UserService.java

package com.example.oauth2.service;

import com.example.oauth2.entity.User;
import com.example.oauth2.repository.UserRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service
@RequiredArgsConstructor
@Transactional(readOnly = true)
public class UserService {
    
    private final UserRepository userRepository;
    
    public User findByEmail(String email) {
        return userRepository.findByEmail(email)
                .orElseThrow(() -> new RuntimeException("사용자를 찾을 수 없습니다: " + email));
    }
    
    public User findById(Long id) {
        return userRepository.findById(id)
                .orElseThrow(() -> new RuntimeException("사용자를 찾을 수 없습니다: " + id));
    }
    
    public boolean existsByEmail(String email) {
        return userRepository.existsByEmail(email);
    }
}