[Demonstration 1]

[Buggy Method]
@DELETE
@Path("{id}")
public Response deleteUser(@PathParam("id") long userId, @Context HttpServletRequest httpServletRequest) {
    final HttpSession httpSession = httpServletRequest.getSession(false);
    if (httpSession != null) {
        //noinspection SynchronizationOnLocalVariableOrMethodParameter
        synchronized (httpSession) {
            try {
                final Object userIdFromSession = httpSession.getAttribute("user_id");
                if (userIdFromSession == null || !(userIdFromSession instanceof Long)) {
                    return Response.status(Response.Status.NOT_FOUND).entity(new BaseApiResponse()).build();
                }
                if (userId == (long) userId) {
                    userProfileService.deleteUser(userId);
                    authenticationService.deletePasswordForUser(userId);
                    httpSession.invalidate();
                    return Response.ok(new BaseApiResponse()).build();
                }
            } catch (IllegalStateException ignored) {
            }
        }
    }
    return Response.status(Response.Status.FORBIDDEN).entity(new BaseApiResponse()).build();
}

[Buggy Hunk]
if (userId == (long) userId) {

[Patch]
if (userId == (long) userIdFromSession) {

[Demonstration 2]

[Buggy Method]
@Override
public int read(long position, byte[] buffer, int offset, int len) throws IOException {
    int blockSize = _fileSystemBlockSize;
    try (Context context = _readTimer.time()) {
        long blockId = getBlockId(position);
        LOGGER.debug("read blockId {} len {} position {}", blockId, len, position);
        ByteBuffer byteBuffer = ByteBuffer.wrap(buffer, offset, len);
        List<ReadRequest> requests = createRequests(position, byteBuffer, blockSize);
        if (checkActiveWriter(requests)) {
            // commitActiveWriterIfNeeded(requests);
            readBlocks(requests);
        }
        _readMeter.mark(len);
        return len;
    } finally {
        // Nothing
    }
}

[Buggy Hunk]
if (checkActiveWriter(requests)) {

[Patch]
if (readActiveWriter(requests)) {

[Demonstration 3]

[Buggy Method]
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_form_transaction);
    this.dbHelper = new MoneyKeeperDBHelper(getApplicationContext(), this);
    dbHelper.getExpenditures();
    dbHelper.getIncomes();
    Toolbar toolbar = (Toolbar) findViewById(R.id.my_toolbar);
    setSupportActionBar(toolbar);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    amount = (TextInputEditText) findViewById(R.id.form_amount);
    comment = (TextInputEditText) findViewById(R.id.form_comment);
    division = (AppCompatSpinner) findViewById(R.id.division_spinner);
    inOrOut = (AppCompatSpinner) findViewById(R.id.in_or_out_spinner);
    inOrOut.setAdapter(new ArrayAdapter(this, R.layout.spinner_element, inOrOutArray));
    inOrOut.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            switch(i) {
                case 0:
                    division.setAdapter(inAdapter);
                    break;
                case 1:
                    division.setAdapter(exAdapter);
                    break;
            }
        }

        @Override
        public void onNothingSelected(AdapterView<?> adapterView) {
        }
    });
    AppCompatButton button = (AppCompatButton) findViewById(R.id.form_button);
    button.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View view) {
            MoneyKeeperDBHelper.Transaction t = new MoneyKeeperDBHelper.Transaction();
            t.amount = Integer.parseInt(amount.getText().toString());
            t.comment = comment.getText().toString();
            t.createdAt = MainActivity.getNow();
            if (inOrOut.getSelectedItemPosition() == 0) {
                t.division = MoneyKeeperDBHelper.INCOMES;
                t.divisionId = ((MoneyKeeperDBHelper.Income) division.getSelectedItem()).id;
            } else {
                t.division = MoneyKeeperDBHelper.EXPENDITURES;
                t.divisionId = ((MoneyKeeperDBHelper.Expenditure) division.getSelectedItem()).id;
            }
            dbHelper.insertTransaction(t);
            setResult(RESULT_OK);
            finish();
        }
    });
}

[Buggy Hunk]
t.createdAt = MainActivity.getNow();

[Patch]
t.createdAt = MainActivity.getyyyyMMdd();