java - Jersey + Hibernate 将 SessionFactory 注入(inject) DAO

Question

我有一个 jax-rs/jersey Rest 应用程序，它使用 Hibernate 5.2 作为 orm。还有一个 spring 过滤器使用 token 处理身份验证。一切都运行得很好，但有一个小问题。每个 dao 对象都像这样在构造时创建自己的 session 工厂。

public abstract class BaseDAO<T> {

protected SessionFactory sessionFactory = getSessionFactory();
protected final Validator validator = getValidator();

protected SessionFactory getSessionFactory() {
    try {
        return (SessionFactory) new Configuration().configure().buildSessionFactory();
    } catch (Exception e) {
        throw new IllegalStateException("Could not locate SessionFactory in JNDI");
    }
}

protected Validator getValidator() {
    ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
    return factory.getValidator();
}

@SuppressWarnings({"hiding", "unchecked"})  
public <T> T save(final T o) {
    Session session = sessionFactory.getCurrentSession();
    Transaction tx = session.beginTransaction();
    T savedObj = (T) session.save(o);
    tx.commit();    
    session.close();        
    return savedObj;
}

public void delete(final Object object) {
    Session session = sessionFactory.getCurrentSession();
    Transaction tx = session.beginTransaction();
    session.delete(object);
    tx.commit();        
    session.close();        
}

@SuppressWarnings("hiding")     
public <T> T get(final Class<T> type, final int id) {
    Session session = sessionFactory.getCurrentSession();
    Transaction tx = session.beginTransaction();    
    T obj = session.get(type, id);
    tx.commit();    
    session.close();
    return obj;
}

@SuppressWarnings({"hiding", "unchecked"})
public <T> T merge(final T o) {
    Session session = sessionFactory.getCurrentSession();
    Transaction tx = session.beginTransaction();
    T obj = (T) session.merge(o);
    tx.commit();    
    session.close();        
    return obj;
}

@SuppressWarnings("hiding") 
public <T> void saveOrUpdate(final T o) {
    Session session = sessionFactory.getCurrentSession();
    Transaction tx = session.beginTransaction();
    session.saveOrUpdate(o);
    tx.commit();    
    session.close();        
}

@SuppressWarnings({ "hiding", "deprecation", "unchecked" }) 
public <T> List<T> getAll(final Class<T> type) {
    final Session session = sessionFactory.getCurrentSession();
    Transaction tx = session.beginTransaction();
    final Criteria crit = session.createCriteria(type);
    List<T> results = crit.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY).list();
    tx.commit();    
    session.close();        
    return results;
}

@SuppressWarnings({ "hiding", "deprecation", "unchecked" })
public <T> List<T> findByExample(final Class<T> type, T instance) {
    try {
        Session session = sessionFactory.getCurrentSession();
        Transaction tx = session.beginTransaction();
        List<T> results = session
                .createCriteria(type)
                .add(Example.create(instance))
                .setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY)
                .list();
        tx.commit();
        session.close();            
        return results;
    } catch (RuntimeException re) {
        //log.error("find by example failed", re);
        throw re;
    }
}

这是一个问题，因为如果您创建多个 dao 对象，您很快就会耗尽连接，即使我在每次 dao 调用后调用 session.close() 也是如此。对资源进行过多调用后，我的小型数据库实例提示连接过多。我立即想到的是 session 工厂需要由 Jersey 管理。所以我尝试像这样使用工厂绑定(bind)器:

public class HibernateSessionFactory implements Factory<SessionFactory> {

    protected SessionFactory sessionFactory;

    @Override
    public void dispose(SessionFactory arg0) {
        sessionFactory.close();
    }

    @Override
    public SessionFactory provide() {
        try {
            sessionFactory = (SessionFactory) new Configuration().configure().buildSessionFactory();
            return sessionFactory;
        } catch (Exception e) {
            throw new IllegalStateException("Could not locate SessionFactory     in JNDI");
        }       
    }
}

在资源配置中:

    register(new AbstractBinder() {
        @Override
        protected void configure() {
            bindFactory(HibernateSessionFactory.class).to(SessionFactory.class);
        }
    });

