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我在我的演示应用程序中使用 Hibernate+Spring+Jsf 我希望 Spring 将处理事务管理所以我在 application-context.xml 文件中创建了这些条目..

    <beans xmlns="http://www.springframework.org/schema/beans"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xmlns:tx="http://www.springframework.org/schema/tx"
            xmlns:context="http://www.springframework.org/schema/context"
            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/context 
                    http://www.springframework.org/schema/context/spring-context-3.0.xsd">

        <!-- Beans Declaration -->
        <bean id="User" class="com.otv.model.User"/>

        <!-- User Service Declaration -->
        <bean id="UserService" class="com.otv.user.service.UserService">
            <property name="userDAO" ref="UserDAO" />
        </bean>

        <!-- User DAO Declaration -->
        <bean id="UserDAO" class="com.otv.user.dao.UserDAO">
            <property name="sessionFactory" ref="SessionFactory" />
        </bean>

        <!-- Data Source Declaration -->
        <bean id="DataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
            <property name="driverClass" value="org.postgresql.Driver" />   
            <property name="jdbcUrl" value="jdbc:postgresql://localhost:5432/postgres" />   
            <property name="user" value="postgres" />   
            <property name="password" value="hariom" /> 
            <property name="maxPoolSize" value="10" />
            <property name="maxStatements" value="0" />
            <property name="minPoolSize" value="5" /> 
        </bean>

        <!-- Session Factory Declaration -->
        <bean id="SessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
            <property name="dataSource" ref="DataSource" />
            <property name="annotatedClasses">
                <list>
                    <value>com.otv.model.User</value>
                </list>
            </property>
            <property name="hibernateProperties">
                <props>
                    <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
                    <prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.connection.autocommit">false</prop>
                </props>
            </property>
        </bean>

        <!-- Enable the configuration of transactional behavior based on annotations -->
        <tx:annotation-driven transaction-manager="txManager"/>

        <!-- Transaction Manager is defined -->
        <bean id="txManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
           <property name="sessionFactory" ref="SessionFactory"/>
        </bean>

    </beans>

和 UserService.java 类

package com.otv.user.service;

import java.util.List;

import org.springframework.transaction.annotation.Transactional;

import com.otv.model.User;
import com.otv.user.dao.IUserDAO;

/**
 * 
 * User Service
 * 
 * @author onlinetechvision.com
 * @since 25 Mar 2012
 * @version 1.0.0
 *
 */
@Transactional(readOnly = true)
public class UserService implements IUserService {

    // UserDAO is injected...
    IUserDAO userDAO;

    /**
     * Add User
     * 
     * @param  User user
     */
    @Transactional(readOnly = false)
    public void addUser(User user) {
        getUserDAO().addUser(user);
    }

    /**
     * Delete User
     * 
     * @param  User user
     */
    @Transactional(readOnly = false)
    public void deleteUser(User user) {
        getUserDAO().deleteUser(user);
    }

    /**
     * Update User
     * 
     * @param  User user
     */
    @Transactional(readOnly = false)
    public void updateUser(User user) {
        getUserDAO().updateUser(user);
    }

    /**
     * Get User
     * 
     * @param  int User Id
     */
    public User getUserById(int id) {
        return getUserDAO().getUserById(id);
    }

    /**
     * Get User List
     * 
     */
    public List<User> getUsers() {  
        return getUserDAO().getUsers();
    }

    /**
     * Get User DAO
     * 
     * @return IUserDAO - User DAO
     */
    public IUserDAO getUserDAO() {
        return userDAO;
    }

    /**
     * Set User DAO
     * 
     * @param IUserDAO - User DAO
     */
    public void setUserDAO(IUserDAO userDAO) {
        this.userDAO = userDAO;
    }

}

现在我在做我的豆子

@ManagedProperty(value="#{UserService}")
    IUserService userService;

     */
    public IUserService getUserService() {
        return userService;
    }

    /**
     * Set User Service
     * 
     * @param IUserService - User Service
     */
    public void setUserService(IUserService userService) {
        this.userService = userService;
    }

    public String addUser() {
        try {
            User user = new User();
            user.setId(getId());
            user.setName(getName());
            user.setSurname(getSurname());
            userService = getUserService();
            userService.addUser(user);
            userService.deleteUser(null);
            return SUCCESS;
        } catch (DataAccessException e) {
            e.printStackTrace();
        }   

        return ERROR;
    }

在这段代码中userService.deleteUser(null); ,我强行通过异常但仍将数据保存在数据库中?如果出现异常,为什么不回滚数据,为什么不处理这种情况?

UserDAO 类

package com.otv.user.dao;

import java.util.List;

import com.otv.model.User;

import org.hibernate.SessionFactory;


public class UserDAO implements IUserDAO {

    private SessionFactory sessionFactory;

    /**
     * Get Hibernate Session Factory
     * 
     * @return SessionFactory - Hibernate Session Factory
     */
    public SessionFactory getSessionFactory() {
        return sessionFactory;
    }

    /**
     * Set Hibernate Session Factory
     * 
     * @param SessionFactory - Hibernate Session Factory
     */
    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
    }

    /**
     * Add User
     * 
     * @param  User user
     */
    public void addUser(User user) {
        getSessionFactory().getCurrentSession().save(user);
    }

    /**
     * Delete User
     * 
     * @param  User user
     */
    public void deleteUser(User user) {
        getSessionFactory().getCurrentSession().delete(user);
    }

    /**
     * Update User
     * 
     * @param  User user
     */
    public void updateUser(User user) {
        getSessionFactory().getCurrentSession().update(user);
    }

    /**
     * Get User
     * 
     * @param  int User Id
     * @return User 
     */
    public User getUserById(int id) {
        List list = getSessionFactory().getCurrentSession()
                                            .createQuery("from User where id=?")
                                            .setParameter(0, id).list();
        return (User)list.get(0);
    }

    /**
     * Get User List
     * 
     * @return List - User list
     */
    public List<User> getUsers() {
        List list = getSessionFactory().getCurrentSession().createQuery("from User").list();
        return list;
    }

}
4

2 回答 2

2

似乎事务边界是 UserService 类上的每个方法。当您说userService.addUser(user)这是一项交易的开始和完成时。因此,当您说userService.deleteUser(null)这是另一个事务时——尽管它失败了,但前一个事务并没有回滚,因为它已经被提交了。

如果您想在一个事务中完成所有操作,请使用 @Transactional 注释您的 addUser() (或包含在程序化事务中)

于 2013-02-11T21:53:04.517 回答
1

方法上的@Transactional注释定义了事务的边界(除非其他人已经在运行“外部事务”)。同样,类的@Transactional注释使对该类实例的(公共)方法的所有单个调用都具有事务性,但不会使对同一实例的连续方法调用被包装在单个事务中。相反,每个方法调用都在其自己的事务中运行,如果方法正常返回,则提交事务。(默认情况下,如果抛出已检查的异常,它甚至会被提交,尽管您可以使用rollbackForandnoRollbackFor参数更改它。)

因此,在您的情况下,您有两笔交易;一个用于此呼叫:

userService.addUser(user);

它成功创建了一个用户并在调用addUser完成后提交,第二个:

userService.deleteUser(null);

当 NullPointerException 从方法调用中引发时,它会回滚。(我猜你在这里得到了一个 NPE,因为这是 RuntimeExcepotion 的一个子类,它会导致回滚。)

如果您想在单个事务中包含两个语句,则需要将事务置于更高级别。这里的 '@Transactional` 注释不会有什么坏处,但它们不是你想要的。

于 2013-02-11T21:53:49.343 回答