JdbcTemplate

JdbcTemplate 概述

它是 spring 框架中提供的一个对象，是对原始 Jdbc API 对象的简单封装。spring 框架为我们提供了很多的操作模板类。

• 操作关系型数据的：JdbcTemplate，HibernateTemplate

• 操作 nosql 数据库的：RedisTemplate

• 操作消息队列的：JmsTemplate

JdbcTemplate 对象的创建

我们可以参考它的源码，来一探究竟：

public JdbcTemplate() {
}

public JdbcTemplate(DataSource dataSource) {
    this.setDataSource(dataSource);
    this.afterPropertiesSet();
}

public JdbcTemplate(DataSource dataSource, boolean lazyInit) {
    this.setDataSource(dataSource);
    this.setLazyInit(lazyInit);
    this.afterPropertiesSet();
}

除了默认构造函数之外，都需要提供一个数据源。既然有set方法，依据我们之前学过的依赖注入，我们可以在配置文件中配置这些对象。

JdbcTemplate基本使用

1.首先导入依赖如下：

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
    <!--JdbcTemplate依赖 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
    
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.6</version>
    </dependency>
</dependencies>

2.编写 spring 的配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!-- 配置账户的持久层-->
    <bean id="accountDao" class="com.itheima.dao.impl.AccountDaoImpl">
        <!--<property name="jdbcTemplate" ref="jdbcTemplate"></property>-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!--配置JdbcTemplate -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!-- 配置spring 内置数据源-->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/eesy"></property>
        <property name="username" value="root"></property>
        <property name="password" value="1234"></property>
    </bean>
</beans>

3.编写持久层代码如下：

/**
 * 账户的持久层接口
 */
public interface IAccountDao {

    /**
     * 根据Id查询账户
     * @param accountId
     * @return
     */
    Account findAccountById(Integer accountId);

    /**
     * 根据名称查询账户
     * @param accountName
     * @return
     */
    Account findAccountByName(String accountName);

    /**
     * 更新账户
     * @param account
     */
    void updateAccount(Account account);
}

/**
 * 账户的持久层实现类
 */
@Repository
public class AccountDaoImpl implements IAccountDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;


    @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);
    }

    @Override
    public Account findAccountByName(String accountName) {
        List<Account> accounts = jdbcTemplate.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);
    }

    @Override
    public void updateAccount(Account account) {
        jdbcTemplate.update("update account set name=?,money=? where id=?",account.getName(),account.getMoney(),account.getId());
    }
}

4.测试类如下：

/**
 * JdbcTemplate的最基本用法
 */
public class JdbcTemplateDemo4 {

    public static void main(String[] args) {
        //1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml");
        //2.获取对象
        IAccountDao accountDao = ac.getBean("accountDao",IAccountDao.class);

        Account account = accountDao.findAccountById(1);
        System.out.println(account);

        account.setMoney(30000f);
        accountDao.updateAccount(account);
    }
}

Spring事务控制

使用AOP事务控制

基于xml的AOP事务控制

1.首先导入依赖如下：

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>commons-dbutils</groupId>
        <artifactId>commons-dbutils</artifactId>
        <version>1.4</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.6</version>
    </dependency>

    <dependency>
        <groupId>c3p0</groupId>
        <artifactId>c3p0</artifactId>
        <version>0.9.1.2</version>
    </dependency>

    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
    </dependency>
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.8.7</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>
</dependencies>

2.编写数据库连接工具如下：

/**
 * 连接的工具类，它用于从数据源中获取一个连接，并且实现和线程的绑定
 */
public class ConnectionUtils {

    private ThreadLocal<Connection> tl = new ThreadLocal<Connection>();

    private DataSource dataSource;

    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }

    /**
     * 获取当前线程上的连接
     * @return
     */
    public Connection getThreadConnection() {
        try{
            //1.先从ThreadLocal上获取
            Connection conn = tl.get();
            //2.判断当前线程上是否有连接
            if (conn == null) {
                //3.从数据源中获取一个连接，并且存入ThreadLocal中
                conn = dataSource.getConnection();
                tl.set(conn);
            }
            //4.返回当前线程上的连接
            return conn;
        }catch (Exception e){
            throw new RuntimeException(e);
        }
    }

