java - application crashing however logcat shows no Caused by: -

my application crashing while submitting on register page logcat not showing caused (i think might php server app making crash im unsure)

if there code link me show issue please comment , try , help.

04-24 10:36:43.910: e/androidruntime(8764): fatal exception: main 04-24 10:36:43.910: e/androidruntime(8764): java.lang.nullpointerexception 04-24 10:36:43.910: e/androidruntime(8764):     @ com.loggedin.login$processlogin.onpostexecute(login.java:173) 04-24 10:36:43.910: e/androidruntime(8764):     @ com.loggedin.login$processlogin.onpostexecute(login.java:1) 04-24 10:36:43.910: e/androidruntime(8764):     @ android.os.asynctask.finish(asynctask.java:631) 04-24 10:36:43.910: e/androidruntime(8764):     @ android.os.asynctask.access$600(asynctask.java:177) 04-24 10:36:43.910: e/androidruntime(8764):     @ android.os.asynctask$internalhandler.handlemessage(asynctask.java:644) 04-24 10:36:43.910: e/androidruntime(8764):     @ android.os.handler.dispatchmessage(handler.java:99) 04-24 10:36:43.910: e/androidruntime(8764):     @ android.os.looper.loop(looper.java:176) 04-24 10:36:43.910: e/androidruntime(8764):     @ android.app.activitythread.main(activitythread.java:5419) 04-24 10:36:43.910: e/androidruntime(8764):     @ java.lang.reflect.method.invokenative(native method) 04-24 10:36:43.910: e/androidruntime(8764):     @ java.lang.reflect.method.invoke(method.java:525) 04-24 10:36:43.910: e/androidruntime(8764):     @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:1046) 04-24 10:36:43.910: e/androidruntime(8764):     @ com.android.internal.os.zygoteinit.main(zygoteinit.java:862) 04-24 10:36:43.910: e/androidruntime(8764):     @ dalvik.system.nativestart.main(native method) 

