Applet to php

[cms271828]

Hi, I'm looking to update a MySql database from an applet.
The 2 roots I was thinking were:
Applet->php->database
Applet->servlet->database

But my webhost doesn't allow servlets/jsp, so I would like to try the php route.
I've looked on the internet, but I can't find anything concrete to use, just lots of random waffle.

Essentially I just want to pass a String from my applet to a .php page on the server (Or a function from a php page), possibly by retrieving the String like a Form parameter on an html page.

Can anyone help?
Thanks

[Ezzaral]

Why not just use Applet->database? I think you may have to sign the applet, but you can use JDBC within an applet.

[cms271828]

I don't want to use signed applets, they are annoying.
I know I can use php, but doesn't seem theres any code on the internet to show this except for scraps of random bits of code which doesn't help.

[Ezzaral]

You would just need to make an HTTP request to the server with the appropriate GET or POST commands.

Here's an example for making a post request:
http://www.exampledepot.com/egs/java.net/Post.html

A GET request would be even easier since the data is actually in the url string.

[Ezzaral]

If you need a php reference, you might take a look at these:
Main Page - Practical PHP Programming
PHP Essentials - Techotopia
http://www.goodphptutorials.com

[cms271828]

Thanks very much!

I'll have a look at the code shortly.
Its nice to get some good comments instead of vague comments that dont help.

Thanks

[cms271828]

Ok, I got it to work!

[cms271828]

Ok, it works, but this is bonkers, if I miss out the line...
conn.getContentType();

Then it wont work, but it always works with it.

I've added the class below, if anyone wants to try it, they will see what I mean if they comment out

conn.getContentType();

Then run program a few times, and there is no change to textfile on server.
But when the line is included it should run everytime.

Its so weird, and I can't explain it, please can some other people try to see whats going on.

Thanks.

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import javax.swing.JApplet;
 
public class Main extends JApplet
{
 private static final long serialVersionUID = 1L;
 public Main()
 {
  System.out.println("IN CONSTRUCTOR");
  
  writeToFile();
  String data=readFile("[URL]http://www.colin-java.co.uk/Test/TESTFILE.txt[/URL]");
  
  System.out.println("data="+data);
 }
 
 
 public static String readFile(String location)
 {
  URL dataStream=null;
  try
  {
   dataStream = new URL(location);
  }
  catch (MalformedURLException e2)
  {
   e2.printStackTrace();
  }
  BufferedReader in=null;
  
  try
  {
   in = new BufferedReader(new InputStreamReader(dataStream.openStream()));
  }
  catch (IOException e2)
  {
   e2.printStackTrace();
  }
  String fullString="";
  String str;
  try
  { 
   int counter=1;
   while((str = in.readLine()) != null)
   {
       fullString+=(counter++)+". "+str+"\n";
   }
  
  }
  catch (IOException e1)
  {
   e1.printStackTrace();
  }
  
  return fullString;
 }
 
 public void writeToFile()
 {
  try
  { 
   URL url = new URL("[URL]http://colin-java.co.uk/Test/data.php[/URL]");
   URLConnection conn = url.openConnection();
   conn.getContentType(); 
  }
  catch (Exception e)
  {
   System.out.println("WRITE TO FILE ERROR: "+e.getMessage());
  }
 }
}

[Ezzaral]

I would imagine the php script is not being executed by simply opening the connection. openConnection() by itself may not generate a request on the script. The getContentType() is making a data request from the connection and that is what probably triggers the execution. getContent() would probably do the same.

[cms271828]

Thanks, I asked in javaranch too, they said the same thing.
Seems a bit unusual to do this though, I was trying everything to get it to work, then I printed out some data from 'conn' and it worked.
Gonna take a look at the API, that should help.

Thanks

[Ezzaral]

The API is a little bit vague on that, but since normally one makes a request for content or executes some read or write operation against the connection, the details of how scripts get executed probably isn't germaine to the general description of the API.