18.Spring中基于事务控制纯注解的配置（转账）

1.结构图

 2.实体类Account：

package com.itheima.pojo;

public class Account {
    private Integer id;
    private String name;
    private Float 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 Float getMoney() {
        return money;
    }

    public void setMoney(Float money) {
        this.money = money;
    }

    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", money=" + money +
                '}';
    }
}

3.业务层接口IAccountService：

package com.itheima.service;

import com.itheima.pojo.Account;

//业务层接口
public interface IAccountService {
    //根据id查询
    Account findAccountById(Integer accountId);
    //转账
    void transfer(String sourceName, String targetName, Float money);
}

4.业务层实现类AccountServiceImpl：

package com.itheima.service.impl;

import com.itheima.dao.IAccountDao;
import com.itheima.pojo.Account;
import com.itheima.service.IAccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

//业务层实现类
@Service("accountService")
@Transactional(propagation = Propagation.SUPPORTS,readOnly = true)//只读型事务
public class AccountServiceImpl implements IAccountService {
    @Autowired
    private IAccountDao accountDao;

    @Override
    public Account findAccountById(Integer accountId) {
        return accountDao.findAccountById(accountId);
    }
    @Transactional(propagation = Propagation.REQUIRED,readOnly = false)//这里需要读写型事务
    @Override
    public void transfer(String sourceName, String targetName, Float money) {
        //1.根据转出账户
        Account source = accountDao.findAccountByName(sourceName);
        //2.根据转入账户
        Account target = accountDao.findAccountByName(targetName);
        //3.转出账户减钱
        source.setMoney(source.getMoney()-money);
        //4.转入账户加钱
        target.setMoney(target.getMoney()+money);
        // int i = 1/0;
        //5.更新保存转出账户
        accountDao.updateAccount(source);
        //6.更新保存转入账户
        accountDao.updateAccount(target);
    }
    /*这里使用的事务不一样导致每使用一次配一次注解：所以最好的还是使用纯的XML配置*/
}

 5.持久层接口IAccountDao：

package com.itheima.dao;

import com.itheima.pojo.Account;

//持久层接口
public interface IAccountDao {
    //根据id查询
    Account findAccountById(Integer accountId);
    //根据名称查询
    Account findAccountByName(String accountName);
    //更新操作
    void updateAccount(Account account);
}
6.持久层实现类AccountDaoImpl：

package com.itheima.dao.impl;

import com.itheima.dao.IAccountDao;
import com.itheima.pojo.Account;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import java.util.List;

//持久层实现类
@Repository("accountDao")
public class AccountDaoImpl implements IAccountDao {
    @Autowired
    //配置模版，加了继承使用不了注解
    private JdbcTemplate jdbcTemplate;

    //按id查询(return accounts.isEmpty()?null:accounts.get(0);id的结果只有一个，查来查去只有一个，所以能使用这种方法)
    @Override
    public Account findAccountById(Integer accountId) {
   List<Account> accounts = jdbcTemplate.query("select * from account where id = ?",new BeanPropertyRowMapper<Account>(Account.class),accountId);
        return accounts.isEmpty()?null:accounts.get(0);
        /*//第二种抽取代码块之后
        List<Account> accounts = super.getJdbcTemplate().query("select * from account where id = ?",new BeanPropertyRowMapper<Account>(Account.class),accountId);
        return accounts.isEmpty()?null:accounts.get(0);*/
    }
    //这个名字能有多个
    @Override
    public Account findAccountByName(String accountName) {
        //未抽取代码块之前
        List<Account> accounts =  jdbcTemplate.query("select * from account where name = ?",new BeanPropertyRowMapper<Account>(Account.class),accountName);
       /* List<Account> accounts = super.getJdbcTemplate().query("select * from account where name = ?",new BeanPropertyRowMapper<Account>(Account.class),accountName);*/
        if (accounts.isEmpty()){
            return null;
        }if (accounts.size()>1){
            throw new RuntimeException("结果集不唯一");
        }
        return accounts.get(0);
    }
    //更新账户
    @Override
    public void updateAccount(Account account) {
        jdbcTemplate.update("update account set name=?,money=? where  id=?",account.getName(),account.getMoney(),account.getId());
        //使用第二种方法：抽取代码块
        /*super.getJdbcTemplate().update("update account set name=?,money=? where  id=?",account.getName(),account.getMoney(),account.getId());*/
        /*jdbcTemplate.update("update account set name=?,money=? where  id=?",account.getName(),account.getMoney(),account.getId());*/
    }
}

7.主配置类SpringConfiguration（注解的理解）：

package com.itheima.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的配置类，相当于bean.xml
* */
//开启spring配置类
@Configuration
//扫描包
@ComponentScan("com.itheima")
//配置数据库类
@Import({JdbcConfig.class,TransactionConfig.class})
//引入数据库资源
@PropertySource("jdbcConfig.properties")
//事务管理:开启事务的注解支持：<tx:annotation-driven transaction-manager="transactionManager"></tx:annotation-driven>
@EnableTransactionManagement
public class SpringConfiguration {
}

8.事务相关的配置类TransactionConfig（引入主类）：

package com.itheima.config;


import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;

import javax.sql.DataSource;

/*
* 和事务相关的配置类
* */
public class TransactionConfig {
    /*
    * 用于创建事务管理器对象
    * */
    @Bean(name = "transactionManager")
    public PlatformTransactionManager createTransactionManager(DataSource dataSource){
        return new DataSourceTransactionManager(dataSource);
    }
}

9.连接上数据库的配置类JdbcConfig:

package com.itheima.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;

/*
* 和连接数据库相关的配置类
* */
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;
    /*
    * 创建JdbcTemplate
    * */
    @Bean(name = "jdbcTemplate")
    public JdbcTemplate createJdbcTemplate(DataSource dataSource){
        return  new JdbcTemplate(dataSource);
    }
    /*
    * 创建数据库对象
    * */
    @Bean(name = "dataSource")
    public DataSource createDataSource(){
        DriverManagerDataSource ds = new DriverManagerDataSource();
        ds.setDriverClassName(driver);
        ds.setUrl(url);
        ds.setUsername(username);
        ds.setPassword(password);
        return ds;
    }
}

10.jdbcConfig.properties配置数据库连接

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/eesy
jdbc.username=root
jdbc.password=123456

11.pom文件

<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>

    <!-- jdbc模版依赖-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
    <!-- spring环境依赖-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
    <!-- 事务依赖-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
    <!-- 连接数据库的依赖-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.6</version>
        <scope>runtime</scope>
    </dependency>
    <!--aop依赖-->
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.8.7</version>
    </dependency>
    <!--整合依赖-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
</dependencies>

12.TestCode

package com.itheima;
import com.itheima.config.SpringConfiguration;
import com.itheima.service.IAccountService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
@RunWith(SpringJUnit4ClassRunner.class)
/*说明位置*/
@ContextConfiguration(classes = SpringConfiguration.class)
/*pom.xml加上spring-test依赖*/
public class TestCode {
    @Autowired
    /*在这个时候：就有两个AccountService，通过@Qualifier来指定名称*/
    //@Qualifier("proxyAccountService")
    //@Resource(name="proxyAccountService")
    /*这时候当然也可以用@Resource替换上面两个，但是需要导入相关依赖，否则会报空指针异常*/
    private IAccountService as;
    @Test
    public void testTransfer(){
        as.transfer("test","zhou",1000f);
    }
}