java android studio GSON

Question

witam mam problem wydaje mi się że z przekazaniem danych, lecz nie wiem gdzie jest błąd

komunikat: java.lang.IllegalArgumentException: class com.example.pam3.Person declares multiple JSON fields named mLifecycleRegistry

wycinek z Main 

 protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        Locale locale = new Locale("PL");
        Locale.setDefault(locale);
        Configuration config = new Configuration();
        config.locale = locale;
        getApplicationContext().getResources().updateConfiguration(config, null);
        setContentView(R.layout.activity_main);
        firstname = (EditText) findViewById(R.id.imie);
        lastname = (EditText) findViewById(R.id.nazwisko);
        birthdate = (TextView) findViewById(R.id.dataurodzenia);
        street = (EditText) findViewById(R.id.ulica);
        dnumber = (EditText) findViewById(R.id.numerd);
        mnumber = (EditText) findViewById(R.id.numerm);
        city = (EditText) findViewById(R.id.miasto);
        pcode = (EditText) findViewById(R.id.kod);
        male = (RadioButton) findViewById(R.id.mezczyzna);
        female = (RadioButton) findViewById(R.id.kobieta);
        swimming = (CheckBox) findViewById(R.id.plywanie);
        basketball = (CheckBox) findViewById(R.id.koszykowka);
        horseriding = (CheckBox) findViewById(R.id.jazdakonna);
        jogging = (CheckBox) findViewById(R.id.bieganie);
        soccer = (CheckBox) findViewById(R.id.pilkanozna);
        volleyball = (CheckBox) findViewById(R.id.siatkowka);
        send = (Button) findViewById(R.id.wyslij);
        clear = (Button) findViewById(R.id.wyczysc);

        sex = new ArrayList<RadioButton>();
        sex.add(male);
        sex.add(female);
        activities = new ArrayList<CheckBox>();
        activities.add(swimming);
        activities.add(jogging);
        activities.add(horseriding);
        activities.add(basketball);
        activities.add(volleyball);
        activities.add(soccer);

        clear.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                clear_all();
                }
            });
            birthdate.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    final Calendar cldr = Calendar.getInstance();
                    int day = cldr.get(Calendar.DAY_OF_MONTH);
                    int month = cldr.get(Calendar.MONTH);
                    int year = cldr.get(Calendar.YEAR);
                    picker = new DatePickerDialog(MainActivity.this,
                            new DatePickerDialog.OnDateSetListener() {
                                @Override
                                public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
                                    birthdate.setText(dayOfMonth + "." + (monthOfYear + 1) + "." + year);
                                }
                            }, year, month, day);
                    picker.show();
                }
            });

            send.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Person person = new Person(
                            firstname.getText().toString(),
                            lastname.getText().toString(),
                            male.isChecked(),
                            city.getText().toString(),
                            street.getText().toString(),
                            dnumber.getText().toString(),
                            mnumber.getText().toString(),
                            pcode.getText().toString(),
                            birthdate.getText().toString()
                            );
                    for (CheckBox c : activities) {
                        if (c.isChecked()) {
                            person.AddActivity(c.getText().toString());
                        }
                    }
                    StartSummary(person);
                }
            });
        }
        public void StartSummary(Person p){
            Intent intent = new Intent(MainActivity.this,SummaryActivity.class);
            Gson gson = new Gson();
            intent.putExtra("person", gson.toJson(p));
            this.startActivity(intent);
        }

summary activity

public class SummaryActivity extends AppCompatActivity {
    TextView summary;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_summary);
        summary = (TextView)findViewById(R.id.summary);
        Gson gson = new Gson();
        String strobj = getIntent().getStringExtra("person");
        Person person = gson.fromJson(strobj, Person.class);
        summary.setText(person.toString());
    }

Person

public class Person extends AppCompatActivity {
    public String firstname;
    public String lastname;
    public boolean male;
    public String city;
    public String street;
    public String dnumber;
    public String mnumber;
    public String pcode;
    public String birthdate;
    public List<String> activities = new ArrayList<String>();


    public Person(String firstname, String lastname, boolean male, String city, String street, String dnumber, String mnumber, String pcode, String birthdate) {
        this.firstname = firstname;
        this.lastname = lastname;
        this.male = male;
        this.city = city;
        this.street = street;
        this.dnumber = dnumber;
        this.mnumber = mnumber;
        this.pcode = pcode;
        this.birthdate = birthdate;

    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    public void AddActivity(String toString) {
        activities.add(toString);
    }
}

 

Answer 1

 String strobj = getIntent().getStringExtra("person");
  Person person = gson.fromJson(strobj, Person.class);

jak wygląda twój strobj ?? Problemem jest zdeserializacja obiektu który jest w postaci JSON do postaci Person.class, gdyż dla parsera są niejednoznaczne pola (albo jest ich za dużo, albo mają niepoprawną nazwe, albo są niepoprawne ogółem np w wartości klucz:wartość)