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How to use post-method with applet and servlet

Jorma Ikonen
Ranch Hand

Joined: Sep 17, 2001
Posts: 49
I'm been trying to solve below problem around one week without success... Please, help me...
The problem is that I should transfer (chipered) data between applet and servlet by using post-method. The applet has code like below and it invokes the doPost-method on servlet, but I'm not able to get any data transferred. See codes below:
URL url = new URL(baseURL, servletName);
HttpURLConnection sc = (HttpURLConnection) url.openConnection();
sc.setRequestProperty ("Content-Type", "application/octet-stream");
sc.setRequestProperty("Content-length", String.valueOf(10));
InputStream in = sc.getInputStream();
OutputStream out = sc.getOutputStream();

doPost-Method in SERVLET:
ServletInputStream in = request.getInputStream();
ServletOutputStream out = response.getOutputStream();
//next two line works ok...
System.err.println("Type: " + request.getContentType());
System.err.println("Content Length: " + request.getContentLength());
//but this do not return any bytes (jams) and also
//in.availabel()- function returns 0.
System.err.println("Read byte: " +;

Everything should be ok, but just do not work. I'm quite beginner with Java and do not know is the problem my competence, web-server (Apache Tomcat/4.0-b1) or what. Please, help me.
Jorma Ikonen

Joined: Sep 17, 2001
Posts: 2
I think the fact you use sc.doInput(true) after sc.doOutput(true) made the connection only reads from source.
Jorma Ikonen
Ranch Hand

Joined: Sep 17, 2001
Posts: 49
Hi Judy,
I really love you!
It seems that I have had very bad lucky. At the beginning I had the setDoInput first as described in, but the example there didn't work, because they used URLConnection instead of HttpURLConnection (setRequestMethod is required, because URLConnection invokes only the doGet()-method and fails there). So, while I was tracking the first problem I caused accidentally the next one by slipping the setDoInput and setDoOutput upside down... life is life.
Many hugs, thanks, and greetings from the north pole.
I agree. Here's the link:
subject: How to use post-method with applet and servlet
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