java - How to increase the buffer size in Handler? -

i'm working on plotting graph on android app. want use buffer size equal 512 store incoming data arduino. after buffer full graph plotted , keep going. how can change code achieve this?

handler mhandler = new handler(){     @override     public void handlemessage(message msg) {         // todo auto-generated method stub         super.handlemessage(msg);         switch(msg.what){         case bluetooth.success_connect:             bluetooth.connectedthread = new bluetooth.connectedthread((bluetoothsocket)msg.obj);             toast.maketext(getapplicationcontext(), "connected!", 0).show();             string s = "successfully connected";             bluetooth.connectedthread.start();             break;         case bluetooth.message_read:              byte[] readbuf = (byte[]) msg.obj;             string strincom = new string(readbuf, 0, 5);                 // create string bytes array              log.d("strincom", strincom);             if (strincom.indexof('.')==2 && strincom.indexof('s')==0){                 strincom = strincom.replace("s", "");                 if (isfloatnumber(strincom)){                     series.appenddata(new graphviewdata(graph2lastxvalue,double.parsedouble(strincom)),autoscrollx);                      //x-axis control                     if (graph2lastxvalue >= xview && lock == true){                         series.resetdata(new graphviewdata[] {});                         graph2lastxvalue = 0;                     }else graph2lastxvalue += 0.1;                      if(lock == true)                         graphview.setviewport(0, xview);                     else                         graphview.setviewport(graph2lastxvalue-xview, xview);                      //refresh                     graphview.removeview(graphview);                     graphview.addview(graphview);                  }             }              break;         }     }      public boolean isfloatnumber(string num){         //log.d("checkfloatnum", num);         try{             double.parsedouble(num);         } catch(numberformatexception nfe) {             return false;         }         return true;     }  }; 

this bluetooth code:

public class bluetooth extends activity implements onitemclicklistener{  public static void disconnect(){     if (connectedthread != null) {         connectedthread.cancel();          connectedthread = null;     } }  public static void gethandler(handler handler){//bluetooth handler     mhandler = handler; } static handler mhandler = new handler();  static connectedthread connectedthread; public static final uuid my_uuid = uuid.fromstring("00001101-0000-1000-8000-00805f9b34fb"); protected static final int success_connect = 0; protected static final int message_read = 1; arrayadapter<string> listadapter; listview listview; static bluetoothadapter btadapter; set<bluetoothdevice> devicesarray; arraylist<string> paireddevices; arraylist<bluetoothdevice> devices; intentfilter filter; broadcastreceiver receiver;  @override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_bluetooth);     init();     if (btadapter==null){         toast.maketext(getapplicationcontext(), "no bluetooth detected", 0).show();         finish();     }else{         if (!btadapter.isenabled()){             turnonbt();         }         getpaireddevices();         startdiscovery();     }  }   private void startdiscovery() {     // todo auto-generated method stub     btadapter.canceldiscovery();     btadapter.startdiscovery(); }  private void turnonbt() {     intent intent = new intent(bluetoothadapter.action_request_enable);     startactivityforresult(intent, 1); }  private void getpaireddevices() {     devicesarray = btadapter.getbondeddevices();     if (devicesarray.size()>0){         for(bluetoothdevice device:devicesarray){             paireddevices.add(device.getname());         }     } }  private void init(){     listview = (listview)findviewbyid(r.id.listview);     listview.setonitemclicklistener(this);     listadapter = new arrayadapter<string>(this, android.r.layout.simple_list_item_1,0);     listview.setadapter(listadapter);     btadapter = bluetoothadapter.getdefaultadapter();     paireddevices = new arraylist<string>();     filter = new intentfilter(bluetoothdevice.action_found);     devices = new arraylist<bluetoothdevice>();      receiver = new broadcastreceiver(){         @override         public void onreceive(context context, intent intent) {             string action = intent.getaction();             if (bluetoothdevice.action_found.equals(action)){                 bluetoothdevice device = intent.getparcelableextra(bluetoothdevice.extra_device);                 devices.add(device);                 string s = "";                 for(int a=0;a<paireddevices.size();a++){                     if (device.getname().equals(paireddevices.get(a))){                         //append                         s = "(paired)";                         break;                     }                 }                 listadapter.add(device.getname()+" "+s+" "+"\n"+device.getaddress());              }else if (bluetoothadapter.action_discovery_started.equals(action)){              }else if (bluetoothadapter.action_discovery_finished.equals(action)){              }else if (bluetoothadapter.action_state_changed.equals(action)){                 if (btadapter.getstate() == btadapter.state_off){                     turnonbt();                 }             }           }      };      registerreceiver(receiver, filter);     intentfilter filter = new intentfilter(bluetoothadapter.action_discovery_started);     registerreceiver(receiver, filter);     filter = new intentfilter(bluetoothadapter.action_discovery_finished);     registerreceiver(receiver, filter);     filter = new intentfilter(bluetoothadapter.action_state_changed); }  @override protected void onpause() {     // todo auto-generated method stub     super.onpause();     unregisterreceiver(receiver); }  protected void onactivityresult(int requestcode, int resultcode, intent data){     super.onactivityresult(requestcode, resultcode, data);     if (resultcode == result_canceled){         toast.maketext(getapplicationcontext(), "bluetooth must enabled continue", toast.length_short).show();         finish();     } }  @override public void onitemclick(adapterview<?> arg0, view arg1, int arg2, long arg3) {     // todo auto-generated method stub     if (btadapter.isdiscovering()){         btadapter.canceldiscovery();     }     if (listadapter.getitem(arg2).contains("(paired)")){          bluetoothdevice selecteddevice = devices.get(arg2);         connectthread connect = new connectthread(selecteddevice);         connect.start();     }else {         toast.maketext(getapplicationcontext(), "device not paired", 0).show();     } }  private class connectthread extends thread {     private final bluetoothsocket mmsocket;     private final bluetoothdevice mmdevice;      public connectthread(bluetoothdevice device) {         // use temporary object later assigned mmsocket,         // because mmsocket final         bluetoothsocket tmp = null;         mmdevice = device;          // bluetoothsocket connect given bluetoothdevice         try {             // my_uuid app's uuid string, used server code             tmp = device.createrfcommsockettoservicerecord(my_uuid);         } catch (ioexception e) { }         mmsocket = tmp;     }      public void run() {         // cancel discovery because slow down connection         btadapter.canceldiscovery();          try {             // connect device through socket. block             // until succeeds or throws exception             mmsocket.connect();             //connectedthread = new connectedthread(mmsocket);         } catch (ioexception connectexception) {             // unable connect; close socket , out             try {                 mmsocket.close();             } catch (ioexception closeexception) { }             return;         }          // work manage connection (in separate thread)         mhandler.obtainmessage(success_connect, mmsocket).sendtotarget();     }      /** cancel in-progress connection, , close socket */     public void cancel() {         try {             mmsocket.close();         } catch (ioexception e) { }     } }  static class connectedthread extends thread {     private final bluetoothsocket mmsocket;     private final inputstream mminstream;     private final outputstream mmoutstream;      public connectedthread(bluetoothsocket socket) {         mmsocket = socket;         inputstream tmpin = null;         outputstream tmpout = null;          // input , output streams, using temp objects because         // member streams final         try {             tmpin = socket.getinputstream();             tmpout = socket.getoutputstream();         } catch (ioexception e) { }          mminstream = tmpin;         mmoutstream = tmpout;     }     stringbuffer sbb = new stringbuffer();     public void run() {          byte[] buffer;  // buffer store stream         int bytes; // bytes returned read()          // keep listening inputstream until exception occurs         while (true) {             try {                 try {                     sleep(30);                 } catch (interruptedexception e) {                     // todo auto-generated catch block                     e.printstacktrace();                 }                  buffer = new byte[1024];                 // read inputstream                 bytes = mminstream.read(buffer);                 // send obtained bytes ui activity                 mhandler.obtainmessage(message_read, bytes, -1, buffer).sendtotarget();             } catch (ioexception e) {                 break;             }         }     }      /* call main activity send data remote device */     public void write(string income) {          try {             mmoutstream.write(income.getbytes());             for(int i=0;i<income.getbytes().length;i++)             log.v("outstream"+integer.tostring(i),character.tostring((char)(integer.parseint(byte.tostring(income.getbytes()[i])))));             try {                 thread.sleep(20);             } catch (interruptedexception e) {                 // todo auto-generated catch block                 e.printstacktrace();             }         } catch (ioexception e) { }     }      /* call main activity shutdown connection */     public void cancel() {         try {             mmsocket.close();         } catch (ioexception e) { }     } } 

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