First of all, you have to provide a little bit of code to show what you have done, and to know what went wrong. Anyway, I am assuming that you have to upload a file to the server using HTML file upload control.
File upload or to say multipart/form-data encoding type support is not implemented in HttpServlet implementation. So, the request.getParameter() don't work with multipart/form-data. You have to use additional libraries which provide support for this. Apache Commons File Upload is a good example. Their using fileupload guide will help you to get started with the library. Here is a simple example (compiled from using file upload guide).
// Check that we have a file upload request
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (isMultipart) {
// Create a factory for disk-based file items
FileItemFactory factory = new DiskFileItemFactory();
// Create a new file upload handler
ServletFileUpload upload = new ServletFileUpload(factory);
// Parse the request
List /* FileItem */ items = upload.parseRequest(request);
// Process the uploaded items
Iterator iter = items.iterator();
while (iter.hasNext()) {
FileItem item = (FileItem) iter.next();
if (item.isFormField()) {
// Process form field.
String name = item.getFieldName();
String value = item.getString();
} else {
// Process uploaded file.
String fieldName = item.getFieldName();
String fileName = item.getName();
String contentType = item.getContentType();
boolean isInMemory = item.isInMemory();
long sizeInBytes = item.getSize();
if (writeToFile) {
File uploadedFile = new File("path/filename.txt");
item.write(uploadedFile);
}
}
}
} else {
// Normal request. request.getParameter will suffice.
}
