commons fileUpload: specifying an upload directory within Webapplication context

Question

I'd like to know how to specify an upload directory preferably a relative path to a directory under my WEB-CONTENT directory where I'd like to store uploaded files: I get an error when I specify the upload be store as:

**File saveFile = new File("/"+fileName);** please refer to code below

Error:

INFO: Server startup in 497 ms
java.io.IOException: The system cannot find the path specified
 at java.io.WinNTFileSystem.createFileExclusively(Native Method)
 at java.io.File.createNewFile(Unknown Source)
 at controller.UploadServlet.processUploadedFile(UploadServlet.java:86)
 at controller.UploadServlet.doPost(UploadServlet.java:61)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
 at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
 at java.lang.Thread.run(Unknown Source)
java.io.IOException: Access is denied
 at java.io.WinNTFileSystem.createFileExclusively(Native Method)
 at java.io.File.createNewFile(Unknown Source)
 at controller.UploadServlet.processUploadedFile(UploadServlet.java:86)
 at controller.UploadServlet.doPost(UploadServlet.java:61)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
 at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
 at java.lang.Thread.run(Unknown Source)

my code:

**
 * Instantiates SempediaHome Controller
 */
public class UploadServlet extends HttpServlet {

 /**
  * 
  * @param
  * @return
  */
 public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException {

  // Create a factory for disk-based file items
  DiskFileItemFactory factory = new DiskFileItemFactory();

  // Set factory constraints
  //factory.setSizeThreshold(yourMaxMemorySize);
  factory.setRepository(new File("/tmp"));

  // Create a new file upload handler
  ServletFileUpload upload = new ServletFileUpload(factory);

  // Set overall request size constraint
  //upload.setSizeMax(yourMaxRequestSize);

  // Parse the request
  try {
   List /* FileItem */ items = upload.parseRequest(request);
   Iterator iter = items.iterator();
   while (iter.hasNext()) {
       FileItem item = (FileItem) iter.next();

       if (item.isFormField()) {
           this.processFormField(item);
       } else {
           this.processUploadedFile(item);
       }
   }
  } catch (FileUploadException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }

 /**
  * 
  * @param
  * @return
  */
 public void processUploadedFile(FileItem item) throws IOException {

  // Process a file upload
  if (!item.isFormField()) {
      //String fieldName = item.getFieldName();
      String fileName = item.getName();
      //String contentType = item.getContentType();
      //boolean isInMemory = item.isInMemory();
      //long sizeInBytes = item.getSize();     
      try {
       File saveFile = new File("/"+fileName);
       saveFile.createNewFile();
    item.write(saveFile);
   } catch (Exception e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
 }

 /**
  * 
  * @param
  * @return
  */
 public void processFormField(FileItem item) {

 }

}

Answer 1

In your servlet (or jsp):

String contextRoot = getServletContext().getRealPath("/")

returns the context root. So:

factory.setRepository(new File(contextRoot + "WEB-INF/tmp"));

(you'd better not put the tmp directory in a place accessible from the web)

Your exception means that your current OS user doesn't have permissions to write to the target directory. Make sure it was write permissions for the desired directory.