java - how to send instruction to server every five second -

i have written part of code server receive instruction client , send request client. want send instruction(json message) client every 5 second. how that?

public static void main(string[] args) throws ioexception, interruptedexception, parseexception {      synchronisedfile fromfile = null;     fromfile=new synchronisedfile("file.txt");     fromfile.checkfilestate();     int counter = 1;     int receivedcounter = 1;     string receivedtype=null;      datagramsocket clientsocket = new datagramsocket();      inetaddress ipaddress = inetaddress.getbyname("localhost");     byte[] senddata = new byte[1024];     byte[] receivedata = new byte[1024];      while(true){          instruction inst = fromfile.nextinstruction();         //system.out.println(inst.tojson());          jsonobject jo = new jsonobject();         jo.put("type", "inst");         jo.put("inst", inst.tojson());         jo.put("counter", counter);         //system.out.println(jo);         counter++;          senddata = jo.tostring().getbytes();          datagrampacket sendpacket = new datagrampacket(senddata, senddata.length, ipaddress, 4144);         clientsocket.send(sendpacket);          datagrampacket receivepacket = new datagrampacket(receivedata, receivedata.length);         clientsocket.receive(receivepacket);         string receivedmessage = new string(receivepacket.getdata());          string subreceivedmessage = receivedmessage.trim();          final jsonparser parser = new jsonparser();         jsonobject obj;         obj = (jsonobject) parser.parse(subreceivedmessage); 

you use scheduledexecutorservice. here basic example using returned result using (callable) below. if don't need result can use runnable method instead similar signature:

scheduledexecutorservice scheduledexecutorservice = executors.newscheduledthreadpool(10); scheduledfuture<string> scheduledfuture = scheduledexecutorservice.schedule(new callable<string>() {     @override     public string call() throws exception {         return "result";     } }, 5, timeunit.seconds);