Java事务管理之Spring+Hibernate

时间:2021-01-24 12:08:29

环境与版本

除了上一篇中的hibernate的相关lib 外

Java事务管理之Hibernate

还需要加入Spring的lib 包和如下的一些依赖包

org.aopalliance
org.aspectj
org.apache.commons

Spring 的版本是Spring 4.1.5。

依赖包也可以到Spring 官方网站下载到 ,名字类似 spring-framework-3.0.2.RELEASE-dependencies

理论知识

Spring和Hibernate整合后,通过Hibernate API进行数据库操作时发现每次都要opensession,close,beginTransaction,commit,这些都是重复的工作,我们可以把事务管理部分交给spring框架完成。

使用spring管理事务后在dao中不再需要调用beginTransaction和commit,也不需要调用session.close(),使用API  sessionFactory.getCurrentSession()来替代sessionFactory.openSession()

* 如果使用的是本地事务(jdbc事务)
<property name="hibernate.current_session_context_class">thread</property>
* 如果使用的是全局事务(jta事务)
<property name="hibernate.current_session_context_class">jta</property>

Spring中Propagation类的事务属性详解:
PROPAGATION_REQUIRED:支持当前事务,如果当前没有事务,就新建一个事务。这是最常见的选择。 
PROPAGATION_SUPPORTS:支持当前事务,如果当前没有事务,就以非事务方式执行。 
PROPAGATION_MANDATORY:支持当前事务,如果当前没有事务,就抛出异常。 
PROPAGATION_REQUIRES_NEW:新建事务,如果当前存在事务,把当前事务挂起。
PROPAGATION_NOT_SUPPORTED:以非事务方式执行操作,如果当前存在事务,就把当前事务挂起。 
PROPAGATION_NEVER:以非事务方式执行,如果当前存在事务,则抛出异常。 
PROPAGATION_NESTED:支持当前事务,如果当前事务存在,则执行一个嵌套事务,如果当前没有事务,就新建一个事务。

Spring 可以使用xml方式进行配置或是使用注解声明的方式进行事务的管理。

xml 方式配置事务代码实例

代码结构如下:

Java事务管理之Spring+Hibernate

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:p="http://www.springframework.org/schema/p"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:util="http://www.springframework.org/schema/util" xmlns:mvc="http://www.springframework.org/schema/mvc"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:aop="http://www.springframework.org/schema/aop"
	xsi:schemaLocation="
        http://www.springframework.org/schema/util
        http://www.springframework.org/schema/util/spring-util-3.1.xsd
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-3.1.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-3.1.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">

	<context:component-scan base-package="com.oscar999.trans.sprhib" />
	<context:property-placeholder location="classpath:/com/oscar999/trans/sprhib/config.properties" />
	<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
		destroy-method="close">
		<!-- Connection Info -->
		<property name="driverClassName" value="${jdbc.driver}" />
		<property name="url" value="${jdbc.url}" />
		<property name="username" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}"></property>
	</bean>

	<bean id="sessionFactory"
		class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
		<property name="dataSource" ref="dataSource"></property>
		<property name="hibernateProperties">
			<props>
				<prop key="hibernate.dialect">org.hibernate.dialect.OracleDialect</prop>
				<prop key="hibernate.hbm2ddl.auto">update</prop>
				<prop key="hibernate.show_sql">true</prop>
				<prop key="hibernate.format_sql">true</prop>
				<prop key="hibernate.jdbc.batch_size">20</prop>
				<prop key="hibernate.enable_lazy_load_no_trans">true</prop>
				<prop key="hibernate.current_session_context_class">org.springframework.orm.hibernate4.SpringSessionContext</prop>
				<prop key="jdbc.use_streams_for_binary">true</prop>
			</props>
		</property>
		<property name="packagesToScan">
			<list>
				<value>com.oscar999.trans.sprhib.model</value>
			</list>
		</property>
	</bean>

	<!-- Transaction -->
	<bean id="transactionManager"
		class="org.springframework.orm.hibernate4.HibernateTransactionManager">
		<property name="sessionFactory" ref="sessionFactory" />
	</bean>
	<tx:advice id="txAdvice" transaction-manager="transactionManager">
		<tx:attributes>
			<tx:method name="save*" propagation="REQUIRED" />
			<tx:method name="*" read-only="true" />
		</tx:attributes>
	</tx:advice>
	<aop:config proxy-target-class="true">
		<aop:pointcut expression="execution(* com.oscar999.trans.sprhib.dao.ProductDAOImpl.*(..))" id="pointcut" />
		<aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut" />
	</aop:config>

