#编程式事务控制#TransactionTemplate#[email protected]
测试环境:IDEA 2020.2、MySQL 8.0.16
项目结构:
pom.xml的内容:
<?xml version="1.0" encoding="UTF-8"?> <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>org.example</groupId> <artifactId>P041_programmatic_transaction_control</artifactId> <version>1.0-SNAPSHOT</version> <dependencies> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>5.1.8.RELEASE</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.16</version> </dependency> <!--连接池--> <dependency> <groupId>com.mchange</groupId> <artifactId>c3p0</artifactId> <version>0.9.5.2</version> </dependency> <!--单元测试--> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>5.1.8.RELEASE</version> </dependency> </dependencies> </project>
bean.xml的内容:
<?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:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop.xsd"> <!--ComboPooledDataSource只能通过set方法(property标签)注入连接相关的信息--> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" scope="singleton"> <property name="driverClass" value="com.mysql.cj.jdbc.Driver"></property> <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/test?characterEncoding=UTF8&serverTimezone=Asia/Shanghai"></property> <property name="user" value="root"></property> <property name="password" value="123456"></property> </bean> <bean class="org.springframework.jdbc.datasource.DataSourceTransactionManager" id="transactionManager"> <property name="dataSource" ref="dataSource"></property> </bean> <bean class="org.springframework.transaction.support.TransactionTemplate" id="transactionTemplate"> <property name="transactionManager" ref="transactionManager"></property> </bean> <bean class="org.springframework.jdbc.core.JdbcTemplate" id="jdbcTemplate"> <property name="dataSource" ref="dataSource"></property> </bean> <bean class="cn.liuxingchang.Dao.impl.AccountDaoImpl" id="accountDao"> <property name="jdbcTemplate" ref="jdbcTemplate"></property> </bean> <bean id="accountService" class="cn.liuxingchang.service.impl.AccountServiceImpl"> <property name="accountDao" ref="accountDao"></property> <property name="transactionTemplate" ref="transactionTemplate"></property> </bean> </beans>
MySQL数据库:
database:test port:3306 table:account
Account.java的内容:
package cn.liuxingchang.Domain; import java.io.Serializable; public class Account implements Serializable { private Integer id; private String name; private Double money; 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 Double getMoney() { return money; } public void setMoney(Double money) { this.money = money; } @Override public String toString() { return "Account{" + "id=" + id + ", name='" + name + '\'' + ", money=" + money + '}'; } }
AccountDao.java的内容:
package cn.liuxingchang.Dao; import cn.liuxingchang.Domain.Account; public interface AccountDao { void updateAccount(Account account); Account findAccountByName(String name); }
AccountDaoImpl.java的内容:
package cn.liuxingchang.Dao.impl; import cn.liuxingchang.Dao.AccountDao; import cn.liuxingchang.Domain.Account; import org.springframework.jdbc.core.BeanPropertyRowMapper; import org.springframework.jdbc.core.JdbcTemplate; import java.util.List; public class AccountDaoImpl implements AccountDao { private JdbcTemplate jdbcTemplate; public void setJdbcTemplate(JdbcTemplate jdbcTemplate) { this.jdbcTemplate = jdbcTemplate; } public void updateAccount(Account account) { try { jdbcTemplate.update("update account set name = ?, money = ? where id = ?", account.getName(), account.getMoney(), account.getId()); } catch(Exception e) { throw new RuntimeException(e); } } public Account findAccountByName(String name) { try { List<Account> accounts = jdbcTemplate.query("select * from account where name = ?", new BeanPropertyRowMapper<Account>(Account.class), name); if(accounts == null || accounts.size() == 0) { throw new RuntimeException("找不到目标账户!"); } else if(accounts.size() == 1) { return accounts.get(0); } else { throw new RuntimeException("账户不唯一!"); } } catch (Exception e) { throw new RuntimeException(e); } } }
AccountService.java的内容:
package cn.liuxingchang.service; public interface AccountService { void transfer(String sourceName, String targetName, Double money); }
AccountServiceImpl.java的内容:
package cn.liuxingchang.service.impl; import cn.liuxingchang.Dao.AccountDao; import cn.liuxingchang.Domain.Account; import cn.liuxingchang.service.AccountService; import org.springframework.transaction.TransactionStatus; import org.springframework.transaction.support.TransactionCallback; import org.springframework.transaction.support.TransactionTemplate; public class AccountServiceImpl implements AccountService { private AccountDao accountDao; public void setAccountDao(AccountDao accountDao) { this.accountDao = accountDao; } private TransactionTemplate transactionTemplate; public void setTransactionTemplate(TransactionTemplate transactionTemplate) { this.transactionTemplate = transactionTemplate; } public void transfer(final String sourceName, final String targetName, final Double money) { transactionTemplate.execute(new TransactionCallback<Object>() { public Object doInTransaction(TransactionStatus transactionStatus) { Account source = accountDao.findAccountByName(sourceName); Account target = accountDao.findAccountByName(targetName); source.setMoney(source.getMoney() - money); target.setMoney(target.getMoney() + money); accountDao.updateAccount(source); int i = 1 / 0; //用来测试事务的一致性 accountDao.updateAccount(target); return null; } }); } }
Test.java的内容:
import cn.liuxingchang.service.AccountService; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class Test { ApplicationContext context = new ClassPathXmlApplicationContext("bean.xml"); AccountService accountService = context.getBean("accountService", AccountService.class); @org.junit.Test public void transferTest() { accountService.transfer("Zhao", "Qian", 1.0); } }