JSF文件上传

JSF2.0虽然添加了很多新特性，但是还是没有官方的对上传的支持。直接使用

<h:form enctype="multipart/form-data" >

</h:form>

是不行的。因为multipart/form-data类型的request是解析不了的。

解决方法可以使用filter对request进行包装（原request似乎是不能更改的，所以借助包装），在解析request是可以借助apache的commons-fileupload组件。

Myfaces刚好给出了这个解决方案的实现：

MultipartFilter+MultipartRequestWrapper(Use commons-fileupload).

 

原来是打包在一个myfaces-extensions.jar中，现在找不到官方的下载，不过在Tomahawk包里可以找到(org.apache.myfaces.webapp.filter.*，MultipartFilter似乎都弄到ExtensionsFilter里了)。

 

个人觉得旧版的源代码挺参考价值的，贴出来分享下。

 MultipartRequestWrapper：

 

1 /*
2  * Copyright 2004 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package org.apache.myfaces.component.html.util;
17
18 import org.apache.commons.fileupload.*;
19 import org.apache.commons.logging.Log;
20 import org.apache.commons.logging.LogFactory;
21
22 import javax.servlet.http.HttpServletRequest ;
23 import javax.servlet.http.HttpServletRequestWrapper ;
24 import java.io.UnsupportedEncodingException ;
25 import java.util.*;
26
27 /**
28  * @author Sylvain Vieujot (latest modification by $Author: svieujot $)
29  * @version $Revision: 1.2 $ $Date: 2004/12/11 21:41:33 $
30  * $Log: MultipartRequestWrapper.java,v $
31  * Revision 1.2 2004/12/11 21:41:33 svieujot
32  * Add method to get the FileItems.
33  *
34  * Revision 1.1 2004/12/01 16:32:03 svieujot
35  * Convert the Multipart filter in an ExtensionsFilter that provides an additional facility to include resources in a page.
36  * Tested only with javascript resources right now, but should work fine with images too.
37  * Some work to do to include css resources.
38  * The popup component has been converted to use this new Filter.
39  *
40  * Revision 1.8 2004/11/16 16:25:52 mmarinschek
41  * new popup - component; not yet finished
42  *
43  * Revision 1.7 2004/10/13 11:50:57 matze
44  * renamed packages to org.apache
45  *
46  * Revision 1.6 2004/09/09 13:43:59 manolito
47  * query string parameters where missing in the parameter map
48  *
49  * Revision 1.5 2004/08/16 18:06:47 svieujot
50  * Another bug fix for bug #1001511. Patch submitted by Takashi Okamoto.
51  *
52  * Revision 1.4 2004/08/02 04:26:06 svieujot
53  * Fix for bug #1001511 : setHeaderEncoding
54  *
55  */
56 public class MultipartRequestWrapper
57         extends HttpServletRequestWrapper
58 {
59     private static Log log = LogFactory.getLog(MultipartRequestWrapper.class);
60
61     HttpServletRequest  request = null;
62     HashMap parametersMap = null;
63     DiskFileUpload fileUpload = null;
64     HashMap fileItems = null;
65     int maxSize;
66     int thresholdSize;
67     String  repositoryPath;
68
69     public MultipartRequestWrapper(HttpServletRequest  request,
70                                    int maxSize, int thresholdSize,
71                                    String  repositoryPath){
72         super( request );
73         this.request = request;
74         this.maxSize = maxSize;
75         this.thresholdSize = thresholdSize;
76         this.repositoryPath = repositoryPath;
77     }
78
79     private void parseRequest() {
80         fileUpload = new DiskFileUpload();
81         fileUpload.setFileItemFactory(new DefaultFileItemFactory());
82         fileUpload.setSizeMax(maxSize);
83
84         fileUpload.setSizeThreshold(thresholdSize);
85
86         if(repositoryPath != null && repositoryPath.trim().length()>0)
87             fileUpload.setRepositoryPath(repositoryPath);
88
89         String  charset = request.getCharacterEncoding();
90         fileUpload.setHeaderEncoding(charset);
91
92
93         List requestParameters = null;
94         try{
95             requestParameters = fileUpload.parseRequest(request);
96         } catch (FileUploadBase.SizeLimitExceededException e) {
97
98             // TODO: find a way to notify the user about the fact that the uploaded file exceeded size limit
99
100             if(log.isInfoEnabled())
101                 log.info("user tried to upload a file that exceeded file-size limitations.",e);
102
103             requestParameters = Collections.EMPTY_LIST;
104
105         }catch(FileUploadException fue){
106             log.error("Exception while uploading file.", fue);
107             requestParameters = Collections.EMPTY_LIST;
108         }
109
110         parametersMap = new HashMap( requestParameters.size() );
111         fileItems = new HashMap();
112
113         for (Iterator iter = requestParameters.iterator(); iter.hasNext(); ){
114             FileItem fileItem = (FileItem) iter.next();
115
116             if (fileItem.isFormField()) {
117                 String  name = fileItem.getFieldName();
118
119                 // The following code avoids commons-fileupload charset problem.
120 // After fixing commons-fileupload, this code should be
121 //
122 // String value = fileItem.getString();
123 //
124 String  value = null;
125                 if ( charset == null) {
126                     value = fileItem.getString();
127                 } else {
128                     try {
129                         value = new String (fileItem.get(), charset);
130                     } catch (UnsupportedEncodingException  e){
131                         value = fileItem.getString();
132                     }
133                 }
134
135                 addTextParameter(name, value);
136             } else { // fileItem is a File
137 if (fileItem.getName() != null) {
138                     fileItems.put(fileItem.getFieldName(), fileItem);
139                 }
140             }
141         }
142
143         //Add the query string paramters
144 for (Iterator it = request.getParameterMap().entrySet().iterator(); it.hasNext(); )
145         {
146             Map.Entry entry = (Map.Entry)it.next();
147             String [] valuesArray = (String [])entry.getValue();
148             for (int i = 0; i < valuesArray.length; i++)
149             {
150                 addTextParameter((String )entry.getKey(), valuesArray[i]);
151             }
152         }
153     }
154
155     private void addTextParameter(String  name, String  value){
156         if( ! parametersMap.containsKey( name ) ){
157             String [] valuesArray = {value};
158             parametersMap.put(name, valuesArray);
159         }else{
160             String [] storedValues = (String [])parametersMap.get( name );
161             int lengthSrc = storedValues.length;
162             String [] valuesArray = new String [lengthSrc+1];
163             System.arraycopy(storedValues, 0, valuesArray, 0, lengthSrc);
164             valuesArray[lengthSrc] = value;
165             parametersMap.put(name, valuesArray);
166         }
167     }
168
169     public Enumeration getParameterNames() {
170         if( parametersMap == null ) parseRequest();
171
172         return Collections.enumeration( parametersMap.keySet() );
173     }
174
175     public String  getParameter(String  name) {
176         if( parametersMap == null ) parseRequest();
177
178         String [] values = (String [])parametersMap.get( name );
179         if( values == null )
180             return null;
181         return values[0];
182     }
183
184     public String [] getParameterValues(String  name) {
185         if( parametersMap == null ) parseRequest();
186
187         return (String [])parametersMap.get( name );
188     }
189
190     public Map getParameterMap() {
191         if( parametersMap == null ) parseRequest();
192
193         return parametersMap;
194     }
195
196     // Hook for the x:inputFileUpload tag.
197 public FileItem getFileItem(String  fieldName) {
198         if( fileItems == null ) parseRequest();
199
200         return (FileItem) fileItems.get( fieldName );
201     }
202
203     /**
204      * Not used internaly by MyFaces, but provides a way to handle the uploaded files
205      * out of MyFaces.
206      */
207     public Map getFileItems(){
208         return fileItems;
209     }
210 }