</beans>

config.properties

jdbc.driver=oracle.jdbc.driver.OracleDriver
jdbc.url=jdbc:oracle:thin:@12.6.18.43:1521:orcl
jdbc.username=
jdbc.password=oracle

Product.java

/**
 * @Title: Product.java
 * @Package com.oscar999.trans.hibernate
 * @Description:
 * @author XM
 * @date Feb 15, 2017 1:44:47 PM
 * @version V1.0
 */
package com.oscar999.trans.sprhib.model;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;

/**
 * @author XM
 *
 */
@Entity
@Table(name = "TEST_PRODUCT")
public class Product implements Serializable {

	public Product() {
	}

	@Id
	@Column(name = "ID")
	private Integer id;

	@Column(name = "NAME")
	private String name;

	@Column(name = "PRICE")
	private String price;

	private static final long serialVersionUID = 1L;

	public Integer getId() {
		return id;
	}

	public void setId(Integer id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getPrice() {
		return price;
	}

	public void setPrice(String price) {
		this.price = price;
	}

}

ProductDAOImpl.java

/**
 * @Title: ProductDAOImpl.java
 * @Package com.oscar999.trans.sprhib
 * @Description:
 * @author XM
 * @date Feb 15, 2017 4:15:09 PM
 * @version V1.0
 */
package com.oscar999.trans.sprhib.dao;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

import com.oscar999.trans.sprhib.model.Product;

/**
 * @author XM
 *
 */
@Repository
public class ProductDAOImpl {

	@Autowired
	private SessionFactory sessionFactory; 

	public Product findProductById(int id) {
		Session session = sessionFactory.getCurrentSession();
		Product product = (Product) session.get(Product.class, id);
		return product;
	}

	public Product saveProduct(Product product) {
		Session session = sessionFactory.getCurrentSession();
		session.save(product);
		return product;
	}
}

ProductServiceImpl.java

package com.oscar999.trans.sprhib;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.oscar999.trans.sprhib.dao.ProductDAOImpl;
import com.oscar999.trans.sprhib.model.Product;

@Service
public class ProductServiceImpl {

	@Autowired
	private ProductDAOImpl productdao;

	public void findProduct(int id) {
		Product product = productdao.findProductById(id);
		if (product != null) {
			System.out.println(product.getName());
		}
	}

	public void saveProduct() {
		Product product = new Product();
		product.setId(2);
		product.setName("product2");
		product.setPrice("price2");
		productdao.saveProduct(product);

	}
}

TestMain.java

/**
 * @Title: TestMain.java
 * @Package com.oscar999.trans.sprhib
 * @Description:
 * @author XM
 * @date Feb 15, 2017 3:54:54 PM
 * @version V1.0
 */
package com.oscar999.trans.sprhib;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * @author XM
 *
 */
public class TestMain {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("com/oscar999/trans/sprhib/applicationContext.xml");
		ProductServiceImpl productService = applicationContext.getBean(ProductServiceImpl.class);
		//productService.findProduct(1);
		productService.saveProduct();
	}

}

说明如下:

get 可以不需要transaction
插入或是更新如果没有的话, 就不会更新成功

声明方式配置事务

需要在xml配制中设置<tx:annotation-driven transaction-manager="transactionManager"> 
事物注解方式: @Transactional
当标于类前时,标示类中所有方法都进行事物处理,以下代码在service层进行事务处理(给Service层配置事务是比较好的方式,因为一个Service层方法操作可以关联到多个DAO的操作。在Service层执行这些Dao操作,多DAO操作有失败全部回滚,成功则全部提交。)

@Service

@Transactional

public class UserServiceImpl implements UserService {

@Autowired

private UserDao userDao;

public User getUserById(int id) {

return userDao.findUserById(id);

}

}

当类中某些方法不需要事物时:
@Service

@Transactional

public class UserServiceImpl implements UserService {

@Autowired

private UserDao userDao;

@Transactional(propagation = Propagation.NOT_SUPPORTED)

public User getUserById(int id) {

return userDao.findUserById(id);

}

}