login page code

import android.app.progressdialog; import android.content.context; import android.net.connectivitymanager; import android.net.networkinfo; import android.os.asynctask; import org.json.jsonexception; import org.json.jsonobject; import android.app.activity; import android.content.intent; import android.os.bundle; import android.view.view; import android.widget.button; import android.widget.edittext; import android.widget.textview; import android.widget.toast; import com.loggedin.internal.databasehandler;  import com.loggedin.internal.userfunctions; import java.io.ioexception; import java.net.httpurlconnection; import java.net.malformedurlexception; import java.net.url; public class login extends activity { button btnlogin; button registerbtn1; button passwordresetbtn; edittext inputusername; edittext inputpassword; private textview loginerrormsg; /**  * called when activity first created.  */  private static string key_success = "success";  private static string key_uid = "id";  private static string key_username = "username";  private static string key_firstname = "firstname";  private static string key_lastname = "lastname";  private static string key_email = "email";  private static string key_dob = "dob";  private static string key_created_at = "created_at";  @override  public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_login);     inputusername = (edittext) findviewbyid(r.id.username);     inputpassword = (edittext) findviewbyid(r.id.password);     registerbtn1 = (button) findviewbyid(r.id.registerbtn1);     btnlogin = (button) findviewbyid(r.id.loginbtn1);     passwordresetbtn = (button)findviewbyid(r.id.passwordresetbtn);     loginerrormsg = (textview) findviewbyid(r.id.loginerrormsg);     passwordresetbtn.setonclicklistener(new view.onclicklistener() {     public void onclick(view view) {     intent myintent = new intent(view.getcontext(), passwordreset.class);     startactivityforresult(myintent, 0);     finish();     }});     registerbtn1.setonclicklistener(new view.onclicklistener() {         public void onclick(view view) {             intent myintent = new intent(view.getcontext(), register.class);             startactivityforresult(myintent, 0);             finish();          }});  /**  * login button click event  * toast set alert when email , password field empty   **/     btnlogin.setonclicklistener(new view.onclicklistener() {         public void onclick(view view) {      if (  ( !inputusername.gettext().tostring().equals("")) && (   !inputpassword.gettext().tostring().equals("")) )             {                 internetasync(view);             }             else if ( ( !inputusername.gettext().tostring().equals("")) )             {                 toast.maketext(getapplicationcontext(),                         "password field empty", toast.length_short).show();             }             else if ( ( !inputpassword.gettext().tostring().equals("")) )             {                 toast.maketext(getapplicationcontext(),                         "username field empty", toast.length_short).show();             }             else             {                 toast.maketext(getapplicationcontext(),                         "username , password field empty", toast.length_short).show();             }         }     });  }  /**  * async task check whether internet connection working.  **/  private class internetcheck extends asynctask <string, string, boolean>    {     private progressdialog ndialog;     @override     protected void onpreexecute(){         super.onpreexecute();         ndialog = new progressdialog(login.this);         ndialog.settitle("checking network");         ndialog.setmessage("loading..");         ndialog.setindeterminate(false);         ndialog.setcancelable(true);         ndialog.show();     }     @override     protected boolean doinbackground(string... args){    /**    * gets current device state , checks working internet connection trying google.    **/         connectivitymanager cm = (connectivitymanager) getsystemservice(context.connectivity_service);         networkinfo netinfo = cm.getactivenetworkinfo();         if (netinfo != null && netinfo.isconnected()) {             try {                 url url = new url("http://www.google.com");                 httpurlconnection urlc = (httpurlconnection) url.openconnection();                 urlc.setconnecttimeout(3000);                 urlc.connect();                 if (urlc.getresponsecode() == 200) {                     return true;                 }             } catch (malformedurlexception e1) {                 // todo auto-generated catch block                 e1.printstacktrace();             } catch (ioexception e) {                 // todo auto-generated catch block                 e.printstacktrace();             }         }         return false;     }     @override     protected void onpostexecute(boolean th){         if(th == true){             ndialog.dismiss();             new processlogin().execute();         }         else{             ndialog.dismiss();             loginerrormsg.settext("error in network connection");         }     }   }  /**  * async task , send data sql database through json respone.  **/   private class processlogin extends asynctask <string, string, jsonobject> {     private progressdialog pdialog;     string username, password;     @override     protected void onpreexecute() {         super.onpreexecute();         inputusername = (edittext) findviewbyid(r.id.username);         inputpassword = (edittext) findviewbyid(r.id.password);         username = inputusername.gettext().tostring();         password = inputpassword.gettext().tostring();         pdialog = new progressdialog(login.this);         pdialog.settitle("contacting servers");         pdialog.setmessage("logging in ...");         pdialog.setindeterminate(false);         pdialog.setcancelable(true);         pdialog.show();     }     @override     protected jsonobject doinbackground(string... args) {         userfunctions userfunction = new userfunctions();         jsonobject json = userfunction.loginuser(username, password);         return json;     }     @override     protected void onpostexecute(jsonobject json) {         try {            if (json.getstring(key_success) != null) {                 string res = json.getstring(key_success);                 if(integer.parseint(res) == 1){                     pdialog.setmessage("loading user space");                     pdialog.settitle("getting data");                     databasehandler db = new databasehandler(getapplicationcontext());                     jsonobject json_user = json.getjsonobject("user");                     /**                      * clear previous data in sqlite database.                      **/                     userfunctions logout = new userfunctions();                     logout.logoutuser(getapplicationcontext());                      db.adduser(json_user.getstring(key_firstname),json_user.getstring(key_lastname),json_user.getstring(key_email),json_user.getstring(key_dob),json_user.getstring(key_username),json_user.getstring(key_uid));                    /**                     *if json array details stored in sqlite launches user panel.                     **/                     intent upanel = new intent(getapplicationcontext(), main.class);                     upanel.addflags(intent.flag_activity_clear_top);                     pdialog.dismiss();                     startactivity(upanel);                     /**                      * close login screen                      **/                     finish();                 }else{                     pdialog.dismiss();                     loginerrormsg.settext("incorrect username/password");                 }             }         } catch (jsonexception e) {             e.printstacktrace();         }    }  } 

verify if variable null in onpostexecute method on onpostexecute