Upload and POST file to PHP page with Java

Even though the thread is very old, there may still be someone around looking for a more easy way to solve this problem (like me :))

After some research I found a way to uplaod a file without changing the original poster's Java-Code. You just have to use the following PHP-code:

<?php
  $filename="abc.xyz";
  $fileData=file_get_contents('php://input');
  $fhandle=fopen($filename, 'wb');
  fwrite($fhandle, $fileData);
  fclose($fhandle);
  echo("Done uploading");
?>

This code is just fetching the raw data sent by the java-application and writing it into a file. There is, however one problem: You dont get the original filename, so you have to transmit it somehow else.

I solved this problem by using a GET-Parameter, which makes a little change in the Java-code necessary:

HttpURLConnection httpUrlConnection = (HttpURLConnection)new URL("http://www.mypage.org/upload.php").openConnection();

changes to

HttpURLConnection httpUrlConnection = (HttpURLConnection)new URL("http://www.mypage.org/upload.php?filename=abc.def").openConnection();

In your PHP-script you change the line

$filename="abc.xyz";

to

$filename=$_GET['filename'];

This solution doesn't use any external librarys and seems to me much more simple than some of the other posted ones...

Hope I could help anyone:)


This is an old thread, but for the benefit of others, here is a fully working example of exactly what the op asks for:

PHP server code:

<?php 

$target_path = "uploads/"; 

$target_path = $target_path . basename( $_FILES['uploadedfile']['name']); 

if(move_uploaded_file($_FILES['uploadedfile']['tmp_name'], $target_path)) { 
    echo "The file ". basename( $_FILES['uploadedfile']['name'])." has been uploaded"; 
} else{ 
    echo "There was an error uploading the file, please try again!"; 
}

?> 

Java client code:

import java.io.OutputStream;
import java.io.InputStream;
import java.net.URLConnection;
import java.net.URL;
import java.net.Socket;

public class Main {
    private final String CrLf = "\r\n";

    public static void main(String[] args) {
        Main main = new Main();
        main.httpConn();
    }

    private void httpConn() {
        URLConnection conn = null;
        OutputStream os = null;
        InputStream is = null;

        try {
            URL url = new URL("http://localhost/test/post.php");
            System.out.println("url:" + url);
            conn = url.openConnection();
            conn.setDoOutput(true);

            String postData = "";

            InputStream imgIs = getClass().getResourceAsStream("/test.jpg");
            byte[] imgData = new byte[imgIs.available()];
            imgIs.read(imgData);

            String message1 = "";
            message1 += "-----------------------------4664151417711" + CrLf;
            message1 += "Content-Disposition: form-data; name=\"uploadedfile\"; filename=\"test.jpg\""
                    + CrLf;
            message1 += "Content-Type: image/jpeg" + CrLf;
            message1 += CrLf;

            // the image is sent between the messages in the multipart message.

            String message2 = "";
            message2 += CrLf + "-----------------------------4664151417711--"
                    + CrLf;

            conn.setRequestProperty("Content-Type",
                    "multipart/form-data; boundary=---------------------------4664151417711");
            // might not need to specify the content-length when sending chunked
            // data.
            conn.setRequestProperty("Content-Length", String.valueOf((message1
                    .length() + message2.length() + imgData.length)));

            System.out.println("open os");
            os = conn.getOutputStream();

            System.out.println(message1);
            os.write(message1.getBytes());

            // SEND THE IMAGE
            int index = 0;
            int size = 1024;
            do {
                System.out.println("write:" + index);
                if ((index + size) > imgData.length) {
                    size = imgData.length - index;
                }
                os.write(imgData, index, size);
                index += size;
            } while (index < imgData.length);
            System.out.println("written:" + index);

            System.out.println(message2);
            os.write(message2.getBytes());
            os.flush();

            System.out.println("open is");
            is = conn.getInputStream();

            char buff = 512;
            int len;
            byte[] data = new byte[buff];
            do {
                System.out.println("READ");
                len = is.read(data);

                if (len > 0) {
                    System.out.println(new String(data, 0, len));
                }
            } while (len > 0);

