HttpURLConnection got stack when trying to invoke

[Meir Yan]

Hello

im trying to perform http get request with HttpURLConnection when tomcat server is starting up

the function is located in the servlet init method , but it seams that when it reached to the part it reform the connection

the connection got stocked .

here is my code:

public void init(ServletConfig config) throws ServletException {
 
System.out.println("TestInit");
 
String urlString= "http://localhost:8070/jsp/Test.jsp?jsp_precompile=true"
 
HttpURLConnection connection; 
 
BufferedReader in; 
 
try { 
 
URL url = new URL(urlString); 
 
connection = (HttpURLConnection)url.openConnection(); 
 

System.out.println(connection.getResponseCode());
 

in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
 

System.out.println("Done Compileing jsp TestInit");
 
} catch (IOException e) { 
 
e.printStackTrace(); 
 
} 
 
}

[Ben Souther]

Are you trying to make a request to an application in the same container?

If so, you may be in a deadlock situation.

App A tries to start first

App A tries to connect to app B on startup

App B isn't running yet

App A can't finish starting until the init method fishes (but can't because it's waiting for app B

App B and start until app A has started.

[Meir Yan]

Is there any way to over come this ?
mybe to some how to run this after the application done loading ?

[Bear Bibeault]

It would probably help greatly if you told us what you are actually trying to accomplish!

[Ben Souther]

There is nothing in the servlet spec for dictating which apps get loaded first. I don't know if any containers provide their own way to do this.
I use Tomcat and I know it doesn't.

Unless you know that the container that you're using has a way to control the order of app deployment, you should avoid having one app depend on another; especially during startup.

You might want to have this initialization take place when a servlet is hit for the first time. If you do this, you should also have a way to gracefully handle a situation where the servlet gets hit before the dependency app has started. Something like an error page that asks the user to try again in a moment.

Another option is to run two separate container instances, one for each app.


As Bear asked, why are you doing this in the first place?

[Meir Yan]

Hello all and thanks for the reply
What im trying to do is to recompile the jsp's before the application loading.
I was fallowing this link :
http://www.j2eegeek.com/blog/2004/05/03/a-different-twist-on-pre-compiling-jsps/
But instead of loading the jsp's from the web.xml im looping throw all my jsp's

[Ben Souther]

Originally posted by Meir Yan:
Hello all and thanks for the reply
What im trying to do is to recompile the jsp's before the application loading.
I was fallowing this link :
http://www.j2eegeek.com/blog/2004/05/03/a-different-twist-on-pre-compiling-jsps/
But instead of loading the jsp's from the web.xml im looping throw all my jsp's

I started reading that article and it looks interesting.
I'll read the whole thing later today.