spring 事物（二）—— 编程式事物实现与扩展
简介
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。Callback 也是Spring 的经典设计，用于简化用户操作。
TransactionCallback 包含如下方法。
• Object dolnTransaction(TransactionStatus status) 。
该方法的方法体就是事务的执行体。
如果事务的执行体没有返回值，则可以使用TransactionCallbackWithoutResultl类的实例。这是个抽象类，不能直接实例化，只能用于创建匿名内部类。它也是TransactionCallback 接口的子接口，该抽象类包含一个抽象方法:
• void dolnTransactionWithoutResult(TransactionStatus status)该方法与dolnTransaction 的效果非常相似，区别在于该方法没有返回值，即事务执行体无须返回值。
transactionTemplate.execute(new TransactionCallback() {
public Object doInTransaction(TransactionStatus status) {
try{
}
catch (Exception e) {
status.setRollbackOnly();
}
}
}); 简单实现
SQL:
create table `account` (
`username` varchar (99),
`salary` int (11)
);
insert into `account` (`username`, `salary`) values('小王','3000');
insert into `account` (`username`, `salary`) values('小马','3000');
注意： 通过添加/删除accountMoney() 方法中int i = 10 / 0这个语句便可验证事务管理是否配置正确。
OrdersDao.java(Dao层)
package com.gm.dao;
import org.springframework.jdbc.core.JdbcTemplate;
public class OrdersDao {
// 注入jdbcTemplate模板对象
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
// 对数据操作的方法不包含业务操作
/**
* 小王少钱的方法
*/
public void reduceMoney() {
String sql = "update account set salary=salary-? where username=?";
jdbcTemplate.update(sql, 1000, "小王");
}
/**
* 小马多钱的方法
*/
public void addMoney() {
String sql = "update account set salary=salary+? where username=?";
jdbcTemplate.update(sql, 1000, "小马");
}
}
OrdersService.java（业务逻辑层）
package com.gm.service;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.TransactionCallback;
import org.springframework.transaction.support.TransactionTemplate;
import com.gm.dao.OrdersDao;
public class OrdersService {
private final static Logger LOG = LoggerFactory.getLogger(OrdersService.class);
// 注入Dao层对象
private OrdersDao ordersDao;
public void setOrdersDao(OrdersDao ordersDao) {
this.ordersDao = ordersDao;
}
// 注入TransactionTemplate对象
private TransactionTemplate transactionTemplate;
public void setTransactionTemplate(TransactionTemplate transactionTemplate) {
this.transactionTemplate = transactionTemplate;
}
// 调用dao的方法
// 业务逻辑，写转账业务
public void accountMoney() {
transactionTemplate.execute(new TransactionCallback<Object>() {
@Override
public Object doInTransaction(TransactionStatus status) {
Object result = null;
try {
// 小马多1000
ordersDao.addMoney();
// 加入出现异常如下面int
// i=10/0（银行中可能为突然停电等。。。）；结果：小马账户多了1000而小王账户没有少钱
// 解决办法是出现异常后进行事务回滚
int i = 10 / 0;// 事务管理配置后异常已经解决
// 小王 少1000
ordersDao.reduceMoney();
} catch (Exception e) {
status.setRollbackOnly();
result = false;
LOG.error("Transfer Error!，"+e.getMessage());
}
return result;
}
});
}
}
TestService.java（测试方法）
package com.gm.service;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class TestService {
@Test
public void testAdd() {
ApplicationContext context = new ClassPathXmlApplicationContext(
"beans.xml");
OrdersService userService = (OrdersService) context
.getBean("ordersService");
userService.accountMoney();
}
}
配置文件：
<?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:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">
<!-- 配置c3po连接池 -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<!-- 注入属性值 -->
<property name="driverClass" value="com.mysql.jdbc.Driver"></property>
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/mydb"></property>
<property name="user" value="root"></property>
<property name="password" value="153963"></property>
</bean>
<!-- 编程式事务管理 -->
<!-- 配置事务管理器 -->
<bean id="dataSourceTransactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<!-- 注入dataSource -->
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 配置事务管理器模板 -->
<bean id="transactionTemplate"
class="org.springframework.transaction.support.TransactionTemplate">
<!-- 注入真正进行事务管理的事务管理器,name必须为 transactionManager否则无法注入 -->
<property name="transactionManager" ref="dataSourceTransactionManager"></property>
</bean>
<!-- 对象生成及属性注入 -->
<bean id="ordersService" class="com.gm.service.OrdersService">
<property name="ordersDao" ref="ordersDao"></property>
<!-- 注入事务管理的模板 -->
<property name="transactionTemplate" ref="transactionTemplate"></property>
</bean>
<bean id="ordersDao" class="com.gm.dao.OrdersDao">
<property name="jdbcTemplate" ref="jdbcTemplate"></property>
</bean>
<!-- JDBC模板对象 -->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"></property>
</bean>
</beans> log4j.properties
#Level:ERROR,WARN,INFO,DEBUG
log4j.rootLogger=ERROR, console
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.target=System.out
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=[%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n
执行，输出
[ERROR] 2018-09-06 14:03:06,937 method:com.gm.service.OrdersService$1.doInTransaction(OrdersService.java:54)
Transfer Error!，/ by zero
扩展
首先定义了两个接口：
ServiceTemplate ----> 对TransactionTemplate进行了封装