            System.out.println("DONE");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            System.out.println("Close connection");
            try {
                os.close();
            } catch (Exception e) {
            }
            try {
                is.close();
            } catch (Exception e) {
            }
            try {

            } catch (Exception e) {
            }
        }
    }
}

you can figure out how to adapt it for your site, but I have tested the above code and it works. I can't take credit for it though >> See Original Post


You need to use a form-multipart encoded post for PHP to be able to read it the way you are attempting. This website outlines a good way to do it and has links to libraries that can help you out.


All above answers are 100% correct. You can also use plain sockets, in which case your method would look like this:

        // Compose the request header
        StringBuffer buf = new StringBuffer();
        buf.append("POST ");
        buf.append(uploader.getUploadAction());
        buf.append(" HTTP/1.1\r\n");
        buf.append("Content-Type: multipart/form-data; boundary=");
        buf.append(boundary);
        buf.append("\r\n");
        buf.append("Host: ");
        buf.append(uploader.getUploadHost());
        buf.append(':');
        buf.append(uploader.getUploadPort());
        buf.append("\r\n");
        buf.append("Connection: close\r\n");
        buf.append("Cache-Control: no-cache\r\n");

        // Add cookies
        List cookies = uploader.getCookies();
        if (!cookies.isEmpty())
            {
                buf.append("Cookie: ");
                for (Iterator iterator = cookies.iterator(); iterator.hasNext(); )
                    {
                        Parameter parameter = (Parameter)iterator.next();

                        buf.append(parameter.getName());
                        buf.append('=');
                        buf.append(parameter.getValue());

                        if (iterator.hasNext())
                            buf.append("; ");
                    }

                buf.append("\r\n");
            }

        buf.append("Content-Length: ");

        // Request body
        StringBuffer body = new StringBuffer();
        List fields = uploader.getFields();
        for (Iterator iterator = fields.iterator(); iterator.hasNext();)
            {

                Parameter parameter = (Parameter) iterator.next();

                body.append("--");
                body.append(boundary);
                body.append("\r\n");
                body.append("Content-Disposition: form-data; name=\"");
                body.append(parameter.getName());
                body.append("\"\r\n\r\n");
                body.append(parameter.getValue());
                body.append("\r\n");
            }

        body.append("--");
        body.append(boundary);
        body.append("\r\n");
        body.append("Content-Disposition: form-data; name=\"");
        body.append(uploader.getImageFieldName());
        body.append("\"; filename=\"");
        body.append(file.getName());
        body.append("\"\r\n");
        body.append("Content-Type: image/pjpeg\r\n\r\n");

        String boundary = "WHATEVERYOURDEARHEARTDESIRES";
        String lastBoundary = "\r\n--" + boundary + "--\r\n";
        long length = file.length() + (long) lastBoundary.length() + (long) body.length();
        long total = buf.length() + body.length();

        buf.append(length);
        buf.append("\r\n\r\n");

        // Upload here
        InetAddress address = InetAddress.getByName(uploader.getUploadHost());
        Socket socket = new Socket(address, uploader.getUploadPort());
        try
            {
                socket.setSoTimeout(60 * 1000);
                uploadStarted(length);

                PrintStream out = new PrintStream(new BufferedOutputStream(socket.getOutputStream()));
                out.print(buf);
                out.print(body);

                // Send the file
                byte[] bytes = new byte[1024 * 65];
                int size;
                InputStream in = new BufferedInputStream(new FileInputStream(file));
                try
                    {
                        while ((size = in.read(bytes)) > 0)
                            {
                                total += size;
                                out.write(bytes, 0, size);
                                transferred(total);
                            }
                    }
                finally
                    {
                        in.close();
                    }

                out.print(lastBoundary);
                out.flush();

                // Read the response
                BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                while (reader.readLine() != null);
            }
        finally
            {
                socket.close();
            }