Advice with strange NullPointerException

Question

Here is my class. I have a problem. I fill all data correctly and when I'm making Toast i've got NullPointerExeption. I don't know why. I'm making all inputs in EditTexts. Can anyone see what I'm doing wrong?

public class Wyslij extends Activity {

    protected final int TIMEOUT_MILLISEC = 30;
    EditText et_nazwa;
    EditText et_nip;
    EditText et_adres;
    ImageButton ib_wyslij;


    final TowarZamowienie tz = new TowarZamowienie();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.wyslij);

        et_nazwa = (EditText) findViewById(R.id.et_nazwa);
        et_nip = (EditText) findViewById(R.id.et_nip);
        et_adres = (EditText) findViewById(R.id.et_adres);
        ib_wyslij = (ImageButton) findViewById(R.id.ib_wyslij);

        String nazwa_firmy = et_nazwa.getText().toString();
        String nip_firmowy = et_nip.getText().toString();
        String adres_firmy = et_adres.getText().toString();

        final Zamowienie zam = new Zamowienie();

        if (nazwa_firmy != null && !nazwa_firmy.equalsIgnoreCase("")) {

            zam.klient.setNazwa(et_nazwa.getText().toString());
        }

        if (nip_firmowy != null && !nip_firmowy.equalsIgnoreCase("")) {

            zam.klient.setNip(et_nip.getText().toString());
        }

        if (adres_firmy != null && !adres_firmy.equalsIgnoreCase("")) {

            zam.klient.setAdres(et_adres.getText().toString());
        }

        final String suma_zamowienia = podaj_sume(TowarZamowienie.towary_zamowione);

        zam.setSuma(suma_zamowienia);

        zam.setZam_id(MainActivity.nr_zamowienia);

        MainActivity.nr_zamowienia++;

        tz.setZam_id(zam.getZam_id());

        final String[] s = new String[TowarZamowienie.towary_zamowione.size()];

        for (int i = 0; i < TowarZamowienie.towary_zamowione.size(); i++) {

            s[i] = TowarZamowienie.towary_zamowione.get(i).getTows_id();
        }

        ib_wyslij.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

                // new

                Toast.makeText(getApplication(),
                        zam.klient.getNazwa()+ " "+zam.klient.getNip()+" "+zam.klient.getAdres().toString(), Toast.LENGTH_LONG)
                        .show();

            }
        });

    }



    private String podaj_sume(ArrayList<Towar> l) {
        int suma = 0;
        for (int i = 0; i < l.size(); i++) {
            suma += l.get(i).Tow_ilosc * l.get(i).Tow_cena;
        }

        return String.valueOf(suma);
    }

}

My LogCat errors:

02-11 23:08:59.546: W/dalvikvm(17234): threadid=1: thread exiting with uncaught exception (group=0x40be71f8) 02-11 23:08:59.554: E/AndroidRuntime(17234): FATAL EXCEPTION: main 02-11 23:08:59.554: E/AndroidRuntime(17234): java.lang.NullPointerException 02-11 23:08:59.554: E/AndroidRuntime(17234): at com.example.inzynierka.Wyslij$1.onClick(Wyslij.java:110) 02-11 23:08:59.554: E/AndroidRuntime(17234): at android.view.View.performClick(View.java:3558) 02-11 23:08:59.554: E/AndroidRuntime(17234): at android.view.View$PerformClick.run(View.java:14152) 02-11 23:08:59.554: E/AndroidRuntime(17234): at android.os.Handler.handleCallback(Handler.java:605) 02-11 23:08:59.554: E/AndroidRuntime(17234): at android.os.Handler.dispatchMessage(Handler.java:92) 02-11 23:08:59.554: E/AndroidRuntime(17234): at android.os.Looper.loop(Looper.java:137) 02-11 23:08:59.554: E/AndroidRuntime(17234): at android.app.ActivityThread.main(ActivityThread.java:4514) 02-11 23:08:59.554: E/AndroidRuntime(17234): at java.lang.reflect.Method.invokeNative(Native Method) 02-11 23:08:59.554: E/AndroidRuntime(17234): at java.lang.reflect.Method.invoke(Method.java:511) 02-11 23:08:59.554: E/AndroidRuntime(17234): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790) 02-11 23:08:59.554: E/AndroidRuntime(17234): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557) 02-11 23:08:59.554: E/AndroidRuntime(17234): at dalvik.system.NativeStart.main(Native Method)

Zamowienie.class public class Zamowienie {

public int id;

public int zam_id;

public String suma;


public Klient klient;

public Zamowienie(int id, String suma, Klient klient) {
    super();
    this.zam_id = id;
    this.suma = suma;
    this.klient = klient;
}
public Zamowienie() {
    super();
}
public int getId() {
    return id;
}
public int getZam_id() {
    return zam_id;
}
public void setZam_id(int zam_id) {
    this.zam_id = zam_id;
}
public void setId(int id) {
    this.id = id;
}
public String getSuma() {
    return suma;
}
public void setSuma(String suma) {
    this.suma = suma;
}

}

Answer 1

In onCreate() you do this:

final Zamowienie zam = new Zamowienie();

and then you try to access zam.klient

but you never set zam.klient to anything, so it is null.

Answer 2

You are referencing the klient variable of class Zamownienie. The variable is not set. You are calling the no-arg constructor of Zamownienie which means klient is set to null.

Please consider using standard Java naming conventions as well as NOT giving class variables public scope.

HTH

Answer 3

Try by putting this in OnClick:

Toast.makeText(Wyslij.this,
                        zam.klient.getNazwa()+ " "+zam.klient.getNip()+" "+zam.klient.getAdres().toString(), Toast.LENGTH_LONG)
                        .show();