java - Sockets readInt not always working -

i'm building client-server java application. problem that, when send integer writeint(), blocks on readint().

client

printwriter socketout = new printwriter(sock.getoutputstream()); dataoutputstream d = new dataoutputstream(sock.getoutputstream()); string s = "user"; socketout.println(s); socketout.flush(); d.writeint(data[0]); d.flush(); d.writeint(data[1]); d.flush(); 

server

while(true){        system.out.println("listening clients...");        clientsock = serversock.accept();        scanner in = new scanner(clientsock.getinputstream());         string clienttype = in.nextline();         switch(clienttype){            case "resource":                new thread(new resourceservice(clientsock)).start();                break;            case "user":                new thread(new userservice(clientsock)).start();                break;        }      } 

user thread

@override     public void run(){         try{         datainputstream input = new datainputstream(user.getinputstream());         int = 0;         int = input.readint(); // blocks here.         int b = input.readint();         system.out.println(a);         system.out.println(b);         ... 

i'm trying distinguish between clients based on first string sent server. server reads int, , blocks. example of output is:

listening clients... listening clients... listening clients... listening clients... listening clients... 1                        // here server didn't block 100000 listening clients... 

probably not idea use datainputstream/dataoutputstream mixed scanner , printwriter. scanner , printwriter recommended more user interaction.

try use dataoutputstream , datainputstream.

client

dataoutputstream d = new dataoutputstream(sock.getoutputstream()); string s = "user"; d.writeutf(s); d.writeint(data[0]); d.flush(); d.writeint(data[1]); d.flush(); 

server

datainputstream input = new datainputstream(clientsock.getinputstream()); string clienttype = input.readutf();  switch(clienttype){     case "resource":         new thread(new resourceservice(input)).start();         break;     case "user":         new thread(new userservice(input)).start();         break; 

user thread

int = input.readint(); int b = input.readint(); system.out.println(a); system.out.println(b); 

note 1: datainputstream/dataoutputstream use own protocol write/read utf strings, no need use line termination.

note 2: methods of printwriter not throw i/o exceptions, have check calling checkerror (probably not problem here).