[Demonstration 1]

[Buggy Method]
public Finder constructFinder(Expression expression, MatchingMetaStateHolder matchingMetaStateHolder, ExecutionPlanContext executionPlanContext, List<VariableExpressionExecutor> variableExpressionExecutors, Map<String, EventTable> eventTableMap) {
    return OperatorParser.constructOperator(this.expiredEventChunk, expression, matchingMetaStateHolder, executionPlanContext, variableExpressionExecutors, eventTableMap);
}

[Buggy Hunk]
return OperatorParser.constructOperator(this.expiredEventChunk, expression, matchingMetaStateHolder, executionPlanContext, variableExpressionExecutors, eventTableMap);

[Patch]
return OperatorParser.constructOperator(this.internalWindowChunk, expression, matchingMetaStateHolder, executionPlanContext, variableExpressionExecutors, eventTableMap);

[Demonstration 2]

[Buggy Method]
public void actionlogin() {
    try {
        database = new Database();
        if (database.loginCheck(tfUsername.getText(), tfPassword.getText())) {
            primaryStage = (Stage) btLogin.getScene().getWindow();
            primaryStage.close();
            Lobby lobby = new Lobby(primaryStage, new User("Martijn"));
            System.out.println("User: " + tfUsername.getText() + " logged in!");
        } else {
            showPopupWindow("Invalid login combination!", "Ok");
            System.out.println("Logged in (no user)!");
        }
    } catch (SQLException | IOException ex) {
        Logger.getLogger(Login.class.getName()).log(Level.SEVERE, null, ex);
    } catch (IllegalArgumentException ex) {
        showPopupWindow("Field is empty!", "Ok");
    }
}

[Buggy Hunk]
Lobby lobby = new Lobby(primaryStage, new User("Martijn"));

[Patch]
Lobby lobby = new Lobby(primaryStage, database.getUser(tfUsername.getText()));

[Demonstration 3]

[Buggy Method]
public Lobby getLobby(User user) {
    for (Lobby lobby : lobbyList.values()) {
        for (User lobbyUser : lobby.getLobbyUsers()) {
            if (user.getId() == lobbyUser.getId()) {
                return lobby;
            }
        }
    }
    return null;
}

[Buggy Hunk]
for (User lobbyUser : lobby.getLobbyUsers()) {

[Patch]
for (User lobbyUser : lobby.getLobbyUsers().keySet()) {