Write File in Applet

Question

I'm a student. I will be very happy if you could help!
I'm writing an self-signed applet that runs on browser.
Luckily there is no error shown in the java console when i run the applet.
however, i can't store information to a file which is placed at the server(where my applet is placed).
The biggest problem is there is NO ERROR message shown in the java console...
everything seems running very well, except THE FILE IS NOT UPDATE!
my source code for writing file:
try{
URL url1 = new URL("http://appletServer/~doris/1/User.properties");
URLConnection con=url1.openConnection();
con.setDoOutput(true);
OutputStream out = con.getOutputStream();     
props.store(out, "User properties of NAMS");//"props" is a property that contains some properties information.
catch(Exception e){
System.err.println("Error: " +e);
Thanks for your attention!

Answer 1

try{
URL url = new URL("");
URLConnection con = url.openConnection();
con.setDoOutput(true);
con.setDoInput(true);
con.setUseCaches(false);
con.setRequestProperty("Content-type", "text/plain");
con.setRequestProperty("Content-length", data.length()+"");
PrintStream out = new PrintStream(con.getOutputStream());
out.print(data);
out.flush();
out.close();
catch(Exception e){}