Вылетает при нажатии на кнопку создания заметки

Вот ошибки:

E/AndroidRuntime: FATAL EXCEPTION: main
Process: ru.n1ghtlightsapp.myapplication, PID: 14124
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{ru.n1ghtlightsapp.myapplication/ru.n1ghtlightsapp.myapplication.editNote}: java.lang.IllegalAccessException: java.lang.Class<ru.n1ghtlightsapp.myapplication.editNote> is not accessible from java.lang.Class<android.app.Instrumentation>
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2679)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
    at android.app.ActivityThread.-wrap11(Unknown Source:0)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:164)
    at android.app.ActivityThread.main(ActivityThread.java:6494)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
 Caused by: java.lang.IllegalAccessException: java.lang.Class<ru.n1ghtlightsapp.myapplication.editNote> is not accessible from java.lang.Class<android.app.Instrumentation>
    at java.lang.Class.newInstance(Native Method)
    at android.app.Instrumentation.newActivity(Instrumentation.java:1174)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2669)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) 
    at android.app.ActivityThread.-wrap11(Unknown Source:0) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:164) 
    at android.app.ActivityThread.main(ActivityThread.java:6494) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
E/AndroidRuntime: FATAL EXCEPTION: main
Process: ru.n1ghtlightsapp.myapplication, PID: 14177
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{ru.n1ghtlightsapp.myapplication/ru.n1ghtlightsapp.myapplication.editNote}: java.lang.IllegalAccessException: java.lang.Class<ru.n1ghtlightsapp.myapplication.editNote> is not accessible from java.lang.Class<android.app.Instrumentation>
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2679)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
    at android.app.ActivityThread.-wrap11(Unknown Source:0)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:164)
    at android.app.ActivityThread.main(ActivityThread.java:6494)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
 Caused by: java.lang.IllegalAccessException: java.lang.Class<ru.n1ghtlightsapp.myapplication.editNote> is not accessible from java.lang.Class<android.app.Instrumentation>
    at java.lang.Class.newInstance(Native Method)
    at android.app.Instrumentation.newActivity(Instrumentation.java:1174)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2669)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) 
    at android.app.ActivityThread.-wrap11(Unknown Source:0) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:164) 
    at android.app.ActivityThread.main(ActivityThread.java:6494) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807) 

Код из MainActivity:

public class MainActivity extends AppCompatActivity {

static ArrayList<String> notes = new ArrayList<>();
static ArrayAdapter arrayAdapter;

@Override
public boolean onCreateOptionsMenu(Menu menu) {

    MenuInflater menuInflater = getMenuInflater();
    menuInflater.inflate(R.menu.note_add, menu);

    return super.onCreateOptionsMenu(menu);
}

@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item) {
    super.onOptionsItemSelected(item);

    if (item.getItemId() == R.id.add_note) {

        // Going from MainActivity to NotesEditorActivity
        Intent intent = new Intent(getApplicationContext(), editNote.class);
        startActivity(intent);
        return true;
    }

    return false;
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    ListView listView = findViewById(R.id.listView);
    SharedPreferences sharedPreferences = getApplicationContext().getSharedPreferences("com.example.notes", Context.MODE_PRIVATE);
    HashSet<String> set = (HashSet<String>) sharedPreferences.getStringSet("notes", null);

    if (set == null) {

        notes.add("Example note");
    } else {
        notes = new ArrayList(set);
    }

    // Using custom listView Provided by Android Studio
    arrayAdapter = new ArrayAdapter(this, android.R.layout.simple_expandable_list_item_1, notes);

    listView.setAdapter(arrayAdapter);

    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {

            // Going from MainActivity to NotesEditorActivity
            Intent intent = new Intent(getApplicationContext(), editNote.class);
            intent.putExtra("noteId", i);
            startActivity(intent);

        }
    });

    listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
        @Override
        public boolean onItemLongClick(AdapterView<?> adapterView, View view, int i, long l) {

            final int itemToDelete = i;
            // To delete the data from the App
            new AlertDialog.Builder(MainActivity.this)
                    .setIcon(android.R.drawable.ic_dialog_alert)
                    .setTitle("Вы уверены?")
                    .setMessage("Вы хотите удалить данную заметку?")
                    .setPositiveButton("Да", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {
                            notes.remove(itemToDelete);
                            arrayAdapter.notifyDataSetChanged();
                            SharedPreferences sharedPreferences = getApplicationContext().getSharedPreferences("com.example.notes", Context.MODE_PRIVATE);
                            HashSet<String> set = new HashSet(MainActivity.notes);
                            sharedPreferences.edit().putStringSet("notes", set).apply();
                        }
                    }).setNegativeButton("Нет", null).show();
            return true;
        }
    });
}

}