java - Autowired @Service 并非在任何地方都为 null

Question

我知道有数十亿人对这个问题提出疑问，但我无法解决我的问题。我有 Spring + Hibernate 的应用程序。 Hibernate 有 2 个配置(用于客户数据库和管理数据库)。客户的 hibernate 支持使用数据库方法的 Multi-Tenancy 。我还使用 Spring Security。
这是我的租户 ID 解析类:

@Component
public class MyTenantIdentifierResolver implements CurrentTenantIdentifierResolver {

    @Autowired
    private UserService userService;

    public String resolveCurrentTenantIdentifier() {
        User u = (User) SecurityContextHolder.getContext().getAuthentication().getPrincipal();
        com.lspsystem.model.User us = userService.getByLogin(u.getUsername());
        return us.getCompany().getTenantId();
    }

    public boolean validateExistingCurrentSessions() {
        return true;
    }
}

这是我的用户服务:

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserDAO userDAO;

    public User get(Integer id) {
        return userDAO.get(id);
    }

    public boolean delete(Integer id) {
        return userDAO.delete(id);
    }

    public void update(User u) {
        userDAO.update(u);
    }

    public List<User> getAll(User u) {
        return userDAO.getAllUsers();
    }

    public User getByLogin(String login) {
        return userDAO.getByLogin(login);
    }
}

我的问题:为什么 MyTenantIdResolver 中的 UserService 始终为 null？但是，例如在下一类(来自安全性)中，它不会 null。

@Service
public class UserDetailsServiceImpl implements UserDetailsService {

    @Autowired
    private UserService userService;

    public User loadUserByUsername(String s) throws UsernameNotFoundException {
        com.lspsystem.model.User u = userService.getByLogin(s);
        return new User(u.getEmail(), u.getPassword(), true, true, true, true, getGrantedAuthorities(u));
    }

    @Autowired
    public UserDetailsServiceImpl(UserService userService) {
        this.userService = userService;
    }

    private List<GrantedAuthority> getGrantedAuthorities(com.lspsystem.model.User u) {
        List<GrantedAuthority> authorities = new ArrayList<GrantedAuthority>();
        return authorities;
    }
}

请注意，UserService 和 MyTenantIdResolver 属于不同的 hibernate 配置。

已更新
客户 hibernate 配置:

@Configuration
@EnableTransactionManagement
@PropertySource(value = {"classpath:customerHibernate.properties"})
public class RemoteDBHibernateConfig {

@Autowired
private Environment environment;

@Bean(name = "customerSessionFactory")
public SessionFactory sessionFactory() throws IOException{
    LocalSessionFactoryBean builder =
            new LocalSessionFactoryBean();
    builder.setDataSource(dataSource1());
    builder.setPackagesToScan("com.lspsystem.model");
    builder.setHibernateProperties(hibernateProperties());
    builder.afterPropertiesSet();

    return builder.getObject();
}

@Bean("defaultDS")
public DataSource dataSource1() {
    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName(environment.getRequiredProperty("jdbc.driverClassName"));
    dataSource.setUrl(environment.getRequiredProperty("jdbc.url"));
    dataSource.setUsername(environment.getRequiredProperty("jdbc.username"));
    dataSource.setPassword(environment.getRequiredProperty("jdbc.password"));
    return dataSource;
}

private Properties hibernateProperties() {
    Properties properties = new Properties();
    properties.put("hibernate.dialect", environment.getRequiredProperty("hibernate.dialect"));
    properties.put("hibernate.show_sql", environment.getRequiredProperty("hibernate.show_sql"));
    properties.put("hibernate.format_sql", environment.getRequiredProperty("hibernate.format_sql"));
    properties.put("hibernate.multiTenancy", environment.getRequiredProperty("hibernate.multiTenancy"));
    properties.put("hibernate.multi_tenant_connection_provider", environment.getRequiredProperty("hibernate.multi_tenant_connection_provider"));
    properties.put("hibernate.tenant_identifier_resolver", environment.getRequiredProperty("hibernate.tenant_identifier_resolver"));
    return properties;
}

@Bean
@Autowired
public HibernateTransactionManager transactionManager() throws IOException{
    HibernateTransactionManager txManager = new HibernateTransactionManager();
    txManager.setSessionFactory(sessionFactory());
    return txManager;
}}

管理 hibernate 配置:

@Configuration
@EnableTransactionManagement
@PropertySource(value = {"classpath:adminHibernate.properties"})
public class AdminDBHibernateConfig {

@Autowired
private Environment environment;

@Bean(name = "adminSessionFactory")
public SessionFactory sessionFactory() throws IOException {
    LocalSessionFactoryBean builder =
            new LocalSessionFactoryBean();
    builder.setDataSource(dataSource());
    builder.setPackagesToScan("com.lspsystem.model");
    builder.setHibernateProperties(hibernateProperties());
    builder.afterPropertiesSet();

    return builder.getObject();
}

@Bean
public DataSource dataSource() {
    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName(environment.getRequiredProperty("admin.jdbc.driverClassName"));
    dataSource.setUrl(environment.getRequiredProperty("admin.jdbc.url"));
    dataSource.setUsername(environment.getRequiredProperty("admin.jdbc.username"));
    dataSource.setPassword(environment.getRequiredProperty("admin.jdbc.password"));
    return dataSource;
}

private Properties hibernateProperties() {
    Properties properties = new Properties();
    properties.put("hibernate.dialect", environment.getRequiredProperty("admin.hibernate.dialect"));
    properties.put("hibernate.show_sql", environment.getRequiredProperty("admin.hibernate.show_sql"));
    properties.put("hibernate.format_sql", environment.getRequiredProperty("admin.hibernate.format_sql"));
    properties.put("hibernate.hbm2dll.auto", environment.getRequiredProperty("admin.hibernate.hbm2ddl.auto"));
    return properties;
}

@Bean
@Autowired
public HibernateTransactionManager transactionManager() throws IOException{
    HibernateTransactionManager txManager = new HibernateTransactionManager();
    txManager.setSessionFactory(sessionFactory());
    return txManager;
}}

网络应用配置:

@Configuration
@EnableWebMvc
@Import(SecurityConfiguration.class)
public class WebApplicationConfig extends WebMvcConfigurerAdapter{

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/resources/**").addResourceLocations("/resources/");
}

@Bean
public InternalResourceViewResolver viewResolver(){
    InternalResourceViewResolver view = new InternalResourceViewResolver();
    view.setViewClass(JstlView.class);
    view.setPrefix("/WEB-INF/jsp/");
    view.setSuffix(".jsp");
    return view;
}}

UserDAO，例如:

@Repository
public class UserDAOImpl implements UserDAO {

@Autowired
@Qualifier("adminSessionFactory")
private SessionFactory sessionFactory;

public com.lspsystem.model.User get(Integer id) {
    Session session = sessionFactory.openSession();
    User u = (User)session.load(User.class, id);
    return u;
}

public User getByLogin(String login) {
    Session session = sessionFactory.openSession();
    Query q = session.createQuery("SELECT u FROM User u WHERE u.email = :email");
    q.setParameter("email", login);
    User u = (User)q.list().get(0);
    return u;
}}

Answer 1

这不可能是真的! @Autowire 将强制该字段为非空。因此，唯一具有 userService=null 的情况是当 MyTenantIdentifierResolver 不是 spring bean 时!

将 MyTenantIdentifierResolver 实例设置为 spring-bean。