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Chapter 17 Using Applets As Servlet Front Ends

Listing 17.7 SendPost.java (continued)

      // Tell browser to allow me to send data to server.

      connection.setDoOutput(true);

      ByteArrayOutputStream byteStream =

        new ByteArrayOutputStream(512); // Grows if necessary

      // Stream that writes into buffer

      PrintWriter out = new PrintWriter(byteStream, true);

      String postData =

        "firstName=" + encodedValue(firstNameField) +

        "&lastName=" + encodedValue(lastNameField) +

        "&emailAddress=" + encodedValue(emailAddressField);

      // Write POST data into local buffer

      out.print(postData);

      out.flush(); // Flush since above used print, not println

      // POST requests are required to have Content Length

      String lengthString =

        String.valueOf(byteStream.size());

      connection.setRequestProperty

        ("Content Length", lengthString);

      // Netscape sets the Content Type to multipart/form data

      // by default. So, if you want to send regular form data,

      // you need to set it to

      // application/x www form urlencoded, which is the

      // default for Internet Explorer. If you send

      // serialized POST data with an ObjectOutputStream,

      // the Content Type is irrelevant, so you could

      // omit this step.

      connection.setRequestProperty

        ("Content Type", "application/x www form urlencoded");

      // Write POST data to real output stream

      byteStream.writeTo(connection.getOutputStream());

      BufferedReader in =

        new BufferedReader(new InputStreamReader

                             (connection.getInputStream()));

      String line;

      String linefeed = "\n";

      resultsArea.setText("");

      while((line = in.readLine()) != null) {

        resultsArea.append(line);

        resultsArea.append(linefeed);

      }

    } catch(IOException ioe) {

      // Print debug info in Java Console

      System.out.println("IOException: " + ioe);

    }

  }

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