i am developing a appilication
which should update the client in
a regular basis.when ever the server
wants it should push the data to the
client.i don't want to use
client polling.How server push takes
place .plz help me.
Use JMS to send a message to your client?
thanks for responding.
i don'nt know how to
use JMS.my need is something
like this, the server needs
to push web pages to the
client.its like webcollaboration.
the server takes the control of
the client browser and pushes
the web pages.The pages are pushed
in some order.The browser should
get refreshed for every push.
can u help me regarding this.
one more thing i got to ask u.
iam developing a chat server with
max clients of 2000 people.
if i implement the chat server
as a servlet and the chat client
as applet will it be robust?
think in terms of load on the
Unless you are writing you're own browser then you will have to make use of an applet (aaaargghh!!) to do this. If you create a simple applet that can listen for push messages on a DatagramSocket or whatever and embed this in a non content frame. From here the applet can refresh the content pane without having to be reloaded itself.
Then you need a DatagramServer to sit on your server side and fire the push messages to the client applet.
The biggest problem is keeping track of which clients are active and belong to a given user - i worked round this by having the applet register itself (ie send a registration packet to the server) when start() is called and send an unregister packet on stop().
Hope thats of some help
If i use a servlet to push messages
to applet and the applet receives the
pushed message will it work if the
applet is behind the firewall?
If the load is more say some 1000 clients
are there will it be efficient?
If your server is behind a firewall you will have to ensure that the firewall is set up to allow incoming and outgoing datagram packets.
As for will it scale i can't say for sure as i've only tried this for a demo system. I don't see why it shouldn't your server only has to maintain a single datagram socket and you can just queue all the refresh messages. The one benefit is that you should have less load on the server than if the client just polls or the page is set to refresh at regular time intervals.
i've just tried that its working
fine with the client behind the firewall
I just want to do some more things here.
If the servlet sends a link ,i want that
link to be opened in a new browser window.
When ever the servlet pushes some url
that URL is refreshed in that window.
In this case also i do not want to use
client polling b'coz of the performance
whenever the server pushes the url it
should reflect in the window.
Got any idea how to it.
Glad to hear it is working !!
What you should be able to do is set the content of the datagram packet to be the url that you wish the browser to display. All you then do is when the applet recieves a packet it gets the content and redirects the content frame to there.
Check the applet documentation there is a method called showDocument() which takes a url and a target frame and will cause the content identified by the URL to be loaded into the named frame.
thanks a lot .Its working fine here.
i got a big doubt.
iam implementing a chat server which
should handle atleast 1000 clients.
i am planning to use socket for that.
Is there any restriction in the number of client
for the socket client?
Will it be scalable if i use sockets?
How abt using RMI for the same?
thanks and regards
i need to open a url from the applet.
now i use AppletContext.showDocument()
for that.but this method is supported
only in IE,Netsacape and HotJava.
other browser won't support that.Is
there any other way to open a url from
thanks and regards