JPA Query문 에러

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'todoController': Unsatisfied dependency expressed through field 'service': Error creating bean with name 'todoService': Unsatisfied dependency expressed through field 'repository': Error creating bean with name 'todoRepository' defined in com.example.demo.persistence.TodoRepository defined in @EnableJpaRepositories declared on JpaRepositoriesRegistrar.EnableJpaRepositoriesConfiguration: Could not create query for public abstract java.util.List com.example.demo.persistence.TodoRepository.findByUserIdQuery(java.lang.String); Reason: Validation failed for query for method public abstract java.util.List com.example.demo.persistence.TodoRepository.findByUserIdQuery(java.lang.String)

Validation failed for query

• NativeQuery = True 로 하면 됨 → 성공

JPQL이 아닌 SQL문을 직접 선언할 때 사용하는 옵션이라고 함….

findById 에러

JPA에서 기본 제공하는 findById 함수는 Optional 형태로 리턴이 됨 ( null값을 가지지 못하는 자료형이라고 함)

final Optional<TodoEntity> original = repository.findById(entity.getId());
        
        original.ifPresent(todo->{ // optional이 존재한다면...
            todo.setTitle(entity.getTitle());
            todo.setDone(entity.isDone());

            repository.save(todo);
        });

따라서 Optional 형태로 받아온 다음, ifPresent 함수를 이용해서 존재할 때만 값을 할당해준다!!

Ambiguous Mapping

Error creating bean with name 'requestMappingHandlerMapping' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Ambiguous mapping. Cannot map 'todoController' method

com.example.demo.controller.TodoController#createTodo(TodoDTO) to {[POST, GET] [/todo]}: There is already 'todoController' bean method com.example.demo.controller.TodoController#retrieveTodoList() mapped.