Can't make instance from java class -

i write code msn application , , application connection server asp.net code run in computer , when run code in other computer giving me runtime error in line

new signinperson(s1,s2); 

error:

could not find class 'com.example.hello.signinperson' referenced method com.example.hello.mainactivity.gotoprofileactivity 

code:

public class mainactivity extends activity {     public final string url="http://10.0.2.2:47102/projecttwo/service.asmx";     public final string namespace="http://tempuri.org/";     public final string method= "signin";     public final string action = "http://tempuri.org/signin";     private edittext edittextemail;     private edittext edittextpass;     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);     }     public void gotosignupactivity (view v)     {         intent signupact = new intent("com.example.hello.signupactivity");         startactivity(intent.createchooser(signupact, "choose application"));     }     public void gotoprofileactivity (view v)     {         edittextemail = (edittext) findviewbyid(r.id.edit_text_email);         edittextpass = (edittext) findviewbyid(r.id.edit_text_pass);         if (isemptyedittext(edittextemail) | isemptyedittext(edittextpass))          {             showdialog(0);         }         else         {             string s1 = edittextemail.gettext().tostring().trim();             string s2 = edittextpass.gettext().tostring().trim();             signinperson siperson = new signinperson(s1,s2);             soapobject req = new soapobject(namespace, method);             propertyinfo p = new propertyinfo();             p.setname("siperson");             p.setvalue(siperson);             p.settype(siperson.getclass());             req.addproperty(p);             soapserializationenvelope env = new soapserializationenvelope(soapserializationenvelope.ver11);             env.dotnet = true;              env.setoutputsoapobject(req);             env.addmapping(namespace, "signinperson", new signinperson().getclass());             httptransportse ahttp = new httptransportse(url);             soapobject res = null;             try             {                 ahttp.call(action, env);                 res = (soapobject) env.getresponse();             }             catch (exception ex)             {                 ex.printstacktrace();             }             if (integer.parseint(res.getproperty(0).tostring())==0)             {                 showdialog(1);             }             else             {                 siperson.person_id = integer.parseint(res.getproperty(0).tostring());                 siperson.f_name = res.getpropertyasstring(1).tostring();                 siperson.l_name = res.getpropertyasstring(2).tostring();                 siperson.e_mail = res.getpropertyasstring(3).tostring();                 siperson.password = res.getpropertyasstring(4).tostring();                 intent profileact = new intent("com.example.hello.profileactivity");                 profileact.putextra("recivelogin", siperson);                 startactivity(intent.createchooser(profileact, "choose application"));             }         }     }     public boolean isemptyedittext (edittext et)     {         boolean isempty = true;         if (et.gettext().tostring().trim().length() > 0)         {             isempty = false;         }         return isempty;     }     @override     protected dialog oncreatedialog(int id)     {         switch (id)         {         case 0:             dialog enterbothdialog = new dialog(this);             enterbothdialog.settitle("please enter both e-mail / password");             return enterbothdialog;         case 1:             dialog invalidempass = new dialog(this);             invalidempass.settitle("invalid email / password");             return invalidempass;         }         return null;     } } 

and signinperson

public class signinperson implements kvmserializable, serializable {     public int person_id;     public string f_name;     public string l_name;     public string e_mail;     public string password;     public signinperson ()      {     }     public signinperson (int id, string fname, string lname, string email, string pass)     {         person_id = id;         f_name = fname;         l_name = lname;         e_mail = email;         password = pass;     }      public signinperson (string email, string pass)     {         person_id = 0;         f_name = "";         l_name = "";     }     @override     public object getproperty(int arg0) {         // todo auto-generated method stub         switch (arg0)         {         case 0:             return person_id;         case 1:             return f_name;         case 2:             return l_name;         case 3:             return e_mail;         case 4:             return password;         }         return null;     }      @override     public int getpropertycount() {         // todo auto-generated method stub         return 5;     }      @override     public void getpropertyinfo(int arg0, hashtable arg1, propertyinfo arg2) {         // todo auto-generated method stub         switch (arg0)         {         case 0:             arg2.type = propertyinfo.integer_class;             arg2.name = "person_id";             break;         case 1:             arg2.type = propertyinfo.string_class;             arg2.name = "f_name";             break;         case 2:             arg2.type = propertyinfo.string_class;             arg2.name = "l_name";             break;         case 3:             arg2.type = propertyinfo.string_class;             arg2.name = "e_mail";             break;         case 4:             arg2.type = propertyinfo.string_class;             arg2.name = "password";             break;             default:break;         }     }      @override     public void setproperty(int arg0, object arg1) {         // todo auto-generated method stub         switch (arg0)         {         case 0:             person_id = integer.parseint(arg1.tostring());             break;         case 1:             f_name = arg1.tostring();             break;         case 2:             l_name = arg1.tostring();             break;         case 3:             e_mail = arg1.tostring();             break;         case 4:             password = arg1.tostring();             break;             default:break;         }     }  } 

but when delete implements signinperson , override

public class signinperson{     /**      *       */     private static final long serialversionuid = 1l;     public int person_id;     public string f_name;     public string l_name;     public string e_mail;     public string password;     public signinperson ()      {     }     public signinperson (int id, string fname, string lname, string email, string pass)     {         person_id = id;         f_name = fname;         l_name = lname;         e_mail = email;         password = pass;     }      public signinperson (string email, string pass)     {         person_id = 0;         f_name = "";         l_name = "";     } } 

it make new signinperson , don't give me run time

i trying found problem long time can't find wrong

please , can me

because must send application in morning

you should change line:

signinperson siperson = null; new signinperson(s1,s2); 

to:

signinperson siperson = new signinperson(s1,s2);