java - Get HTTP status code in asynchronous way -

i http status code before end of dopost method in java. example in python there self.send_response(200), sends status in asynchronous way?

 /**  * @see httpservlet#dopost(httpservletrequest request, httpservletresponse  * response)  *  */ @suppresswarnings("unchecked") @override protected void dopost(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {      //final result object       //i want send http status code 200 before task running      mythreadpool = executors.newfixedthreadpool(2);     future taskone = mythreadpool.submit(new runnable() {         @override         public void run() {             try {                 try {                     // first task                 } catch (servletexception e) {                     // todo auto-generated catch block                     e.printstacktrace();                 }             } catch (ioexception e) {                 // todo auto-generated catch block                 e.printstacktrace();             }         }      });      // task 2      .     . 

i'm not totally sure intention of code posted, can guess want kind of asynchronous processing, can send data client before request finishes?

for refer asynchronous servlets, described example here: https://blogs.oracle.com/enterprisetechtips/entry/asynchronous_support_in_servlet_3

there example seems serving what, assume, achieve:

@webservlet("/foo" asyncsupported=true)    public class myservlet extends httpservlet {         public void doget(httpservletrequest req, httpservletresponse res) {             ...             asynccontext actx = request.startasync(req, res);             scheduledthreadpoolexecutor executor = new threadpoolexecutor(10);             executor.execute(new asyncwebservice(actx));         }    }     public class asyncwebservice implements runnable {         asynccontext ctx;         public asyncwebservice(asynccontext ctx) {             this.ctx = ctx;         }         public void run() {             // invoke web service , save result in request attribute             // dispatch request render result jsp.             ctx.dispatch("/render.jsp");    } }