Question

我一直在关注本教程： http://www.scribd.com/doc/25244173/Java-Struts-Spring-Hibernate-Tutorial 设置（前面描述）与教程文件一起正常工作，但是当我做了更改 - 删除/更新操作时就不会发生。没有错误或怪癖，它完全无视我！至于检索数据 - 一切都很完美......

几乎所有来自tut的文件都是相同的，有这些差异;本教程使用服务文件：

Services.java

package services;

import org.springframework.transaction.annotation.Transactional;
import org.hibernate.SessionFactory;
import org.hibernate.Session;
import data.*;
import java.util.List;

// This class is the business services tier in the application.
// @Transactional is needed so that a Hibernate transaction is set up,
//  otherwise updates won't have an affect
@Transactional
public class Services {
    // So Spring can inject the session factory
    SessionFactory sessionFactory;
    public void setSessionFactory(SessionFactory value) {
        sessionFactory = value;
    }

    // Shortcut for sessionFactory.getCurrentSession()
    public Session sess() {
        return sessionFactory.getCurrentSession();
    }

    public Event getEventById(long id) {
        return (Event) sess().load(Event.class, id);
    }

    public Person getPersonById(long id) {
        return (Person) sess().load(Person.class, id);
    }

    public void deleteEventById(long id) {
        sess().delete(getEventById(id));
    }

    public void deletePersonById(long id) {
        sess().delete(getPersonById(id));
    }

    public void createEvent(String name) {
        Event theEvent = new Event();
        theEvent.setName(name);
        sess().save(theEvent);
    }

    public void createPerson(String name) {
        Person p = new Person();
        p.setName(name);
        sess().save(p);
    }

    @SuppressWarnings("unchecked")
    public List getEvents() {
        return sess().createQuery("from Event").list();
    }

    @SuppressWarnings("unchecked")
    public List getPeople() {
        return sess().createQuery("from Person").list();
    }

    public void removePersonFromEvent(int personId, int eventId) {
        getEventById(eventId).getPeople().remove(getPersonById(personId));
    }

    public void addPersonToEvent(int personId, int eventId) {
        getEventById(eventId).getPeople().add(getPersonById(personId));
    }
}

我试图通过使用父控制器和对HibernateUtil的静态调用来分离文件：的 HibernateUtil.java

package com.epa.util;

import org.hibernate.SessionFactory;
import org.springframework.transaction.annotation.Transactional;
@Transactional
public class HibernateUtil {

    // So Spring can inject the session factory
    static SessionFactory sessionFactory;
    public void setSessionFactory(SessionFactory value) {
        sessionFactory = value;
    }

    // Shortcut for sessionFactory.getCurrentSession()
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

BaseController.java

package com.epa.controller.base;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.transaction.annotation.Transactional;

import com.epa.controller.EventController;
import com.epa.controller.PersonController;
import com.epa.util.HibernateUtil;

@Transactional
public class BaseController {

    protected SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
    // Shortcut for sessionFactory.getCurrentSession()
    public Session sess() {
        return sessionFactory.getCurrentSession();
    }

    private PersonController personController = null;
    private EventController eventController = null;

    public PersonController getPersonController() {
        if (this.personController == null) {
            this.personController = new PersonController();
        }
        return personController;
    }

    public EventController getEventController() {
        if (this.eventController == null) {
            this.eventController = new EventController();
        }
        return eventController;
    }
}

EventController.java

package com.epa.controller;

import java.util.List;

import org.springframework.transaction.annotation.Transactional;

import com.epa.controller.base.BaseController;
import com.epa.model.Event;

@Transactional
public class EventController extends BaseController {

    public Event getEventById(long id) {
        return (Event) sess().load(Event.class, id);
    }

    public void deleteEventById(long id) {
        sess().delete(getEventById(id));
    }

    public void createEvent(String name) {
        Event theEvent = new Event();
        theEvent.setName(name);
        sess().save(theEvent);
    }

    @SuppressWarnings("unchecked")
    public List getEvents() {
        return sess().createQuery("from Event").list();
    }

}

和spring的 applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/tx 
       http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
       http://www.springframework.org/schema/aop 
       http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">

    <!-- The singleton hibernate session factory -->
    <bean id="sessionFactory" scope="singleton"
        class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
        <property name="configLocation" value="classpath:hibernate.cfg.xml" />
    </bean>

