java program monitors the Web Server

Thanks.

Do you have a simple codes how to using URLConnection and check response, thanks

http://javaalmanac.com/egs/java.net/Post.html

may be help ful to you for doing what objetc has suggested you.That was a simple & good suggestion.

http://javaalmanac.com/egs/java.net/GetHeaders.html

also this one.

another example here, showing how to check response code

http://java.sun.com/developer/TechTips/txtarchive/2003/Apr03_JohnZ.txt

Or just try a TCP/ IP socket connection to the port on which the web server listens. For example, if it listens on 8080:

Socket s = new Socket ( "localhost", 8080 ) ;

If an exception is thrown and it does not connect, then you know that the server is down. Keep the port-number in a properties-file. Then you can send an e-mail using:

http://www.javaalmanac.com/egs/javax.mail/SendApp.html

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;

public class TestServer {

            public static void main(String args[]) {
                  String urlString = "http://localhost:7001/console";
                  try {
                    URL url = new URL(urlString);
                    URLConnection connection =
                        url.openConnection();
                    if (connection instanceof HttpURLConnection) {
                        HttpURLConnection httpConnection =
                         (HttpURLConnection)connection;
                        httpConnection.connect();
                        int response =
                         httpConnection.getResponseCode();
                         System.out.println(response);
                        if(response>=400)
                        System.out.println("Error: Server is not  active");
                        else
                        if(response >=200&&response<400)
                        System.out.println("Server is active");
                    }
                  } catch (IOException e) {
                    e.printStackTrace();
                  }
              }
            }

I tested the above example on WebLogic you can change the URL & use suitably.
It works fine.

How exactly is the code posted by shivaspk any different to what I posted earlier?

You and hsivaspk gave me the same questin but i think i missed out your name.

Unfortunately I have closed this question. In my next question, i will give the points back to you. thanks

Any reason why you ignored the simplest approach described using:

>> Socket s = new Socket ( "localhost", 8080 ) ;

All you need to do is check if the web-server is up or not. URLs wil keep changing because you might keep adding/ moving/ removing web-applications and pages from the server so a URL which gives you one status-code today will give you another status-code tomorrow and then you have to make sure you handle all kinds of status-codes. Its a lot easier to just connect to the port and check if the server is connected or not.

That doesn’t guarantee that the SERVICES are running though. When we first started out looking for web server monitor s/w we were using GFI, but the email check only telneted into port 25 and checked that the server responded. In our particular case, our SMTP server was failing but was responding to the initial connection, so GFI didn’t catch the downtime and we were none the wiser.

With the code above, you can place the text "Server Up" in a database that is presented via a web page, so if you get the text "Server Up" returned, you know 100% that the web server and your database server are alive. Likewise, the only way to guarantee that your email server is working is to send and retrieve an email through it, as a 'dry' test is never going to be 100% effective.

colr__

Yes, it does not guarantee for services, and services/ their URLs can change (better to keep it in a properties-file if that's the case). The Q is simply about the web-server and about an individual service so I'll keep it to that.

What exactly does that mean?

colr__

> You know that we cannot see how the points are splitted :)

web server *is* a service :)

Is there 2 threads going on in here or something? Why has this been reopened? Why have I had my points stripped when I was already awarded them and by correct definition of the problem, I was the only one to answer?

colr__

Right, sorry, Ive never seen this before either.

colr__

:) It's ok :)
I am just trying to fix the things when needed :)

Venabili

Yes. object gave me the idea how to solve this problem. So i can start working on it.
colr gave me the same answer as obejct gave me, but colr gave me a complete source codes so that it save me alot of time. So that colr should get more points than object. I think this is fair for everyone.

By the way I do think you ppl help