并将 BaseDAO 更改为此

@Inject
protected SessionFactory sessionFactory 

它似乎不起作用 - session 工厂始终为空。另一个问题是 Spring 过滤器不能使用 Jersey 注入(inject)。过滤器的配置如下。

@Configuration
@EnableWebSecurity
@EnableGlobalMethodSecurity(prePostEnabled = true, securedEnabled = true)
@Order(2)
public class SpringSecurityConfig extends WebSecurityConfigurerAdapter {

    private final com.renewedvoices.security.UserService userService;
    private final TokenAuthenticationService tokenAuthenticationService;
    private final SessionFactory sessionFactory;

    public SpringSecurityConfig() {
        super(true);
        this.userService = new UserService();
        this.tokenAuthenticationService = new     TokenAuthenticationService("tooManySecrets", userService);
        this.sessionFactory = createSessionFactory();
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
            // Custom Token based authentication based on the header previously given to the client     
            http
                .addFilterBefore(new StatelessAuthenticationFilter(tokenAuthenticationService),
                    UsernamePasswordAuthenticationFilter.class)         
                .authorizeRequests()
                .antMatchers("/rest/auth/**").permitAll()
                .antMatchers(HttpMethod.OPTIONS).permitAll()
                .anyRequest().authenticated()
                .and()
                .exceptionHandling().and()
                .anonymous().and()
                .servletApi().and()
                .headers().cacheControl();

    }

    private SessionFactory createSessionFactory() {
        try {
            return (SessionFactory) new org.hibernate.cfg.Configuration().configure().buildSessionFactory();
        } catch (Exception e) {
            throw new IllegalStateException("Could not locate SessionFactory in JNDI");
        }               
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(userDetailsService()).passwordEncoder(new     BCryptPasswordEncoder());
    }

    @Bean
    @Override
    public AuthenticationManager authenticationManagerBean() throws Exception {
        return super.authenticationManagerBean();
    }

    @Bean
    @Override
    public UserService userDetailsService() {
        return userService;
    }

    @Bean
    public TokenAuthenticationService tokenAuthenticationService() {
       return tokenAuthenticationService;
    }

    @Bean
    public SerssionFactory sessionFactory() {
       return sessionFactory;
    }
}

无论我在BaseDao中使用@Autowired还是@Inject，sessionFactory总是为null。我无法切换到纯粹的 Spring 。有什么方法可以让这个 sessionFactory 工作吗？这是在休息服务中处理 session 工厂的最佳方法还是有更好的方法不对每个请求打开新 session ？我找到的几乎所有答案都是仅限 Spring 的解决方案。任何帮助是极大的赞赏。

Answer 1

继续我上面的评论

You need to make the DAO a Spring bean so that it can be injected into Spring components. Then for Jersey you need to integrate Jersey to use Spring components so you can inject into Jersey. Have a look at this post.

所以您需要做的就是使 DAO 成为 Spring Bean。你可以这样做

@Configuration
public class DataConfiguration {
    @Bean
    public MyDao myDao() {
        return new MyDao();
    }
}

然后在您的 AbstractSecurityWebApplicationInitializer 中，您需要添加配置类，并覆盖 contextConfigLocation 属性，以便 Jersey 不会尝试创建 ContextLoaderListener。这已经由 Spring Security 创建了

@Order(1)
public class DemoSecurityWebApplicationInitializer
        extends AbstractSecurityWebApplicationInitializer {

    public DemoSecurityWebApplicationInitializer() {
        super(DataConfiguration.class, SecurityConfig.class);
    }

    @Override
    public void afterSpringSecurityFilterChain(ServletContext servletContext) {
        // Set the Jersey used property to it won't load a ContextLoaderListener
        servletContext.setInitParameter("contextConfigLocation", "NOOP");
    }
}

您需要做的最后一件事是添加 jersey-spring3 依赖项。这是 Jersey 依赖项，允许它与 Spring 组件集成(仅 Spring 到 Jersey，而不是 Jersey 到 Spring)。

<dependency>
    <groupId>org.glassfish.jersey.ext</groupId>
    <artifactId>jersey-spring3</artifactId>
    <exclusions>
       <!-- exclude Spring 3 if you want to use Spring 4 -->
    </exclusions>
<dependency>

请参阅 this GitHub project 中的完整示例。