging.LogFactory;
    34
    35  /***
    36   * A simple implementation of the {@link java.util.Map} interface to handle a collection of portlet session
    37   * attributes. The {@link #entrySet()} method enumerates over all session attributes and creates a Set of entries.
    38   * Note, this will occur lazily - only when the entry set is asked for.
    39   *
    40   */
    41  public class PortletSessionMap extends AbstractMap {
    42
    43      private static final Log LOG = LogFactory.getLog(PortletSessionMap.class);
    44
    45      private PortletSession session = null;
    46      private Set<Object> entries = null;
    47
    48      /***
    49       * Creates a new session map given a portlet request.
    50       *
    51       * @param request the portlet request object.
    52       */
    53      public PortletSessionMap(PortletRequest request) {
    54          this.session = request.getPortletSession();
    55          if(LOG.isDebugEnabled()) {
    56              LOG.debug("Dumping session info: ");
    57              Enumeration enumeration = session.getAttributeNames();
    58              while(enumeration.hasMoreElements()) {
    59                  String key = (String)enumeration.nextElement();
    60                  Object val = session.getAttribute(key);
    61                  LOG.debug(key + " = " + val);
    62              }
    63          }
    64      }
    65
    66      /***
    67       * @see java.util.Map#entrySet()
    68       */
    69      public Set entrySet() {
    70          synchronized (session) {
    71              if (entries == null) {
    72                  entries = new HashSet<Object>();
    73
    74                  Enumeration enumeration = session.getAttributeNames();
    75
    76                  while (enumeration.hasMoreElements()) {
    77                      final String key = enumeration.nextElement().toString();
    78                      final Object value = session.getAttribute(key);
    79                      entries.add(new Map.Entry() {
    80                          public boolean equals(Object obj) {
    81                              Map.Entry entry = (Map.Entry) obj;
    82
    83                              return ((key == null) ? (entry.getKey() == null)
    84                                      : key.equals(entry.getKey()))
    85                                      && ((value == null) ? (entry.getValue() == null)
    86                                              : value.equals(entry.getValue()));
    87                          }
    88
    89                          public int hashCode() {
    90                              return ((key == null) ? 0 : key.hashCode())
    91                                      ^ ((value == null) ? 0 : value.hashCode());
    92                          }
    93
    94                          public Object getKey() {
    95                              return key;
    96                          }
    97
    98                          public Object getValue() {
    99                              return value;
    100                         }
    101
    102                         public Object setValue(Object obj) {
    103                             session.setAttribute(key, obj);
    104
    105                             return value;
    106                         }
    107                     });
    108                 }
    109             }
    110         }
    111
    112         return entries;
    113     }
    114
    115     /***
    116      * Returns the session attribute associated with the given key or
    117      * <tt>null</tt> if it doesn't exist.
    118      *
    119      * @param key the name of the session attribute.
    120      * @return the session attribute or <tt>null</tt> if it doesn't exist.
    121      */
    122     public Object get(Object key) {
    123         synchronized (session) {
    124             return session.getAttribute(key.toString());
    125         }
    126     }
    127
    128     /***
    129      * Saves an attribute in the session.
    130      *
    131      * @param key the name of the session attribute.
    132      * @param value the value to set.
    133      * @return the object that was just set.
    134      */
    135     public Object put(Object key, Object value) {
    136         synchronized (session) {
    137             entries = null;
    138             session.setAttribute(key.toString(), value);
    139
    140             return get(key);
    141         }
    142     }
    143
    144     /***
    145      * @see java.util.Map#clear()
    146      */
    147     public void clear() {
    148         synchronized (session) {
    149             entries = null;
    150             session.invalidate();
    151         }
    152     }
    153
    154     /***
    155      * Removes the specified session attribute.
    156      *
    157      * @param key the name of the attribute to remove.
    158      * @return the value that was removed or <tt>null</tt> if the value was
    159      * not found (and hence, not removed).
    160      */
    161     public Object remove(Object key) {
    162         synchronized (session) {
    163             entries = null;
    164
    165             Object value = get(key);
    166             session.removeAttribute(key.toString());
    167
    168             return value;
    169         }
    170     }
    171 }