LoadMessagesTag xref

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    1   /*
    2    * $Id: LoadMessagesTag.java 471754 2006-11-06 14:55:09Z 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
    22  package org.apache.struts.faces.taglib;
    23
    24
    25  import java.util.Locale;
    26
    27  import javax.faces.context.FacesContext;
    28
    29  import javax.servlet.jsp.PageContext;
    30  import javax.servlet.jsp.tagext.TagSupport;
    31
    32  import org.apache.struts.Globals;
    33  import org.apache.struts.faces.util.MessagesMap;
    34  import org.apache.struts.util.MessageResources;
    35
    36
    37  /**
    38   * <p>Tag that exposes a specified <code>MessageResources</code> instance
    39   * as <code>Map</code>, so that the embedded messages may be retrieved via
    40   * value binding expressions.</p>
    41   */
    42
    43  public class LoadMessagesTag extends TagSupport {
    44
    45
    46      // ---------------------------------------------------------- Tag Attributes
    47
    48
    49      /**
    50       * <p>The name of the <code>MessageResources</code> to expose, or
    51       * <code>null</code> for the default <code>MessageResources</code>
    52       * for this application module.</p>
    53       */
    54      private String messages = null;
    55      public void setMessages(String messages) {
    56          this.messages = messages;
    57      }
    58
    59
    60      /**
    61       * <p>The request attribute key under which a <code>Map</code>
    62       * will be exposed.</p>
    63       */
    64      private String var = null;
    65      public void setVar(String var) {
    66          this.var = var;
    67      }
    68
    69
    70      // ------------------------------------------------------------- Tag Methods
    71
    72
    73      /**
    74       * <p>Expose a <code>Map</code> wrapping the specified
    75       * <code>MessageResources</code> instance, for the <code>Locale</code>
    76       * specified in the view root component of the current view.</p>
    77       */
    78      public int doStartTag() {
    79
    80          // Acquire the Locale to be wrapped
    81          Locale locale =
    82              FacesContext.getCurrentInstance().getViewRoot().getLocale();
    83
    84          // Acquire the MessageResources to be wrapped
    85          MessageResources messages = null;
    86          if (this.messages == null) {
    87              messages = (MessageResources)
    88                  pageContext.getAttribute(Globals.MESSAGES_KEY,
    89                                           PageContext.REQUEST_SCOPE);
    90              if (messages == null) {
    91                  messages = (MessageResources)
    92                      pageContext.getAttribute(Globals.MESSAGES_KEY,
    93                                               PageContext.APPLICATION_SCOPE);
    94              }
    95          } else {
    96              messages = (MessageResources)
    97                  pageContext.getAttribute(this.messages,
    98                                           PageContext.APPLICATION_SCOPE);
    99          }
    100
    101         // Expose a Map instance under the specified request attribute key
    102         pageContext.setAttribute(var,
    103                                  new MessagesMap(messages, locale),
    104                                  PageContext.REQUEST_SCOPE);
    105
    106         // Skip the body of this tag (if any)
    107         return (SKIP_BODY);
    108
    109     }
    110
    111
    112     /**
    113      * <p>Release any resources allocated by this tag instance.</p>
    114      */
    115     public void release() {
    116
    117         this.messages = null;
    118         this.var = null;
    119
    120     }
    121
    122
    123 }