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1   /*
2    * $Id: Select.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 javax.servlet.http.HttpServletRequest;
24  import javax.servlet.http.HttpServletResponse;
25  
26  import org.apache.struts2.views.annotations.StrutsTag;
27  import org.apache.struts2.views.annotations.StrutsTagAttribute;
28  
29  import com.opensymphony.xwork2.util.ValueStack;
30  
31  /***
32   * <!-- START SNIPPET: javadoc -->
33   *
34   * Render an HTML input tag of type select.
35   *
36   * <!-- END SNIPPET: javadoc -->
37   *
38   * <p/> <b>Examples</b>
39   * <pre>
40   * <!-- START SNIPPET: example -->
41   *
42   * &lt;s:select label="Pets"
43   *        name="petIds"
44   *        list="petDao.pets"
45   *        listKey="id"
46   *        listValue="name"
47   *        multiple="true"
48   *        size="3"
49   *        required="true"
50   * /&gt;
51   *
52   * &lt;s:select label="Months"
53   *        name="months"
54   *        headerKey="-1" headerValue="Select Month"
55   *        list="#{'01':'Jan', '02':'Feb', [...]}"
56   *        value="selectedMonth"
57   *        required="true"
58   * /&gt;
59   *
60   * // The month id (01, 02, ...) returned by the getSelectedMonth() call
61   * // against the stack will be auto-selected
62   *
63   * <!-- END SNIPPET: example -->
64   * </pre>
65   *
66   * <p/>
67   *
68   * <!-- START SNIPPET: exnote -->
69   *
70   * Note: For any of the tags that use lists (select probably being the most ubiquitous), which uses the OGNL list
71   * notation (see the "months" example above), it should be noted that the map key created (in the months example,
72   * the '01', '02', etc.) is typed. '1' is a char, '01' is a String, "1" is a String. This is important since if
73   * the value returned by your "value" attribute is NOT the same type as the key in the "list" attribute, they
74   * WILL NOT MATCH, even though their String values may be equivalent. If they don't match, nothing in your list
75   * will be auto-selected.<p/>
76   *
77   * <!-- END SNIPPET: exnote -->
78   *
79   */
80  @StrutsTag(name="select", tldTagClass="org.apache.struts2.views.jsp.ui.SelectTag", description="Render a select element")
81  public class Select extends ListUIBean {
82      final public static String TEMPLATE = "select";
83  
84      protected String emptyOption;
85      protected String headerKey;
86      protected String headerValue;
87      protected String multiple;
88      protected String size;
89  
90      public Select(ValueStack stack, HttpServletRequest request, HttpServletResponse response) {
91          super(stack, request, response);
92      }
93  
94      protected String getDefaultTemplate() {
95          return TEMPLATE;
96      }
97  
98      public void evaluateExtraParams() {
99          super.evaluateExtraParams();
100 
101         if (emptyOption != null) {
102             addParameter("emptyOption", findValue(emptyOption, Boolean.class));
103         }
104 
105         if (multiple != null) {
106             addParameter("multiple", findValue(multiple, Boolean.class));
107         }
108 
109         if (size != null) {
110             addParameter("size", findString(size));
111         }
112 
113         if ((headerKey != null) && (headerValue != null)) {
114             addParameter("headerKey", findString(headerKey));
115             addParameter("headerValue", findString(headerValue));
116         }
117     }
118 
119     @StrutsTagAttribute(description="Whether or not to add an empty (--) option after the header option", type="Boolean", defaultValue="false")
120     public void setEmptyOption(String emptyOption) {
121         this.emptyOption = emptyOption;
122     }
123 
124     @StrutsTagAttribute(description=" Key for first item in list. Must not be empty! '-1' and '' is correct, '' is bad.")
125     public void setHeaderKey(String headerKey) {
126         this.headerKey = headerKey;
127     }
128 
129     @StrutsTagAttribute(description="Value expression for first item in list")
130     public void setHeaderValue(String headerValue) {
131         this.headerValue = headerValue;
132     }
133 
134     @StrutsTagAttribute(description=" Creates a multiple select. The tag will pre-select multiple values" +
135                 " if the values are passed as an Array (of appropriate types) via the value attribute. Passing " +
136                 "a Collection may work too? Haven't tested this.", type="Boolean", defaultValue="false")
137     public void setMultiple(String multiple) {
138         this.multiple = multiple;
139     }
140 
141     @StrutsTagAttribute(description="Size of the element box (# of elements to show)", type="Integer")
142     public void setSize(String size) {
143         this.size = size;
144     }
145 }