URL writing

Question

Hi,
I am getting very confused ! I have a prog that reads a file from a web server, and displays it in a TextArea. The user can then change the data in this TextArea, and I then want ot write it back to the web server. The number of choices for doing this seem vast, which is the best one to use ? I read the file like this :
URL source = new URL(getCodeBase(), f);
URLConnection url = source.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(source.openStream()));
while(section < 6) {  // read all data lines, for 5 sections.
          data = in.readLine();
          rawArray[rawCt]=data; //populate the rawArray;
          rawCt++;
Once I have an array of data, I populate the textarea (tArea1) and change it about. I then want to put it back, but my little grey cells are no longer working. Can someone please help !
regards
KPJ

Answer 1

Hi Guys,
for reference, I sorted this problem out. I needed to use a perl cgi prog
to take the data and save it. The java code had to emulate the HTTP POST command, and getting the syntax sorted for this was interesting ! The working solution for anyone interested is as follows:
public void SendData(String data) throws Exception {
     tArea1.append("\n\n************   Sending Data   ************\n");
     URL url = new URL("http","www.lagfc.co.uk","/cgi-bin/PerlUpdate.cgi");
     URLConnection ucon = url.openConnection();
     ucon.setDoOutput(true);
     ucon.setDoInput(true);
     ucon.setUseCaches(false);
     ucon.setRequestProperty("Content-type", "text/plain");
     ucon.setRequestProperty("Content-length", data.length()+"");
          PrintStream out = new PrintStream(ucon.getOutputStream());
     out.print(data);
     out.flush();
     out.close();
     tArea1.setText("*************************************");
     tArea1.append("\n*****     Data sent to host     *****\n");
          DataInputStream in = new DataInputStream(ucon.getInputStream());
     String s;
     while((s=in.readLine()) !=null){ // Read in response from CGI
     tArea1.append(s);
     in.close();
          tArea1.append("\n*************************************\n");
   } // end of sendDataThe CGI File that handles the data is
#! /usr/bin/perl
# This program allows a java Applet to write direct to a web server  #
# It is based on an article "Java Jive" by Scott Clark               #
$Fname = "e:/absolute/address/of/file/14.rst";
$SFC = "e:/absolute/address/of/file/savecount.dat";
# example "e:/domains/mydomain.co.uk/Stats/Under14.rst"
print "content-type: text/html\n\n";
# print content type header top the browser
if ($ENV{ 'REQUEST_METHOD'} eq 'POST'){
     read(STDIN,$datain, $ENV{ 'CONTENT_LENGTH'});
     open(SFC, $SFC) or die "Can't open Save Count File";
     $count = <SFC>;
     close(SFC);
     $Backup = substr($Fname,0,length($Fname)-3).$count;
     if (-e $Backup) {unlink($Backup); } # if the $Backup file exists, delete and then....
     rename($Fname,$Backup);            # rename current file to latest save file
     open(SFC,">$SFC");
     $count = $count+1;
     if ($count eq 1000){
          $count = 995;                 # change this number to 997 for 3 backup files
     }                                     # or 990 for 10 backup files
     print SFC $count;                   # increment the save file count
     close (SFC);     
     open(OUT,">$Fname") or die "Session not possible:$!";
     print OUT $datain;                   # write out the new data file
     print "*****  Data Transfer completed  *****";
close(OUT);
#close the filehandle
exit 0;
#exit the code
1; #return trueThe cgi file will keep a number of file copies for you. A note of caution. Anyone with access to your applet can update the file, and screw your data. Anyone contemplating this approach should be aware of that. This may not be the best approach for what you want to do. I may extend the cgi file to put in a password.... undecided yet.
Thanks for all the tips from the guys in the forum. Good Luck... KPJ