spring事务小案例
【该方法有缺陷，解决问题的版本在最后】
如果需要哪个方法用到事务，需要把这个方法所在类交给spring管理
可以把这个方法放进已经被spring管理的dao内
（@Transactional(propagation= Propagation.REQUIRED, rollbackFor = Exception.class)）
（@Transactional(isolation=Isolation.REPEATABLE_READ,propagation=Propagation.REQUIRED,readOnly=false)）
<bean name="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager" >
<property name="sessionFactory" ref="sessionFactory" ></property>
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />
WebDao.java
package dao; import org.hibernate.SessionFactory; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.orm.hibernate4.HibernateTemplate; import org.springframework.orm.hibernate4.support.HibernateDaoSupport; import org.springframework.transaction.annotation.Isolation; import org.springframework.transaction.annotation.Propagation; import org.springframework.transaction.annotation.Transactional; import bean.bean2; @Transactional(isolation=Isolation.REPEATABLE_READ,propagation=Propagation.REQUIRED,readOnly=false) public class WebDao extends HibernateDaoSupport { public WebDao() { System.out.println("dao"); } public void save(bean2 bean2) { System.out.println(bean2); HibernateTemplate hibernateTemplate= this.getHibernateTemplate(); System.out.println("hibernateTemplate:"+hibernateTemplate); getHibernateTemplate().setCheckWriteOperations(false); this.getHibernateTemplate().save(bean2); System.out.println("保存成功！"); } public void test(bean2 bean2,bean2 bean3) { System.out.println(bean2); getHibernateTemplate().setCheckWriteOperations(false); this.getHibernateTemplate().save(bean2); System.out.println("bean2保存成功！"); System.out.println(bean3); getHibernateTemplate().setCheckWriteOperations(false); this.getHibernateTemplate().save(bean3); //--------空指针异常 int arr[] = { 1 }; System.out.println(arr[10]); System.out.println("bean3保存成功！"); } }
aaplicationContext.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd"> <bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="jdbcUrl" value="jdbc:mysql:///test"></property> <property name="driverClass" value="com.mysql.jdbc.Driver"></property> <property name="user" value="root"></property> <property name="password" value="root"></property> </bean> <!--事务模块(不使用注解的事务) begin--> <!-- 核心事务管理器 --> <bean name="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager" > <property name="sessionFactory" ref="sessionFactory" ></property> </bean> <tx:annotation-driven transaction-manager="transactionManager"/> <!-- 配置通知 --> <tx:advice id="txAdvice" transaction-manager="transactionManager" > <tx:attributes> <tx:method name="save*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" /> <tx:method name="persist*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" /> <tx:method name="update*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" /> <tx:method name="modify*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" /> <tx:method name="delete*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" /> <tx:method name="remove*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" /> <tx:method name="get*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="true" /> <tx:method name="find*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="true" /> <tx:method name="*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" /> </tx:attributes> </tx:advice> <!-- 配置将通知织入目标对象 配置切点 配置切面 --> <!--事务模块(不使用注解的事务) end --> <!-- ========================================================================================= --> <!-- 开启注解事务 <tx:annotation-driven transaction-manager="transactionManager" /> --> <!-- 将SessionFactory配置到spring容器中 --> <!-- 加载配置方案1:仍然使用外部的hibernate.cfg.xml配置信息 --> <!-- <bean name="sessionFactory" class="org.springframework.orm.hibernate5.LocalSessionFactoryBean" > <property name="configLocation" value="classpath:hibernate.cfg.xml" ></property> </bean> --> <bean name="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean"> <property name="dataSource" ref="dataSource"></property> <property name="hibernateProperties"> <props> <!-- 必选配置 --> <prop key="hibernate.connection.driver_class" >com.mysql.jdbc.Driver</prop> <prop key="hibernate.connection.url" >jdbc:mysql:///test</prop> <prop key="hibernate.connection.username" >root</prop> <prop key="hibernate.connection.password" >root</prop> <!-- 可选配置 --> <prop key="hibernate.dialect" >org.hibernate.dialect.MySQLDialect</prop> <prop key="hibernate.show_sql" >true</prop> <prop key="hibernate.format_sql" >true</prop> <prop key="hibernate.hbm2ddl.auto" >update</prop> </props> </property> <!-- 引入orm元数据,指定orm元数据所在的包路径,spring会自动读取包中的所有配置 --> <property name="mappingDirectoryLocations" value="classpath:" ></property> </bean> <bean name="bean1" class="bean.bean1"></bean> <bean name="bean2" class="bean.bean2"> <property name="bean1" ref="bean1"></property> <property name="name" value="test"></property> </bean> <bean name="beanDao" class="dao.WebDao"> <property name="sessionFactory" ref ="sessionFactory"> </property></bean> </beans>
在xml配置文件中开启注解
测试类TransTest.java中的主函数
public static void main(String[] args) { ApplicationContext ac = new ClassPathXmlApplicationContext( "applicationContext.xml"); WebDao dao = (WebDao) ac.getBean("beanDao"); System.out.println("........."); bean2 bean2 = (bean2) ac.getBean("bean2"); bean2.setName("事务测试1"); bean2 bean3 = (bean2) ac.getBean("bean2"); bean3.setName("事务测试2"); System.out.println("........."); dao.test(bean2, bean3); }
运行后，数据库内不会插入数据，而且自增长的id会跳过这个数字
【无异常，正常插入两条数据的事务】
WebDao.java中的方法（修改后）
保存完第一个bean后要使用clear()方法清除缓存
public void test(bean2 bean2,bean2 bean3) { System.out.println(bean2); getHibernateTemplate().setCheckWriteOperations(false); this.getHibernateTemplate().save(bean2); System.out.println("bean2保存成功！"); this.getHibernateTemplate().clear(); System.out.println(bean3); getHibernateTemplate().setCheckWriteOperations(false); this.getHibernateTemplate().save(bean3); //--------空指针异常 // int arr[] = { 1 }; // System.out.println(arr[10]); System.out.println("bean3保存成功！"); }
TransTest.java中的主函数（修改后）
public static void main(String[] args) { ApplicationContext ac = new ClassPathXmlApplicationContext( "applicationContext.xml"); WebDao dao = (WebDao) ac.getBean("beanDao"); System.out.println("........."); //bean2 bean2 = new bean2("123",1); bean2 bean2 = (bean2) ac.getBean("bean2"); bean2.setName("事务测试1"); bean2 bean3 = new bean2("123",1); bean3.setName("事务测试2"); System.out.println("........."); dao.test(bean2, bean3); }
一个注意的点，把bean交给spring管理后，默认会有一个无参构造函数，如果自己后来又添加了有参构造，还需要自己补上一个无参构造
bean2.java(修改后)
package bean; public class bean2 { String name="0"; int id=1; public bean2() { } public bean2(String name, int id) { super(); this.name = name; this.id = id; } public void setBean1(bean1 bean1){ System.out.println("bean2注入bean1："+bean1); this.name=bean1.getName(); } public void setName(String name) { this.name = name; System.out.println("bean2修改name："+name); } public String getName() { return name; } public void setId(int id) { System.out.println("bean2setid"); this.id = id; } public int getId() { return id; } @Override public String toString() { return "bean2 [name=" + name + "]"; } }