    /**
     * 把连接和线程解绑
     */
    public void removeConnection(){
        tl.remove();
    }
}

3.编写事务控制类如下：

/**
 * 和事务管理相关的工具类，它包含了，开启事务，提交事务，回滚事务和释放连接
 */
public class TransactionManager {

    private ConnectionUtils connectionUtils;

    public void setConnectionUtils(ConnectionUtils connectionUtils) {
        this.connectionUtils = connectionUtils;
    }

    /**
     * 开启事务
     */
    public  void beginTransaction(){
        try {
            connectionUtils.getThreadConnection().setAutoCommit(false);
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    /**
     * 提交事务
     */
    public  void commit(){
        try {
            connectionUtils.getThreadConnection().commit();
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    /**
     * 回滚事务
     */
    public  void rollback(){
        try {
            connectionUtils.getThreadConnection().rollback();
        }catch (Exception e){
            e.printStackTrace();
        }
    }


    /**
     * 释放连接
     */
    public  void release(){
        try {
            connectionUtils.getThreadConnection().close();//还回连接池中
            connectionUtils.removeConnection();
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}

4.编写dao 层

/**
 * 账户的持久层接口
 */
public interface IAccountDao {

    /**
     * 查询所有
     * @return
     */
    List<Account> findAllAccount();

    /**
     * 查询一个
     * @return
     */
    Account findAccountById(Integer accountId);

    /**
     * 保存
     * @param account
     */
    void saveAccount(Account account);

    /**
     * 更新
     * @param account
     */
    void updateAccount(Account account);

    /**
     * 删除
     * @param acccountId
     */
    void deleteAccount(Integer acccountId);

    /**
     * 根据名称查询账户
     * @param accountName
     * @return  如果有唯一的一个结果就返回，如果没有结果就返回null
     *          如果结果集超过一个就抛异常
     */
    Account findAccountByName(String accountName);
}

/**
 * 账户的持久层实现类
 */
public class AccountDaoImpl implements IAccountDao {

    private QueryRunner runner;
    private ConnectionUtils connectionUtils;

    public void setRunner(QueryRunner runner) {
        this.runner = runner;
    }

    public void setConnectionUtils(ConnectionUtils connectionUtils) {
        this.connectionUtils = connectionUtils;
    }

    @Override
    public List<Account> findAllAccount() {
        try{
            return runner.query(connectionUtils.getThreadConnection(),"select * from account",new BeanListHandler<Account>(Account.class));
        }catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public Account findAccountById(Integer accountId) {
        try{
            return runner.query(connectionUtils.getThreadConnection(),"select * from account where id = ? ",new BeanHandler<Account>(Account.class),accountId);
        }catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void saveAccount(Account account) {
        try{
            runner.update(connectionUtils.getThreadConnection(),"insert into account(name,money)values(?,?)",account.getName(),account.getMoney());
        }catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void updateAccount(Account account) {
        try{
            runner.update(connectionUtils.getThreadConnection(),"update account set name=?,money=? where id=?",account.getName(),account.getMoney(),account.getId());
        }catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void deleteAccount(Integer accountId) {
        try{
            runner.update(connectionUtils.getThreadConnection(),"delete from account where id=?",accountId);
        }catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public Account findAccountByName(String accountName) {
        try{
            List<Account> accounts = runner.query(connectionUtils.getThreadConnection(),"select * from account where name = ? ",new BeanListHandler<Account>(Account.class),accountName);
            if(accounts == null || accounts.size() == 0){
                return null;
            }
            if(accounts.size() > 1){
                throw new RuntimeException("结果集不唯一，数据有问题");
            }
            return accounts.get(0);
        }catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}

5.编写service层

/**
 * 账户的业务层接口
 */
public interface IAccountService {

    /**
     * 查询所有
     * @return
     */
    List<Account> findAllAccount();

    /**
     * 查询一个
     * @return
     */
    Account findAccountById(Integer accountId);

    /**
     * 保存
     * @param account
     */
    void saveAccount(Account account);

    /**
     * 更新
     * @param account
     */
    void updateAccount(Account account);

