构造函数的Java Spring参数0是必填项

Question

我正在学习Spring Framework,我得到了以下错误消息：

com.example.demo.AppUser.AppUserService中的构造函数的参数0需要类型为“com.example.demo.AppUser.AppUserRepository”的bean，但找不到该bean。

package com.example.demo.appuser;

import lombok.AllArgsConstructor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Service;

@Service
@AllArgsConstructor
public class AppUserService implements UserDetailsService {

    private final static String USER_NOT_FOUND_MSG =
            "user with email %s not found";

    @Autowired
    private AppUserRepository appUserRepository;


    @Override
    public UserDetails loadUserByUsername(String email)
            throws UsernameNotFoundException {
        return appUserRepository.findByEmail(email)
                .orElseThrow(() ->
                        new UsernameNotFoundException(
                                String.format(USER_NOT_FOUND_MSG, email)));
    }
}

这是我的AppUserRepository

package com.example.demo.appuser;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

import java.util.Optional;

@Repository
@Transactional(readOnly = true)
public interface AppUserRepository
        extends JpaRepository<AppUser, Long> {

    Optional<AppUser> findByEmail(String email);
}

如果有人知道问题出在哪里，请帮帮我

Answer 1

正如@Jesper的回答，您的AppUserRepository不在spring应用程序上下文中。请检查spring主类，并确保类上面有一个名为@EntityScan(${RepositoryPackagePrefix}）的注释。例如:@EntityScan（“com.example”）。