Please help with SSL POST: Servlet returns Error 500

Question

I am struggling for many days to get a Java program to log in to an SSL page. The program is supposed to track ADSL usage statistics from https://secure.telkomsa.net/titracker/, but I never seem to get around Server returned Error 500.
Could anyone please help me understand what I am doing wrong by looking at the method I used. (It seems on the server side it is a jsp servlet that handles authentication).
Any help is deeply appreciated!
I copy-paste the method directly from NetBeans:
CODE>
void connectHTTPS(String url){
try {
URL page = new URL(url); // login page necessary to get a jsp session cookie
//------------ SET UP SSL - is it right?
System.setProperty("java.protocol.handler.pkgs",
"com.sun.net.ssl.internal.www.protocol");
try {
//if we have the JSSE provider available,
//and it has not already been
//set, add it as a new provide to the Security class.
final Class clsFactory = Class.forName("com.sun.net.ssl.internal.ssl.Provider");
if( (null != clsFactory) && (null == Security.getProvider("SunJSSE")) )
Security.addProvider((Provider)clsFactory.newInstance());
} catch( ClassNotFoundException cfe ) {
throw new Exception("Unable to load the JSSE SSL stream handler." +
"Check classpath." + cfe.toString());
URLConnection urlc = page.openConnection();
urlc.setDoInput(true);
*Get the session id cookie set by the TelkomInternet java server
String cookie = urlc.getHeaderField("Set-Cookie");
//textpane.setText(totextpane);
textpane.setText(cookie);
//---------------- form an auth request and post it with the cookie
String postdata =URLEncoder.encode("ID_Field","UTF-8")+"="+URLEncoder.encode("myusrname","UTF-8")+"&"+URLEncoder.encode("PW_Field","UTF-8")+"="+URLEncoder.encode("mypwd","UTF-8")+"&"+URLEncoder.encode("confirm","UTF-8")+"="+URLEncoder.encode("false","UTF-8");
// set the servlet that handles authentication as target
URL page2 = new URL("https://secure.telkomsa.net/titracker/servlet/LoginServlet");
// cast to httpConn to enable setRequestMethod()
HttpURLConnection urlc2 = (HttpURLConnection)page2.openConnection();
// formulate request with POST data urlc2.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
urlc2.setRequestMethod("POST"); // experimental
urlc2.setRequestProperty("Content-Length",""+postdata.length());
urlc2.setRequestProperty("User-Agent","Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 4.0)");
urlc2.setRequestProperty("Accept-Language","en-us");
urlc2.setUseCaches(false);
urlc2.setDoOutput(true);
urlc2.setDoInput(true);
urlc2.setFollowRedirects(true); // ??
//send cookies
urlc2.setRequestProperty("Set-Cookie", cookie); // or "Cookie" - doesn't work either
//write other data
PrintWriter out = new PrintWriter(urlc2.getOutputStream());
out.print(postdata); // username and password here
out.flush();
out.close();
//---------------- get the authenticated page with real ADSL statistics
BufferedReader br = new BufferedReader(new InputStreamReader(urlc2.getInputStream()));
String totextpane = "";
String buffer = "";
while (buffer != null) {
try {
totextpane = totextpane + "\n" + buffer;
buffer = br.readLine();
} catch (IOException ioe) {
ioe.printStackTrace();
break;
textpane.setText(totextpane);
} catch (Exception ex) {
System.err.println(ex.getMessage());
---- END CODE---
Thank you very much for any attempt at helping with this problem!

Answer 1

I am struggling for many days to get a Java program to log in to an SSL page. The program is supposed to track ADSL usage statistics from https://secure.telkomsa.net/titracker/, but I never seem to get around Server returned Error 500.
Could anyone please help me understand what I am doing wrong by looking at the method I used. (It seems on the server side it is a jsp servlet that handles authentication).
Any help is deeply appreciated!
I copy-paste the method directly from NetBeans:
CODE>
void connectHTTPS(String url){
try {
URL page = new URL(url); // login page necessary to get a jsp session cookie
//------------ SET UP SSL - is it right?
System.setProperty("java.protocol.handler.pkgs",
"com.sun.net.ssl.internal.www.protocol");
try {
//if we have the JSSE provider available,
//and it has not already been
//set, add it as a new provide to the Security class.
final Class clsFactory = Class.forName("com.sun.net.ssl.internal.ssl.Provider");
if( (null != clsFactory) && (null == Security.getProvider("SunJSSE")) )
Security.addProvider((Provider)clsFactory.newInstance());
} catch( ClassNotFoundException cfe ) {
throw new Exception("Unable to load the JSSE SSL stream handler." +
"Check classpath." + cfe.toString());
URLConnection urlc = page.openConnection();
urlc.setDoInput(true);
*Get the session id cookie set by the TelkomInternet java server
String cookie = urlc.getHeaderField("Set-Cookie");
//textpane.setText(totextpane);
textpane.setText(cookie);
//---------------- form an auth request and post it with the cookie
String postdata =URLEncoder.encode("ID_Field","UTF-8")+"="+URLEncoder.encode("myusrname","UTF-8")+"&"+URLEncoder.encode("PW_Field","UTF-8")+"="+URLEncoder.encode("mypwd","UTF-8")+"&"+URLEncoder.encode("confirm","UTF-8")+"="+URLEncoder.encode("false","UTF-8");
// set the servlet that handles authentication as target
URL page2 = new URL("https://secure.telkomsa.net/titracker/servlet/LoginServlet");
// cast to httpConn to enable setRequestMethod()
HttpURLConnection urlc2 = (HttpURLConnection)page2.openConnection();
// formulate request with POST data urlc2.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
urlc2.setRequestMethod("POST"); // experimental
urlc2.setRequestProperty("Content-Length",""+postdata.length());
urlc2.setRequestProperty("User-Agent","Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 4.0)");
urlc2.setRequestProperty("Accept-Language","en-us");
urlc2.setUseCaches(false);
urlc2.setDoOutput(true);
urlc2.setDoInput(true);
urlc2.setFollowRedirects(true); // ??
//send cookies
urlc2.setRequestProperty("Set-Cookie", cookie); // or "Cookie" - doesn't work either
//write other data
PrintWriter out = new PrintWriter(urlc2.getOutputStream());
out.print(postdata); // username and password here
out.flush();
out.close();
//---------------- get the authenticated page with real ADSL statistics
BufferedReader br = new BufferedReader(new InputStreamReader(urlc2.getInputStream()));
String totextpane = "";
String buffer = "";
while (buffer != null) {
try {
totextpane = totextpane + "\n" + buffer;
buffer = br.readLine();
} catch (IOException ioe) {
ioe.printStackTrace();
break;
textpane.setText(totextpane);
} catch (Exception ex) {
System.err.println(ex.getMessage());
---- END CODE---
Thank you very much for any attempt at helping with this problem!