    /**
     * 删除
     * @param acccountId
     */
    void deleteAccount(Integer acccountId);

    /**
     * 转账
     * @param sourceName        转出账户名称
     * @param targetName        转入账户名称
     * @param money             转账金额
     */
    void transfer(String sourceName,String targetName,Float money);

    //void test();//它只是连接点，但不是切入点，因为没有被增强
}

/**
 * 账户的业务层实现类
 *
 * 事务控制应该都是在业务层
 */
public class AccountServiceImpl implements IAccountService{

    private IAccountDao accountDao;

    public void setAccountDao(IAccountDao accountDao) {
        this.accountDao = accountDao;
    }

    @Override
    public List<Account> findAllAccount() {
       return accountDao.findAllAccount();
    }

    @Override
    public Account findAccountById(Integer accountId) {
        return accountDao.findAccountById(accountId);

    }

    @Override
    public void saveAccount(Account account) {
        accountDao.saveAccount(account);
    }

    @Override
    public void updateAccount(Account account) {
        accountDao.updateAccount(account);
    }

    @Override
    public void deleteAccount(Integer acccountId) {
        accountDao.deleteAccount(acccountId);
    }

    @Override
    public void transfer(String sourceName, String targetName, Float money) {
        System.out.println("transfer....");
            //2.1根据名称查询转出账户
            Account source = accountDao.findAccountByName(sourceName);
            //2.2根据名称查询转入账户
            Account target = accountDao.findAccountByName(targetName);
            //2.3转出账户减钱
            source.setMoney(source.getMoney()-money);
            //2.4转入账户加钱
            target.setMoney(target.getMoney()+money);
            //2.5更新转出账户
            accountDao.updateAccount(source);

//            int i=1/0;

            //2.6更新转入账户
            accountDao.updateAccount(target);
    }
}

6.编写spring配置文件如下：

<?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
        http://www.springframework.org/schema/aop/spring-aop.xsd">

     <!-- 配置Service -->
    <bean id="accountService" class="com.itheima.service.impl.AccountServiceImpl">
        <!-- 注入dao -->
        <property name="accountDao" ref="accountDao"></property>
    </bean>

    <!--配置Dao对象-->
    <bean id="accountDao" class="com.itheima.dao.impl.AccountDaoImpl">
        <!-- 注入QueryRunner -->
        <property name="runner" ref="runner"></property>
        <!-- 注入ConnectionUtils -->
        <property name="connectionUtils" ref="connectionUtils"></property>
    </bean>

    <!--配置QueryRunner-->
    <bean id="runner" class="org.apache.commons.dbutils.QueryRunner" scope="prototype"></bean>

    <!-- 配置数据源 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!--连接数据库的必备信息-->
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/eesy"></property>
        <property name="user" value="root"></property>
        <property name="password" value="1234"></property>
    </bean>

    <!-- 配置Connection的工具类 ConnectionUtils -->
    <bean id="connectionUtils" class="com.itheima.utils.ConnectionUtils">
        <!-- 注入数据源-->
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!-- 配置事务管理器-->
    <bean id="txManager" class="com.itheima.utils.TransactionManager">
        <!-- 注入ConnectionUtils -->
        <property name="connectionUtils" ref="connectionUtils"></property>
    </bean>

    <!--配置aop-->
    <aop:config>
        <!--配置通用切入点表达式-->
        <aop:pointcut id="pt1" expression="execution(* com.itheima.service.impl.*.*(..))"></aop:pointcut>
        <aop:aspect id="txAdvice" ref="txManager">
            <!--配置前置通知：开启事务-->
            <aop:before method="beginTransaction" pointcut-ref="pt1"></aop:before>
            <!--配置后置通知：提交事务-->
            <aop:after-returning method="commit" pointcut-ref="pt1"></aop:after-returning>
            <!--配置异常通知：回滚事务-->
            <aop:after-throwing method="rollback" pointcut-ref="pt1"></aop:after-throwing>
            <!--配置最终通知：释放连接-->
            <aop:after method="release" pointcut-ref="pt1"></aop:after>
        </aop:aspect>
    </aop:config>
</beans>

