3

In the following code:

public static MultipartEntity buildMultiEntity(final SlingHttpServletRequest request) {
        MultipartEntity multipartEntity = null;
                final Map<String, RequestParameter[]> params = request.getRequestParameterMap();
        if(params.containsKey("myfile")) {
            multipartEntity = new MultipartEntity();

            for (final Map.Entry<String, RequestParameter[]> pairs : params.entrySet()) {
                final String key = pairs.getKey();
                final RequestParameter[] parameterArray = pairs.getValue();
                final RequestParameter param = parameterArray[0];
                InputStream inputStream = null;
                try {
                    inputStream = param.getInputStream();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                multipartEntity.addPart(key, new InputStreamBody(inputStream, param.getFileName()));
            }
        }
        return multipartEntity;
    }

I identify if the request has image as follow

if(params.containsKey("myfile"))

How to identify, if the request has image even if I dont know, what is the input name of the image file?

Ronald
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  • This is not exactly answer, but you should NOT do this. Parameters in requests should be all known to you. – libik Jul 21 '15 at 08:57
  • hmm but what if thins changed? – Ronald Jul 21 '15 at 09:00
  • If you cant change it, then you have to do it in "bad way", I understand. However if you are making analysis and you came with this - you did something wrong. – libik Jul 21 '15 at 09:13
  • If you need multiple pictures, the standard is to use array with names : `myfile[0]`, `myfile[1]` ... Then if you use some library or framework (like Spring), you can just have object like this : `MultipartFile[] myfile` and it automatically parse the parameters and add them to that array. – libik Jul 21 '15 at 09:20

1 Answers1

1

I think you can try to use attachment for this purpose. For this you need to add enctype="multipart/form-data" in your form on UI. It will be smth like

<form action="upload" method="post" enctype="multipart/form-data">
    <input type="file" name="file" />
    // some other inputs
</form>

And server side 

@WebServlet("/upload")
@MultipartConfig
public class UploadServlet extends HttpServlet {
    // ...
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    Part filePart = request.getPart("file"); 
    String fileName = filePart.getSubmittedFileName();
    InputStream fileContent = filePart.getInputStream();
    // some job here
}

private static String getFileName(Part part) {
    for (String cd : part.getHeader("content-disposition").split(";")) {
        if (cd.trim().startsWith("filename")) {
            String fileName = cd.substring(cd.indexOf('=') + 1).trim().replace("\"", "");
            return fileName.substring(fileName.lastIndexOf('/') + 1).substring(fileName.lastIndexOf('\\') + 1); // MSIE fix.
        }
    }
    return null;
}
prsmax
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