上一节我们介绍了spring 事务中的相关接口,这一节我们看看怎么利用接口通过编程式来使用事务控制。使用TransactionTemplate来实现编程式事务控制。使用TransactionTemplate 不需要显式地开始事务,甚至不需要显式地提交事务。这些步骤都由模板完成。但出现异常时,应通过TransactionStatus 的setRollbackOnly 显式回滚事务。 TransactionTemplate 的execute 方法接收一个TransactionCallback 实例。如果事务的执行体没有返回值,则可以使用TransactionCallbackWithoutResultl类的实例。
这一节我们使用mysql数据库进行演示,通过一个账户转账示例来保证两个账户数据的一致性。
创建表
CREATE TABLE `useraccount` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(50) DEFAULT NULL,
`money` double DEFAULT '0',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8
引入依赖组件
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.2.5.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.mchange/c3p0 -->
<dependency>
<groupId>com.mchange</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.5</version>
</dependency>
<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.36</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>4.2.2.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.annotation/javax.annotation-api -->
<dependency>
<groupId>javax.annotation</groupId>
<artifactId>javax.annotation-api</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
创建数据库持久层
package com.trans.trans01;
public interface IUserAccountDao {
//转出账户
public void TransferOut(String user,double money);
//转入账户
public void TransferIn(String user,double money);
}
package com.trans.trans01;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
public class UserAccountDao extends JdbcDaoSupport implements IUserAccountDao {
public void TransferOut(String user, double money) {
// TODO Auto-generated method stub
String sql="UPDATE `useraccount` SET money=money-? WHERE username=?";
this.getJdbcTemplate().update(sql, money,user);
}
public void TransferIn(String user, double money) {
// TODO Auto-generated method stub
String sql="UPDATE `useraccount` SET money=money+? WHERE username=?";
this.getJdbcTemplate().update(sql, money,user);
}
}
创建业务层
package com.trans.trans01;
public interface IUserAccoutService {
//fromAccount来源账户 toAccount目标账户,money金额
public void UserTransferMoney(String fromAccount,String toAccount,double money);
}
package com.trans.trans01;
import javax.annotation.Resource;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.TransactionCallback;
import org.springframework.transaction.support.TransactionCallbackWithoutResult;
import org.springframework.transaction.support.TransactionTemplate;
public class UserAccoutService implements IUserAccoutService {
@Resource(name="userAccountDao")
private IUserAccountDao userAccountDao;
private TransactionTemplate transactionTemplate;
public void setTransactionTemplate(TransactionTemplate transactionTemplate) {
this.transactionTemplate = transactionTemplate;
}
public void UserTransferMoney(final String fromAccount,final String toAccount,
final double money) {
transactionTemplate.execute(new TransactionCallbackWithoutResult() {
@Override
protected void doInTransactionWithoutResult(TransactionStatus arg0) {
// TODO Auto-generated method stub
// TODO Auto-generated method stub
userAccountDao.TransferOut(fromAccount, money);//转出账户
int m=10/0;
userAccountDao.TransferIn(toAccount, money);//转入账户
}
});
}
}
jdbc.properties
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/erp?useUnicode=true&characterEncoding=utf8
jdbc.username=root
jdbc.password=123456
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:context="http://www.springframework.org/schema/context"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:p="http://www.springframework.org/schema/p"
xmlns:cache="http://www.springframework.org/schema/cache" xmlns:repo="http://www.springframework.org/schema/data/repository"
xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jpa="http://www.springframework.org/schema/data/jpa"
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/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
http://www.springframework.org/schema/data/repository http://www.springframework.org/schema/data/repository/spring-repository-1.7.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd "
default-lazy-init="true">
<description>Spring配置</description>
<context:annotation-config />
<!-- 引入数据源配置文件 -->
<context:property-placeholder location="src/main/java/com/trans/trans01/jdbc.properties"/>
<!-- 连接池 -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="${jdbc.driverClass}"></property>
<property name="jdbcUrl" value="${jdbc.url}"></property>
<property name="user" value="${jdbc.username}"></property>
<property name="password" value="${jdbc.password}"></property>
</bean>
<!-- 持久层 -->
<bean id="userAccountDao" class="com.trans.trans01.UserAccountDao">
<property name="dataSource" ref="dataSource"></property>
</bean>
<bean id="userAccoutService" class="com.trans.trans01.UserAccoutService">
<property name="transactionTemplate" ref="transactionTemplate"></property>
</bean>
<!-- 配置事务管理其 -->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<!-- 注入数据连接池 -->
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 配置事务管理模板 -->
<bean id="transactionTemplate" class="org.springframework.transaction.support.TransactionTemplate">
<!-- 注入事务管理其 -->
<property name="transactionManager" ref="transactionManager"></property>
</bean>
</beans>
运行public class App
{
public static void main( String[] args )
{
//ApplicationContext context = new FileSystemXmlApplicationContext("D:\\demo\\javademo\\trans01\\src\\main\\java\\com\\trans\\trans01\\applicationContext.xml");
//ApplicationContext context = new FileSystemXmlApplicationContext("D:\\demo\\javademo\\trans01\\src\\main\\java\\com\\trans\\trans01\\applicationContext.xml");
//ApplicationContext context = new ClassPathXmlApplicationContext("classpath:src/main/java/applicationContext.xml");
ApplicationContext context = new FileSystemXmlApplicationContext("src/main/java/com/trans/trans01/applicationContext.xml");
IUserAccoutService service=(IUserAccoutService)context.getBean("userAccoutService");
service.UserTransferMoney("001", "002", 100);
}
}
DEMO下载 http://download.youkuaiyun.com/detail/zx13525079024/9590518