public interface ServiceTemplate {
/**
* <pre> 无事务模板执行业务处理
* 1. 异常捕获，及分类处理
* 2. 业务日志记录
* </pre>
*
* @param <T>
* @param clazz 返回对象
* @param action 业务操作回调的接口
* @return 服务返回对象
*/
<T> T executeWithoutTransaction(Class<? extends Result> clazz, ServiceCallback action);
/**
* <pre> 支持本地事务模板执行业务处理
* 1. 本地事务封装
* 2. 异常捕获，及分类处理
* 3. 业务日志记录
* </pre>
*
* @param <T>
* @param clazz 返回对象
* @param action 业务操作回调的接口
* @return 服务返回对象
*/
<T> T execute(Class<? extends Result> clazz, ServiceCallback action);
}ServiceCallback ----> 对TransactionCallBack进行了封装
public interface ServiceCallback {
/**
* <pre> 校验
* 对于校验不通过，异常驱动返回
* </pre>
*/
void doLock();
/**
* <pre> 校验
* 对于校验不通过，异常驱动返回
* </pre>
*/
void check();
/**
* <pre> 执行业务逻辑
* </pre>
* @return
*/
Result executeService();
}ServiceTemplate的具体实现ServiceTemplateImpl.java
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.TransactionCallback;
import org.springframework.transaction.support.TransactionTemplate;
public class ServiceTemplateImpl implements ServiceTemplate {
private final static Logger LOG = LoggerFactory.getLogger(ServiceTemplateImpl.class);
// 注入TransactionTemplate对象
private TransactionTemplate transactionTemplate;
public void setTransactionTemplate(TransactionTemplate transactionTemplate) {
this.transactionTemplate = transactionTemplate;
}
@Override
public <T> T executeWithoutTransaction(Class<? extends Result> clazz,
ServiceCallback action) {
Result result = null;
try {
// 执行校验
action.check();
// 锁操作
action.doLock();
// 执行处理逻辑
result = action.executeService();
// 可以对结果进行初步校验TODO
} catch (Exception e) {//此处可换成具体异常或子定义异常
LOG.error("Transfer Error！，"+e.getMessage());
// 打日志TODO
return (T) result;
} catch (Throwable e2) {
LOG.error(e2.getMessage());
// 打日志TODO
return (T) result;
}
return (T) result;
}
@Override
@SuppressWarnings("unchecked")
public <T> T execute(final Class<? extends Result> clazz,
final ServiceCallback action) {
T acResult = (T) transactionTemplate.execute(new TransactionCallback() {
/**
* @see org.springframework.transaction.support.TransactionCallback#doInTransaction(org.springframework.transaction.TransactionStatus)
*/
public Object doInTransaction(TransactionStatus status) {
Result result = null;
try {
result = clazz.newInstance();
// 执行校验逻辑
action.check();
// 锁操作
action.doLock();
// 执行处理逻辑
result = action.executeService();
// 返回值异常处理
if (result == null || !(result instanceof Result)) {
throw new Exception();
}
} catch (Exception e) {//此处可换成具体异常或子定义异常
// 业务异常捕获, 回滚, 打日志TODO
LOG.error("Transfer Error！，"+e.getMessage());
status.setRollbackOnly();
return result;
} catch (Throwable e2) {
// 系统异常捕获, 回滚, 打日志TODO
LOG.error(e2.getMessage());
status.setRollbackOnly();
return result;
}
return result;
}
});
return acResult;
}
}
在业务方法中使用ServiceTemplate, 通过构建ServiceCallBack匿名内部类的方式, 传递具体的业务代码
OrdersService.java新增以下方法
public void addMoney() {
serviceTemplate.execute(Result.class, new ServiceCallback() {
@Override
public void doLock() {
// 进行锁操作
}
@Override
public void check() {
// 进行校验
}
@Override
public Result executeService() {
Result result = new Result();
// 具体的业务代码
// 小马多1000
ordersDao.addMoney();
// 加入出现异常如下面int
// i=10/0（银行中可能为突然停电等。。。）；结果：小马账户多了1000而小王账户没有少钱
// 解决办法是出现异常后进行事务回滚
int i = 10 / 0;// 事务管理配置后异常已经解决
// 小王 少1000
ordersDao.reduceMoney();
return result;
}
});
}修改beans.xml
<!-- 对象生成及属性注入 -->
<bean id="ordersService" class="com.gm.service.OrdersService">
<property name="ordersDao" ref="ordersDao"></property>
<!-- 注入事务管理的模板 -->
<property name="transactionTemplate" ref="transactionTemplate"></property>
<property name="serviceTemplate" ref="serviceTemplate"></property>
</bean>
<bean id="serviceTemplate" class="com.gm.service.ServiceTemplateImpl">
<!-- 注入事务管理的模板 -->
<property name="transactionTemplate" ref="transactionTemplate"></property>
</bean>修改TestService.java
public class TestService {
@Test
public void testAdd() {
ApplicationContext context = new ClassPathXmlApplicationContext("dbBeans.xml");
OrdersService userService = (OrdersService) context.getBean("ordersService");
//userService.accountMoney();
userService.addMoney();
}
}执行，输出
[ERROR] 2018-09-06 14:08:51,524 method:com.gm.service.ServiceTemplateImpl$1.doInTransaction(ServiceTemplateImpl.java:71)
Transfer Error！，/ by zero
注意: 如果是不需要加事务的方法, 如查询 ,那么调用serviceTemplate的executeWithoutTransaction即可
补充pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.test</groupId>
<artifactId>SpringTest</artifactId>
<version>0.0.1-SNAPSHOT</version>
<build />
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<!-- spring版本号 -->
<spring.version>4.1.5.RELEASE</spring.version>
<!-- mybatis版本号 -->
<mybatis.version>3.2.6</mybatis.version>
<!-- log4j日志文件管理包版本 -->
<slf4j.version>1.7.7</slf4j.version>
<log4j.version>1.2.17</log4j.version>
</properties>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<!-- 表示开发的时候引入，发布的时候不会加载此包 -->
