Java socket connection time out in Android Implementation -

i'm writing simple android code file transfer on java sockets. first of all, hard coded file path in server implementation check if files received @ client side or not. worked fine. created simple file browser separate java class user browse through files , select them well. purpose, created simple intent launch file browser class (the intent fired after socket initialization). problem starts here. before file browser thing, app working fine (with pre-defined set of files). now, i'm getting socket closed exception every time run app. doesn't reach intent firing stage. please me. i'm self taught , still learning android programming. here code snippets:

server:

public class mainactivity extends activity { arraylist<file> filearray = new arraylist<file>(); arraylist<string> filepathnamearray = new arraylist<string>(); socket socket = null; serversocket serversocket = null; int request_code = 1;  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);      thread trd = new thread(new runnable() {         @override         public void run() {             initializeserver();             intent launchfilemanager = new intent(getbasecontext(),                     filechooseractivity.class);             startactivityforresult(launchfilemanager, request_code);             if (!filearray.isempty()) {                 (int = 0; < filearray.size(); i++)                     copyfile(filearray.get(i), filearray.get(i).getname());             }         }     });     trd.start(); } private void initializeserver() {     try {         serversocket = new serversocket(4444);     } catch (ioexception e) {         e.printstacktrace();         log.d("listen failed", "listening port 4444 failed");     }     try {         socket = serversocket.accept();     } catch (ioexception e) {         e.printstacktrace();         log.d("binding failed", "couldn't accept socket connection");     } }  @override protected void onactivityresult(int requestcode, int resultcode, intent data) {     if (requestcode == request_code) {         if (resultcode == result_ok) {             filepathnamearray = data.getextras().getstringarraylist("key");// file uri received             for(int f=0;f<filepathnamearray.size();f++){                 filearray.add(new file(filepathnamearray.get(f))); //create file array             }         }         if (resultcode == result_canceled) {             toast canceltoast = toast.maketext(getbasecontext(),                     "nothing selected", toast.length_short);             canceltoast.show();         }     } } 

filechooser returning intent result:

selectiondone.setonclicklistener(new view.onclicklistener() {          @override         public void onclick(view v) {             // selfilepathlist file path list of selected files             intent returnintent=new intent();             returnintent.putstringarraylistextra("key", selfilepathlist);             setresult(result_ok, returnintent);             finish();         }     }); } 

client:

public class receiver { static socket socket = null;  public static void main(string[] args) {     inetaddress serverip;     try {         serverip = inetaddress.getbyname("10.87.3.91");         socket = new socket(serverip, 4444);         if (socket != null) {             system.out.println("connection established!!");             (int j = 0; j < 5; j++)                 receivedos();         }     } catch (unknownhostexception e) {         e.printstacktrace();     } catch (ioexception e) {         e.printstacktrace();     }  } 

i've added necessary manifest permission:

<uses-sdk     android:minsdkversion="8"     android:targetsdkversion="18" />  <uses-permission android:name="android.permission.access_network_state" /> <uses-permission android:name="android.permission.internet" /> <uses-permission android:name="android.permission.access_wifi_state" /> <uses-permission android:name="android.permission.change_wifi_state" /> <uses-permission android:name="android.permission.write_external_storage" /> <uses-permission android:name="android.permission.read_external_storage"/> 

console output:

03-24 22:26:02.452: w/system.err(22973): java.net.socketexception: socket closed 03-24 22:26:02.452: w/system.err(22973):    @ libcore.io.posix.accept(native method) 03-24 22:26:02.452: w/system.err(22973):    @ libcore.io.blockguardos.accept(blockguardos.java:55) 03-24 22:26:02.452: w/system.err(22973):    @ java.net.plainsocketimpl.accept(plainsocketimpl.java:98) 03-24 22:26:02.452: w/system.err(22973):    @ java.net.serversocket.implaccept(serversocket.java:202) 03-24 22:26:02.452: w/system.err(22973):    @ java.net.serversocket.accept(serversocket.java:127) 03-24 22:26:02.452: w/system.err(22973):    @ com.example.zztest.mainactivity.initializeserver(mainactivity.java:57) 03-24 22:26:02.452: w/system.err(22973):    @ com.example.zztest.mainactivity.access$0(mainactivity.java:49) 03-24 22:26:02.452: w/system.err(22973):    @ com.example.zztest.mainactivity$1.run(mainactivity.java:36) 03-24 22:26:02.462: w/system.err(22973):    @ java.lang.thread.run(thread.java:856) 03-24 22:26:02.462: d/binding failed(22973): couldn't accept socket connection 

any idea or suggestion highly appreciated. in advance!