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1   /*
2    * $Id: File.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.commons.logging.Log;
27  import org.apache.commons.logging.LogFactory;
28  import org.apache.struts2.views.annotations.StrutsTag;
29  import org.apache.struts2.views.annotations.StrutsTagAttribute;
30  
31  import com.opensymphony.xwork2.util.ValueStack;
32  
33  /***
34   * <!-- START SNIPPET: javadoc -->
35   * Renders an HTML file input element.
36   * <!-- END SNIPPET: javadoc -->
37   *
38   * <p/> <b>Examples</b>
39   *
40   * <pre>
41   * <!-- START SNIPPET: example -->
42   * &lt;s:file name="anUploadFile" accept="text/*" /&gt;
43   * &lt;s:file name="anohterUploadFIle" accept="text/html,text/plain" /&gt;
44   * <!-- END SNIPPET: example -->
45   * </pre>
46   *
47   */
48  @StrutsTag(name="file", tldTagClass="org.apache.struts2.views.jsp.ui.FileTag", description="Render a file input field")
49  public class File extends UIBean {
50      private final static Log log = LogFactory.getLog(File.class);
51  
52      final public static String TEMPLATE = "file";
53  
54      protected String accept;
55      protected String size;
56  
57      public File(ValueStack stack, HttpServletRequest request, HttpServletResponse response) {
58          super(stack, request, response);
59      }
60  
61      protected String getDefaultTemplate() {
62          return TEMPLATE;
63      }
64  
65      public void evaluateParams() {
66          super.evaluateParams();
67  
68          Form form = (Form) findAncestor(Form.class);
69          if (form != null) {
70              String encType = (String) form.getParameters().get("enctype");
71              if (!"multipart/form-data".equals(encType)) {
72                  // uh oh, this isn't good! Let's warn the developer
73                  log.warn("Struts has detected a file upload UI tag (s:file) being used without a form set to enctype 'multipart/form-data'. This is probably an error!");
74              }
75  
76              String method = (String) form.getParameters().get("method");
77              if (!"post".equalsIgnoreCase(method)) {
78                  // uh oh, this isn't good! Let's warn the developer
79                  log.warn("Struts has detected a file upload UI tag (s:file) being used without a form set to method 'POST'. This is probably an error!");
80              }
81          }
82  
83          if (accept != null) {
84              addParameter("accept", findString(accept));
85          }
86  
87          if (size != null) {
88              addParameter("size", findString(size));
89          }
90      }
91  
92      @StrutsTagAttribute(description="HTML accept attribute to indicate accepted file mimetypes")
93      public void setAccept(String accept) {
94          this.accept = accept;
95      }
96  
97      @StrutsTagAttribute(description="HTML size attribute", required=false, type="Integer")
98      public void setSize(String size) {
99          this.size = size;
100     }
101 }