jsf文件上傳

JSF2.0雖然添加了很多新特性，但是還是沒有官方的對上傳的支持。直接使用

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

</h:form>

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

解決方法可以使用filter對request進行包裝（原request似乎是不能更改的，所以藉助包裝），在解析request是可以藉助apache的commons-fileupload組件。

Myfaces剛好給出了這個解決方案的實現：

MultipartFilter+MultipartRequestWrapper(Use commons-fileupload).

 

原來是打包在一個myfaces-extensions.jar中，現在找不到官方的下載，不過在Tomahawk包裏可以找到(org.apache.myfaces.webapp.filter.*，MultipartFilter似乎都弄到ExtensionsFilter裏了)。

 

個人覺得舊版的源代碼挺參考價值的，貼出來分享下。

 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 }