spring基于純注解的聲明式事務控制(*)
了解即可，真實項目中不建議使用這種方式
一售碳、純注解配置步驟
1). 配置數據庫連接信息jdbcConfig.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/spring_01
jdbc.username=root
jdbc.password=abc123
2). 配置jdbcConfig jdbcTemplate與數據源
DataSourceTransactionManager類中有個屬性nestedTransactionAllowed ，表示允許【嵌套事務】星澳，基于此原理滞谢，然后再基于切面編程(被代理方法前后增強)，實現(xiàn)嵌套事務粥庄！
package config;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import javax.sql.DataSource;
/**
* 和連接數據庫相關的配置類
*/
public class JdbcConfig {
@Value("${jdbc.driver}")
private String driver;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String username;
@Value("${jdbc.password}")
private String password;
@Bean(name = "jdbcTemplate")
public JdbcTemplate createJdbcTemplate(DataSource dataSource) {
return new JdbcTemplate(dataSource);
}
@Bean(name="dataSource")
public DataSource createDataSource() {
DriverManagerDataSource ds = new DriverManagerDataSource();
ds.setDriverClassName(driver);
ds.setUrl(url);
ds.setUsername(username);
ds.setPassword(password);
return ds;
}
}
3). 配置 事務管理器TransactionConfig --- 切面
package config;
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import javax.sql.DataSource;
/**
* 和事務相關的配置類
*/
public class TransactionConfig {
/** 創(chuàng)建事務管理器對象 */
@Bean(name="transactionManager")
public PlatformTransactionManager createTransactionManager(DataSource dataSource) {
return new DataSourceTransactionManager(dataSource);
}
}
4). 配置綜合配置類SpringConfiguration
相當于applicationContext.xml;其中@EnableTransactionManagement表示開啟事務
package config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.PropertySource;
import org.springframework.transaction.annotation.EnableTransactionManagement;
/**
* spring的配置類，相當于applicationContext.xml
*/
@Configuration
@ComponentScan("com.itheima")
@Import({JdbcConfig.class,TransactionConfig.class})
@PropertySource("jdbcConfig.properties")
@EnableTransactionManagement // 開啟事務
public class SpringConfiguration {
}
二衫樊、項目其他源代碼
1). 項目結構
spring基于純注解的聲明式事務控制.png
2). Account pojo
省略get/set/toString方法
public class Account {
private Integer id;
private String name;
private Float money;
...
3). MyJdbcDaoSupport 抽離的jdbcTemplate
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;
/** 如果使用注解開發(fā)飒赃，需要自己抽離JdbcTemplate */
@Component("myJdbcDaoSupport")
public class MyJdbcDaoSupport {
// 下面這部分就需要在配置文件中進行配置
@Autowired
private JdbcTemplate jdbcTemplate;
public JdbcTemplate getJdbcTemplate() {
return jdbcTemplate;
}
}
4). dao持久層
import com.itheima.domain.Account;
import java.sql.SQLException;
public interface AccountDao {
/** 根據id查詢賬戶的余額 */
public Account queryMoney(Integer id) throws SQLException;
/** 根據id更新賬戶的余額 */
public int updateMoney(Integer id, Float money) throws SQLException;
}
import com.itheima.dao.AccountDao;
import com.itheima.domain.Account;
import com.itheima.utils.MyJdbcDaoSupport;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.stereotype.Repository;
import java.sql.SQLException;
@Repository("accountDao")
public class AccountDaoImpl extends MyJdbcDaoSupport implements AccountDao {
/** @事務
* 根據id查詢賬戶的余額利花，將異常顯示拋出 */
@Override
public Account queryMoney(Integer id) throws SQLException {
return super.getJdbcTemplate().queryForObject("select money from account where id = ?",
new BeanPropertyRowMapper<Account>(Account.class), id);
}
/** @事務
* 根據id更新賬戶的余額, 將異常顯示拋出 */
@Override
public int updateMoney(Integer id, Float money) throws SQLException {
return super.getJdbcTemplate().update("update account set money = ? where id = ?",
money, id);
}
}
5). service業(yè)務層
public interface AccountService {
/** 轉賬業(yè)務 */
public boolean transfer(Integer fromId, Integer toId, Float money) throws Exception;
}
package com.itheima.service.impl;
import com.itheima.dao.AccountDao;
import com.itheima.domain.Account;
import com.itheima.service.AccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
@Service("accountService")
@Transactional(propagation = Propagation.SUPPORTS, readOnly = true)
public class AccountServiceImpl implements AccountService {
@Autowired
private AccountDao accountDao;
/** @事務
* 轉賬業(yè)務 使用注解進行聲明式事務處理科侈，使用
* @Transactional 注解载佳，并在其中配置參數*/
@Override
@Transactional(propagation = Propagation.SUPPORTS, readOnly = false)
public boolean transfer(Integer fromId, Integer toId, Float money) throws Exception {
// 1. 查詢原賬戶余額
Account fromMoney = accountDao.queryMoney(fromId);
if (fromMoney.getMoney() < money) {
throw new RuntimeException("賬戶余額不足，無法完成轉賬");
}
// 2. 查詢被轉入賬戶的余額
Account toMoney = accountDao.queryMoney(toId);
// 3. 扣除原賬戶的money
accountDao.updateMoney(fromId, fromMoney.getMoney() - money);
// 顯示拋出一個異常臀栈。
//int a = 8 / 0;
// 4. 添加被轉入賬戶的余額
accountDao.updateMoney(toId, toMoney.getMoney() + money);
return true;
}
}
6). Junit4測試代碼
import config.SpringConfiguration;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = SpringConfiguration.class)
public class MyTest {
@Autowired
private ApplicationContext ac;
/** 轉賬測試 */
@Test
public void testTransfer() throws Exception {
AccountService service = (AccountService)ac.getBean("accountService");
boolean res = service.transfer(4, 2, 1000F);
System.out.println(res);
}
}
7). maven工程坐標
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.41</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-expression</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.0.2.RELEASE</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<!-- 切入點表達式解析的jar包 -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.7</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.0.2.RELEASE</version>
</dependency>
</dependencies>
