[Demonstration 1]

[Buggy Method]
@Override
public void start(Stage primaryStage) {
    // Create Layout
    Parent root = createLayout();
    Scene scene = new Scene(root, 425, 300);
    primaryStage.setTitle("Currency Calculator");
    primaryStage.setScene(scene);
    primaryStage.show();
}

[Buggy Hunk]
Parent root = createLayout();

[Patch]
Parent root = CurrencyCalculatorFX.createLayout();

[Demonstration 2]

[Buggy Method]
@RequestMapping(value = "/roles", method = RequestMethod.POST)
public int addRole(@RequestBody RoleEntity roleEntity) {
    return roleService.addRole(roleEntity);
}

[Buggy Hunk]
public int addRole(@RequestBody RoleEntity roleEntity){

[Patch]
public RoleEntity addRole(@RequestBody RoleEntity roleEntity){

[Demonstration 3]

[Buggy Method]
public Error isUsernameAvailable(String username) {
    varSQL = "SELECT * " + "FROM Users " + "WHERE User = " + "'" + username.toLowerCase() + "'";
    try {
        if (!queryDatabase(varSQL).absolute(1)) {
            return Error.USERNAME_NOT_AVAILABLE;
        } else {
            return Error.NO_ERROR;
        }
    } catch (SQLException e) {
        return Error.DATABASE_ERROR;
    }
}

[Buggy Hunk]
if(!queryDatabase(varSQL).absolute(1)){return Error.USERNAME_NOT_AVAILABLE;}

[Patch]
if(queryDatabase(varSQL).absolute(1)){System.out.println("in the error");return Error.USERNAME_NOT_AVAILABLE;}