<scope>test</scope>
</dependency>
<!-- spring核心包 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-oxm</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
</dependency>
<!-- aop -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.4</version>
</dependency>
<!-- mybatis核心包 -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>${mybatis.version}</version>
</dependency>
<!-- mybatis/spring包 -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.2.2</version>
</dependency>
<!-- 导入java ee jar 包 -->
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-api</artifactId>
<version>7.0</version>
</dependency>
<!-- 导入Mysql数据库链接jar包 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.30</version>
</dependency>
<!-- 导入dbcp的jar包，用来在applicationContext.xml中配置数据库 -->
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>1.2.2</version>
</dependency>
<!-- JSTL标签类 -->
<dependency>
<groupId>jstl</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<!-- 日志文件管理包 -->
<!-- log start -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>${log4j.version}</version>
</dependency>
<!-- 格式化对象，方便输出日志 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.1.41</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>${slf4j.version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>${slf4j.version}</version>
</dependency>
<!-- log end -->
<!-- 映入JSON -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.7.5</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.7.5</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.7.5</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>1.9.4</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-core-asl</artifactId>
<version>1.9.4</version>
</dependency>
<!-- 上传组件包 -->
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.1</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.4</version>
</dependency>
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.9</version>
</dependency>
<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2-adb</artifactId>
<version>1.6.3</version>
</dependency>
<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2-kernel</artifactId>
<version>1.6.3</version>
</dependency>
<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2-transport-local</artifactId>
<version>1.6.3</version>
</dependency>
<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2-transport-http</artifactId>
<version>1.6.3</version>
<exclusions>
<exclusion>
<artifactId>httpcore</artifactId>
<groupId>org.apache.httpcomponents</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.jdom</groupId>
<artifactId>jdom</artifactId>
<version>1.1.3</version>
</dependency>
<dependency>
<groupId>axis</groupId>
<artifactId>axis-jaxrpc</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>axis</groupId>
<artifactId>axis</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>org.freemarker</groupId>
<artifactId>freemarker</artifactId>
<version>2.3.23</version>
</dependency>
<dependency>
<groupId>org.codehaus.jettison</groupId>
<artifactId>jettison</artifactId>
<version>1.3.8</version>
</dependency>
<!--axis2 begin -->
<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2</artifactId>
<version>1.6.3</version>
</dependency>
<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2-spring</artifactId>
<version>1.6.3</version>
</dependency>
<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2-xmlbeans</artifactId>
<version>1.6.3</version>
</dependency>
<!--axis2 end -->
<dependency>
<groupId>org.kie.modules</groupId>
<artifactId>org-apache-commons-net</artifactId>
<version>6.4.0.Final</version>
<type>pom</type>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.2</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient-cache</artifactId>
<version>4.5.2</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpcore</artifactId>
<version>4.4.5</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpcore-nio</artifactId>
<version>4.4.5</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpcore-ab</artifactId>
<version>4.4.5</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.eclipse.paho/org.eclipse.paho.client.mqttv3 -->
<dependency>
<groupId>org.eclipse.paho</groupId>
<artifactId>org.eclipse.paho.client.mqttv3</artifactId>
<version>1.2.0</version>
</dependency>
<!-- oracle数据库驱动 -->
<dependency>
<groupId>oracle.driver</groupId>
<artifactId>oracle-driver</artifactId>
<version>11.2.0.4</version>
</dependency>
<dependency>
<groupId>dom4j</groupId>
<artifactId>dom4j</artifactId>
<version>1.6.1</version>
</dependency>
<dependency>
<groupId>net.sf.json-lib</groupId>
<artifactId>json-lib</artifactId>
<version>2.4</version>
<classifier>jdk15</classifier>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.2</version>
</dependency>
</dependencies>
</project>