    <!-- Spring's hibernate transaction manager, in charge of making hibernate sessions/txns -->
    <bean id="transactionManager"
        class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory" />
    </bean>

    <!-- So classes/functions with @Transactional get a hibernate txn -->
    <tx:annotation-driven />

    <!-- Inject my business services class to the actions 
    <bean id="services" class="com.epa.services.Services" scope="singleton">
        <property name="sessionFactory" ref="sessionFactory" />
    </bean>-->

    <!-- Inject my business services class to the actions -->
    <bean id="hibernateUtil" class="com.epa.util.HibernateUtil" scope="singleton">
        <property name="sessionFactory" ref="sessionFactory" />
    </bean> 

    <bean id="baseController" class="com.epa.controller.base.BaseController" scope="singleton" />

</beans>

Answer 1

你的代码看起来好像你没有完全理解Spring依赖注入的概念，因为你的BaseController做了Spring管理单例和提供依赖的工作。

<强>问题

您正在EventController内自行创建PersonController和BaseController个实例，而不是依赖Spring。 Spring无法拦截类实例的手动创建，并通过使用Spring注释@Transactional注释类来为它们提供所需的事务行为。

<强>解决方案

所以，让我们找一个清理这段代码的路径。首先删除类HibernateUtil，因为它是静态调用，java bean概念和未使用的事务行为的混合，同时它带来了一个没有任何好处的新抽象层。请务必将其从applicationContext.xml中删除。

现在也从您的BaseController中移除applicationContext.xml，然后对其进行重大改写，因为它可以作为PersonController和EventController的单身工厂工作，可以正确管理Spring本身就是在这样的环境中。

public abstract class BaseController {

    private SessionFactory sessionFactory;

    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
    }

    protected Session getCurrentSession() {
        return sessionFactory.getCurrentSession();
    }

}

这种方式BaseController成为其他扩展类的抽象基类，可以使用提供的Hibernate Session对象。现在让我们为EventController创建一个漂亮的界面。

public interface EventController {

    Event getEventById(long id);

    void deleteEventById(long id);

    Event createEvent(String name);

    List getEvents();

}

接下来我们需要为Hibernate实现上面的接口，所以让我们使用之前创建的EventControllerHibernate实现来调用新类BaseController。

public class EventControllerHibernate extends BaseController implements EventController {

    @Transactional(propagation = Propagation.SUPPORTS, readOnly = true)
    public Event getEventById(long id) {
        return (Event) getCurrentSession().get(Event.class, id);
    }

    @Transactional(propagation = Propagation.REQUIRED)
    public void deleteEventById(long id) {
        getCurrentSession().delete(getEventById(id));
    }

    @Transactional(propagation = Propagation.REQUIRED)
    public Event createEvent(String name) {
         return (Event) getCurrentSession().save(new Event(name));
    }

    @Transactional(propagation = Propagation.SUPPORTS, readOnly = true)
    @SuppressWarnings("unchecked")
    public List getEvents() {
        return getCurrentSession().createQuery("from Event").list();
    }

}

请记住在春季applicationContext.xml正确注册此课程，以便提供所需的SessionFactory：

<bean id="eventController" class="com.epa.controller.EventControllerHibernate">
    <property name="sessionFactory" ref="sessionFactory" />
</bean>

如果从Spring检索类型为EventController的Spring bean，您将获得一个事务感知代理对象，完全实现委托给EventController内部实现的业务逻辑的EventControllerHibernate接口。

记住：应用程序中永远不会出现new EventControllerHibernate()，因为这不会起作用，因为Spring无法拦截手动创建类实例！以编程方式获取事务感知实例将如下所示：

ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
EventController eventController = context.getBean("eventController", EventController.class);

Answer 2

控制器代码不是很优雅。你应该遵循codescape在这里所说的一切。但是，对问题的简单修复如下：您可以返回已注入BaseController（）的bean实例，而不是返回新的PersonController（）或新的EventController（）。这将返回一个代理对象，可以通过spring拦截@Transactional。但是，正如我所说，定义的控制器不是好的代码。

Hibernate和Spring - 加载操作执行trich，更新/删除操作不执行

2 个答案: