android - Service is running in multiple instance -

i have created background service work if application killed. in service getting data sensor. seems service returning sensors value multiple times in second resulting of application getting hanged.

here service:

public class stepcounterservice extends service {     private static final string log_tag = "foregroundservice";      public static boolean flag = false;      private sensormanager msensormanager;     private stepdetector detector;      private powermanager mpowermanager;     private wakelock mwakelock;      @override     public ibinder onbind(intent intent) {         // todo auto-generated method stub         return null;     }      @override     public int onstartcommand(intent intent, int flags, int startid) {        /* msensormanager = (sensormanager) this.getsystemservice(sensor_service);          msensormanager.registerlistener(detector,                 msensormanager.getdefaultsensor(sensor.type_accelerometer),                 sensormanager.sensor_delay_fastest);*/          log.d("zzz", "start command");          return start_sticky;     }      @override     public void oncreate() {         // todo auto-generated method stub         super.oncreate();         new stepcountmanager(this);         log.d("zzz", "create");          flag = true;          log.e("service_started", "");         detector = new stepdetector(this);           msensormanager = (sensormanager) this.getsystemservice(sensor_service);          msensormanager.registerlistener(detector,                 msensormanager.getdefaultsensor(sensor.type_accelerometer),                 sensormanager.sensor_delay_fastest);           mpowermanager = (powermanager)                 .getsystemservice(context.power_service);         mwakelock = mpowermanager.newwakelock(powermanager.screen_dim_wake_lock                 | powermanager.acquire_causes_wakeup, "s");         mwakelock.acquire();         reloadsettings();     }      @override     public void ondestroy() {         // todo auto-generated method stub         super.ondestroy();         flag = false;         if (detector != null) {             msensormanager.unregisterlistener(detector);         }          if (mwakelock != null) {             mwakelock.release();         }          log.e("service_destroyed", "");     }      public void reloadsettings() {          if (detector != null) {             detector.setsensitivity(                     float.valueof("10")             );         }       }      @override     public void ontaskremoved(intent rootintent) {         super.ontaskremoved(rootintent);         intent restartservice = new intent(getapplicationcontext(),                 this.getclass());         restartservice.setpackage(getpackagename());         pendingintent restartservicepi = pendingintent.getservice(                 getapplicationcontext(), 1, restartservice,                 pendingintent.flag_one_shot);          //restart service once has been killed android   //        alarmmanager alarmservice = (alarmmanager)getapplicationcontext().getsystemservice(context.alarm_service); //        alarmservice.set(alarmmanager.elapsed_realtime, systemclock.elapsedrealtime() +100, restartservicepi);          ((alarmmanager) getsystemservice(context.alarm_service))                 .set(alarmmanager.rtc, system.currenttimemillis() + 1000, pendingintent                         .getservice(this, 3, new intent(this, stepcounterservice.class), 0));      }  } 

here class implementing sensoreventlistener:

public class stepdetector implements sensoreventlistener {       public static updatestepcount mstepsupdater;       public static int current_setp = 0;      public static float sensitivity = 0;   //sensitivity      private float mlastvalues[] = new float[3 * 2];     private float mscale[] = new float[2];     private float myoffset;     private static long end = 0;     private static long start = 0;     private float   mlimit = 10;       private float mlastdirections[] = new float[3 * 2];     private float mlastextremes[][] = { new float[3 * 2], new float[3 * 2] };     private float mlastdiff[] = new float[3 * 2];     private int mlastmatch = -1;       public stepdetector(context context) {         // todo auto-generated constructor stub         super();         int h = 480;         myoffset = h * 0.5f;         mscale[0] = -(h * 0.5f * (1.0f / (sensormanager.standard_gravity * 2)));         mscale[1] = -(h * 0.5f * (1.0f / (sensormanager.magnetic_field_earth_max)));      }     public void setsensitivity(float sensitivity) {         mlimit = sensitivity; // 1.97  2.96  4.44  6.66  10.00  15.00  22.50  33.75  50.62     }       @override     public void onsensorchanged(sensorevent event) {          log.d("zzz", "sensor changed");         sensor sensor = event.sensor;         // log.i(constant.step_detector, "onsensorchanged");         synchronized (this) {             if (sensor.gettype() == sensor.type_orientation) {             } else {                 int j = (sensor.gettype() == sensor.type_accelerometer) ? 1 : 0;                 if (j == 1) {                     float vsum = 0;                     (int = 0; < 3; i++) {                         final float v = myoffset + event.values[i] * mscale[j];                         vsum += v;                     }                     int k = 0;                     float v = vsum / 3;                      float direction = (v > mlastvalues[k] ? 1: (v < mlastvalues[k] ? -1 : 0));                     if (direction == -mlastdirections[k]) {                         // direction changed                         int exttype = (direction > 0 ? 0 : 1); // minimum or                         // maximum?                         mlastextremes[exttype][k] = mlastvalues[k];                         float diff = math.abs(mlastextremes[exttype][k]- mlastextremes[1 - exttype][k]);                          if (diff > mlimit) {                             boolean isalmostaslargeasprevious = diff > (mlastdiff[k] * 2 / 3);                             boolean ispreviouslargeenough = mlastdiff[k] > (diff / 3);                             boolean isnotcontra = (mlastmatch != 1 - exttype);                              if (isalmostaslargeasprevious && ispreviouslargeenough && isnotcontra) {                                 end = system.currenttimemillis();                                 if (end - start > 500) {                                     log.i("step_detector", "current_setp:"                                             + current_setp);                                     current_setp++;                                     mlastmatch = exttype;                                     start = end;                                 }                             } else {                                 mlastmatch = -1;                             }                         }                         mlastdiff[k] = diff;                     }                     mlastdirections[k] = direction;                     mlastvalues[k] = v;                 }             }         }         log.d("sensorsteps", string.valueof(current_setp));         new handler().postdelayed(new runnable() {             public void run() {                 if(mstepsupdater!=null){                     mstepsupdater.updatestepcount(current_setp);                 }             }         }, 1000);       }       @override     public void onaccuracychanged(sensor sensor, int accuracy) {         // todo auto-generated method stub     } 

i want service return sensor data once in second, can store data in db. can tell me how can sensor data every second instead of multiples time in second.