 

 MultipartFilter：

 

1 /*
2  * Copyright 2005 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package org.apache.myfaces.component.html.util;
17
18 import java.io.IOException ;
19
20 import javax.servlet.Filter ;
21 import javax.servlet.FilterChain ;
22 import javax.servlet.FilterConfig ;
23 import javax.servlet.ServletException ;
24 import javax.servlet.ServletRequest ;
25 import javax.servlet.ServletResponse ;
26 import javax.servlet.http.HttpServletRequest ;
27 import javax.servlet.http.HttpServletResponse ;
28
29 import org.apache.commons.fileupload.FileUpload;
30
31
32 /**
33  * This filters is mandatory for the use of many components.
34  * It handles the Multipart requests (for file upload)
35  * It's used by the components that need javascript libraries
36  *
37  * @author Sylvain Vieujot (latest modification by $Author: oros $)
38  * @author <a HREF="mailto:[e-mail]" mce_HREF="mailto:[e-mail]">Oliver Rossmueller </a>
39  * @version $Revision: 1.1 $ $Date: 2005/03/20 23:16:08 $
40  */
41 public class MultipartFilter implements Filter
42 {
43
44     private int uploadMaxFileSize = 100 * 1024 * 1024; // 10 MB
45
46     private int uploadThresholdSize = 1 * 1024 * 1024; // 1 MB
47
48     private String  uploadRepositoryPath = null; //standard temp directory
49
50
51     public void init(FilterConfig  filterConfig)
52     {
53         uploadMaxFileSize = resolveSize(filterConfig.getInitParameter("uploadMaxFileSize"), uploadMaxFileSize);
54         uploadThresholdSize = resolveSize(filterConfig.getInitParameter("uploadThresholdSize"), uploadThresholdSize);
55         uploadRepositoryPath = filterConfig.getInitParameter("uploadRepositoryPath");
56     }
57
58
59     private int resolveSize(String  param, int defaultValue)
60     {
61         int numberParam = defaultValue;
62
63         if (param != null)
64         {
65             param = param.toLowerCase();
66             int factor = 1;
67             String  number = param;
68
69             if (param.endsWith("g"))
70             {
71                 factor = 1024 * 1024 * 1024;
72                 number = param.substring(0, param.length() - 1);
73             } else if (param.endsWith("m"))
74             {
75                 factor = 1024 * 1024;
76                 number = param.substring(0, param.length() - 1);
77             } else if (param.endsWith("k"))
78             {
79                 factor = 1024;
80                 number = param.substring(0, param.length() - 1);
81             }
82
83             numberParam = Integer.parseInt(number) * factor;
84         }
85         return numberParam;
86     }
87
88
89     public void doFilter(ServletRequest  request, ServletResponse  response, FilterChain  chain) throws IOException , ServletException
90     {
91         if (!(response instanceof HttpServletResponse ))
92         {
93             chain.doFilter(request, response);
94             return;
95         }
96
97         HttpServletRequest  httpRequest = (HttpServletRequest ) request;
98
99         // For multipart/form-data requests
100 if (FileUpload.isMultipartContent(httpRequest))
101         {
102             chain.doFilter(new MultipartRequestWrapper(httpRequest, uploadMaxFileSize, uploadThresholdSize, uploadRepositoryPath), response);
103         } else
104         {
105             chain.doFilter(request, response);
106         }
107     }
108
109
110     public void destroy()
111     {
112         // NoOp
113 }
114 }