Can a client get servlet's responses without a request?

Question

In the traditional way for every client request I get servlet response.
something like this:

HttpResponse response = client.execute(request)

Now I want to get updates from my servlet every time interval.
How can i catch the server's response?

For comparison when I worked with sockets the code looked something like this:

public void run()
{
    while(true)
    {            
        Object serverMessage = inStream.readObject();               
        // Do somthing with serverMessage
    }
}

What answer are you looking for beyond "put the `response = ` line inside the loop"? — Kirk Woll, Apr 18 '12 at 22:38

score 1 · Answer 1 · answered Apr 18 '12 at 22:50

1

No. The client will have to make more requests to which the server -> servlet then responds.

You can however (by e.g. Javascript) try to make the client send a request at a regular interval.

answered Apr 18 '12 at 22:50

ChristopheD

112,638
29
165
179

score 1 · Accepted Answer · edited May 23 '17 at 11:55

1

You can simulate a server to client push with an approach called long polling, addressed here: Long Polling example
HTTP is a request driven protocol. You could explore other messaging protocols depending on what you're doing. Anything from Web Sockets to basic TCP, to a variety of frameworks that build ostensibly richer apis on top of tcp. What are you trying to accomplish?

edited May 23 '17 at 11:55

Community

1
1

answered Apr 19 '12 at 00:37

verrdon

71
2

Can a client get servlet's responses without a request?

2 Answers2