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    1   /*
    2    * $Id: ElseIf.java 497654 2007-01-19 00:21:57Z rgielen $
    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.components;
    22
    23  import java.io.Writer;
    24
    25  import org.apache.struts2.views.annotations.StrutsTag;
    26  import org.apache.struts2.views.annotations.StrutsTagAttribute;
    27
    28  import com.opensymphony.xwork2.util.ValueStack;
    29
    30  /***
    31   * <!-- START SNIPPET: javadoc -->
    32   *
    33   * <p>Perform basic condition flow. 'If' tag could be used by itself or with 'Else If' Tag and/or single/multiple 'Else'
    34   * Tag.</p>
    35   *
    36   * <!-- END SNIPPET: javadoc -->
    37   *
    38   *
    39   * <!-- START SNIPPET: params -->
    40   *
    41   * <ul>
    42   *
    43   * <li>test* (Boolean) - Logic to determined if body of tag is to be displayed</li>
    44   *
    45   * </ul>
    46   *
    47   * <!-- END SNIPPET: params -->
    48   *
    49   *
    50   * <pre>
    51   * <!-- START SNIPPET: example -->
    52   *  &lt;s:if test="%{false}"&gt;
    53   *      &lt;div&gt;Will Not Be Executed&lt;/div&gt;
    54   *  &lt;/s:if&gt;
    55   *  &lt;s:elseif test="%{true}"&gt;
    56   *      &lt;div&gt;Will Be Executed&lt;/div&gt;
    57   *  &lt;/s:elseif&gt;
    58   *  &lt;s:else&gt;
    59   *      &lt;div&gt;Will Not Be Executed&lt;/div&gt;
    60   *  &lt;/s:else&gt;
    61   * <!-- END SNIPPET: example -->
    62   * </pre>
    63   *
    64   */
    65  @StrutsTag(name="elseif", tldTagClass="org.apache.struts2.views.jsp.ElseIfTag", description="Elseif tag")
    66  public class ElseIf extends Component {
    67      public ElseIf(ValueStack stack) {
    68          super(stack);
    69      }
    70
    71      protected Boolean answer;
    72      protected String test;
    73
    74      public boolean start(Writer writer) {
    75          Boolean ifResult = (Boolean) stack.getContext().get(If.ANSWER);
    76
    77          if ((ifResult == null) || (ifResult.booleanValue())) {
    78              return false;
    79          }
    80
    81          //make the comparision
    82          answer = (Boolean) findValue(test, Boolean.class);
    83
    84          if (answer == null) {
    85              answer = Boolean.FALSE;
    86          }
    87          if (answer.booleanValue()) {
    88              stack.getContext().put(If.ANSWER, answer);
    89          }
    90          return answer != null && answer.booleanValue();
    91      }
    92
    93      public boolean end(Writer writer, String body) {
    94          if (answer == null) {
    95              answer = Boolean.FALSE;
    96          }
    97          if (answer.booleanValue()) {
    98              stack.getContext().put(If.ANSWER, answer);
    99          }
    100         return super.end(writer, "");
    101     }
    102
    103     @StrutsTagAttribute(description="Expression to determine if body of tag is to be displayed", type="Boolean", required=true)
    104     public void setTest(String test) {
    105         this.test = test;
    106     }
    107 }