Instanz von ViewModel in Android kann nicht erstellt werden

Hallo, ich bin neu in Android und habe versucht, MVVM zu lernen, aber ich kann nicht herausfinden, warum ich den Fehler habe, dass keine Instanz der viewmodel-Klasse erstellt werden kann:

Dies sind die Fehler, die ich bekomme:

2020-06-29 12:30:26.293 15174-15174/com.carrot.roomdatabase E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.carrot.roomdatabase, PID: 15174
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.carrot.roomdatabase/com.carrot.roomdatabase.MainActivity}: java.lang.RuntimeException: Cannot create an instance of class com.carrot.roomdatabase.ViewModel
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3388)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3527)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2123)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7710)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
     Caused by: java.lang.RuntimeException: Cannot create an instance of class com.carrot.roomdatabase.ViewModel
        at androidx.lifecycle.ViewModelProvider$NewInstanceFactory.create(ViewModelProvider.java:221)
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:187)
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:150)
        at com.carrot.roomdatabase.MainActivity.onCreate(MainActivity.java:31)
        at android.app.Activity.performCreate(Activity.java:7820)
        at android.app.Activity.performCreate(Activity.java:7809)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1318)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3363)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3527) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2123) 
        at android.os.Handler.dispatchMessage(Handler.java:107) 
        at android.os.Looper.loop(Looper.java:214) 
        at android.app.ActivityThread.main(ActivityThread.java:7710) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950) 
     Caused by: java.lang.InstantiationException: java.lang.Class<com.carrot.roomdatabase.ViewModel> has no zero argument constructor
        at java.lang.Class.newInstance(Native Method)
        at androidx.lifecycle.ViewModelProvider$NewInstanceFactory.create(ViewModelProvider.java:219)
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:187) 
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:150) 
        at com.carrot.roomdatabase.MainActivity.onCreate(MainActivity.java:31) 
        at android.app.Activity.performCreate(Activity.java:7820) 
        at android.app.Activity.performCreate(Activity.java:7809) 
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1318) 
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3363) 
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3527) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2123) 
        at android.os.Handler.dispatchMessage(Handler.java:107) 
        at android.os.Looper.loop(Looper.java:214) 
        at android.app.ActivityThread.main(ActivityThread.java:7710) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950) 
2020-06-29 12:30:26.304 15174-15174/? I/Process: Sending signal. PID: 15174 SIG: 9

Unten sind meine Klassen

MainActivity.java-Klasse:

public class MainActivity extends AppCompatActivity {

    private RecyclerView recyclerView;
    private recycleViewAdapter adapter;
    private ViewModel viewModel;
    private List<NotesEntity> notesEntityList = new ArrayList<>();
    private FloatingActionButton btn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        viewModel = new ViewModelProvider(this).get(ViewModel.class);
        viewModel.getAllNotes().observe(this, new Observer<List<NotesEntity>>() {
            @Override
            public void onChanged(List<NotesEntity> notesEntities) {
                Toast.makeText(MainActivity.this, "onChanged", Toast.LENGTH_SHORT).show();
                adapter.notifyDataSetChanged();
            }
        });

        btn = findViewById(R.id.floatingActionButton);
        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(MainActivity.this , AddNote.class));
            }
        });
        init();
    }
    private void init(){
        adapter = new recycleViewAdapter(notesEntityList);
        recyclerView.setAdapter(adapter);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
    }
}

ViewModel.java-Klasse:

public class ViewModel extends AndroidViewModel {
    private Repository repository;
    private LiveData<List<NotesEntity>> allNotes;
    public ViewModel(@NonNull Application application) {
        super(application);
        repository = new Repository(application);
        allNotes = repository.getNotes();
    }

    public void insertThis(NotesEntity notesEntity){
        repository.Insert(notesEntity);
    }
    public void deleteThis(NotesEntity notesEntity){
        repository.Delete(notesEntity);
    }

    public LiveData<List<NotesEntity>> getAllNotes(){
        return allNotes;
    }
}

Kann mir bitte jemand helfen, herauszufinden, was ich falsch mache? Danke dir.