Accessing uploaded file in Apache Tapestry page

问题

I'm using Apache Tapestry v5.3.7 and I already use the normal Tapestry upload component in a form. For a better user experience I try now to integrate Dropzone.js in a normal Tapestry page without any form. The JavaScript integration works fine. The uploaded file data are transferred to my server with a post request and I can access the request with all of its parameters.

My question is now how can I access the binary data of the uploaded file (maybe as InputStream) to save them in my system? I already injected the http request but getInputStream returns a empty stream.

Thanks for any suggestions

/** Code snippet of page java part */
...

@Inject
protected HttpServletRequest _request;

public void onActivate (String rowId) {
    String fileName=_request.getParameter("file");
    try {
        InputStream is=_request.getInputStream();
        // if I do read from is it returns -1
        // :-(
        doSomeSaveStuff(is); // dummy code
    }
    catch(Exception e) {
        e.printStackTrace();
    }
}

...

回答1:

Taha has a blog post here on his Tapestry Magic blog he integrates a different file uploader library with Tapestry. I'm guessing your answer will be there.

回答2:

Here's one way to do it:

In template:

<t:form t:id="testForm" class="dropzone"> </t:form>

In page.java

  @Inject
  MultipartDecoder multipartDecoder;

  @Component(id = "testForm")
  private Form testForm;

  @Inject
  RequestGlobals requestGlobals;

void onSubmitFromTestForm() throws ManagerException {
    System.out.println("test form invoked");
    HttpServletRequest r = requestGlobals.getHTTPServletRequest();
    UploadedFile u = multipartDecoder.getFileUpload("file");

The uploaded file contains what you uploaded and you can work with it the way you want.

Note: the HttpServletRequest::getParameterMap() , told me that the handle to to the file is called file which is how I know that passing file to getFileUpload makes the decoder correctly parse the multipart/post

来源：https://stackoverflow.com/questions/26015378/accessing-uploaded-file-in-apache-tapestry-page

标签

java

file-upload

tapestry

dropzone.js