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1   /*
2    * $Id: File.java 651946 2008-04-27 13:41:38Z apetrelli $
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.struts2.components;
23  
24  import javax.servlet.http.HttpServletRequest;
25  import javax.servlet.http.HttpServletResponse;
26  
27  import org.apache.struts2.views.annotations.StrutsTag;
28  import org.apache.struts2.views.annotations.StrutsTagAttribute;
29  
30  import com.opensymphony.xwork2.util.ValueStack;
31  import com.opensymphony.xwork2.util.logging.Logger;
32  import com.opensymphony.xwork2.util.logging.LoggerFactory;
33  
34  /***
35   * <!-- START SNIPPET: javadoc -->
36   * Renders an HTML file input element.
37   * <!-- END SNIPPET: javadoc -->
38   *
39   * <p/> <b>Examples</b>
40   *
41   * <pre>
42   * <!-- START SNIPPET: example -->
43   * &lt;s:file name="anUploadFile" accept="text/*" /&gt;
44   * &lt;s:file name="anohterUploadFIle" accept="text/html,text/plain" /&gt;
45   * <!-- END SNIPPET: example -->
46   * </pre>
47   *
48   */
49  @StrutsTag(
50      name="file",
51      tldTagClass="org.apache.struts2.views.jsp.ui.FileTag",
52      description="Render a file input field",
53      allowDynamicAttributes=true)
54  public class File extends UIBean {
55      private final static Logger LOG = LoggerFactory.getLogger(File.class);
56  
57      final public static String TEMPLATE = "file";
58  
59      protected String accept;
60      protected String size;
61  
62      public File(ValueStack stack, HttpServletRequest request, HttpServletResponse response) {
63          super(stack, request, response);
64      }
65  
66      protected String getDefaultTemplate() {
67          return TEMPLATE;
68      }
69  
70      public void evaluateParams() {
71          super.evaluateParams();
72  
73          Form form = (Form) findAncestor(Form.class);
74          if (form != null) {
75              String encType = (String) form.getParameters().get("enctype");
76              if (!"multipart/form-data".equals(encType)) {
77                  // uh oh, this isn't good! Let's warn the developer
78                  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!");
79              }
80  
81              String method = (String) form.getParameters().get("method");
82              if (!"post".equalsIgnoreCase(method)) {
83                  // uh oh, this isn't good! Let's warn the developer
84                  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!");
85              }
86          }
87  
88          if (accept != null) {
89              addParameter("accept", findString(accept));
90          }
91  
92          if (size != null) {
93              addParameter("size", findString(size));
94          }
95      }
96  
97      @StrutsTagAttribute(description="HTML accept attribute to indicate accepted file mimetypes")
98      public void setAccept(String accept) {
99          this.accept = accept;
100     }
101 
102     @StrutsTagAttribute(description="HTML size attribute", required=false, type="Integer")
103     public void setSize(String size) {
104         this.size = size;
105     }
106 }