7.测试类如下：

/**
 * 使用Junit单元测试：测试我们的配置
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:bean.xml")
public class AccountServiceTest {

    @Autowired
    private  IAccountService as;

    @Test
    public  void testTransfer(){
        as.transfer("aaa","bbb",100f);

    }
}

基于注解的AOP事务控制

1.spring配置文件中配置数据源以及开启spring对Aop注解的支持如下：

<?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"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <!--配置spring创建容器时要扫描的包-->
    <context:component-scan base-package="com.itheima"></context:component-scan>


    <!--配置QueryRunner-->
    <bean id="runner" class="org.apache.commons.dbutils.QueryRunner" scope="prototype"></bean>

    <!-- 配置C3P0数据源 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!--连接数据库的必备信息-->
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/eesy"></property>
        <property name="user" value="root"></property>
        <property name="password" value="1234"></property>
    </bean>

   <!--开启spring对注解AOP的支持-->
    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>
</beans>

2.数据库连接工具类修改如下：

/**
 * 连接的工具类，它用于从数据源中获取一个连接，并且实现和线程的绑定
 */
@Component("connectionUtils")
public class ConnectionUtils {

    private ThreadLocal<Connection> tl = new ThreadLocal<Connection>();

    @Autowired
    private DataSource dataSource;


    /**
     * 获取当前线程上的连接
     * @return
     */
    public Connection getThreadConnection() {
        try{
            //1.先从ThreadLocal上获取
            Connection conn = tl.get();
            //2.判断当前线程上是否有连接
            if (conn == null) {
                //3.从数据源中获取一个连接，并且存入ThreadLocal中
                conn = dataSource.getConnection();
                tl.set(conn);
            }
            //4.返回当前线程上的连接
            return conn;
        }catch (Exception e){
            throw new RuntimeException(e);
        }
    }

    /**
     * 把连接和线程解绑
     */
    public void removeConnection(){
        tl.remove();
    }
}

3.事务管理类如下：

/**
 * 和事务管理相关的工具类，它包含了，开启事务，提交事务，回滚事务和释放连接
 */
@Component("txManager")
@Aspect
public class TransactionManager {

    @Autowired
    private ConnectionUtils connectionUtils;

    @Pointcut("execution(* com.itheima.service.impl.*.*(..))")
    private void pt1(){}


    /**
     * 开启事务
     */
    public  void beginTransaction(){
        try {
            connectionUtils.getThreadConnection().setAutoCommit(false);
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    /**
     * 提交事务
     */
    public  void commit(){
        try {
            connectionUtils.getThreadConnection().commit();
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    /**
     * 回滚事务
     */
    public  void rollback(){
        try {
            connectionUtils.getThreadConnection().rollback();
        }catch (Exception e){
            e.printStackTrace();
        }
    }


    /**
     * 释放连接
     */
    public  void release(){
        try {
            connectionUtils.getThreadConnection().close();//还回连接池中
            connectionUtils.removeConnection();
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    @Around("pt1()")
    public Object aroundAdvice(ProceedingJoinPoint pjp){
        Object rtValue = null;
        try {
            //1.获取参数
            Object[] args = pjp.getArgs();
            //2.开启事务
            this.beginTransaction();
            //3.执行方法
            rtValue = pjp.proceed(args);
            //4.提交事务
            this.commit();

            //返回结果
            return  rtValue;

        }catch (Throwable e){
            //5.回滚事务
            this.rollback();
            throw new RuntimeException(e);
        }finally {
            //6.释放资源
            this.release();
        }
    }
}

其余类似

Spring 中事务控制的API介绍

PlatformTransactionManager

此接口是 spring 的事务管理器，它里面提供了我们常用的操作事务的方法，如下图： 我们在开发中都是使用它的实现类，如下：

• 使用 Spring JDBC 或 iBatis 进行持久化数据时使用：org.springframework.jdbc.datasource.DataSourceTransactionManager

• 使用Hibernate 版本进行持久化数据时使用：org.springframework.orm.hibernate5.HibernateTransactionManager

TransactionDefinition

它是事务的定义信息对象，里面有如下方法：

事务的隔离级别

事务的传播行为

基于 XML 的声明式事务控制

1.首先引入依赖

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <!--spring事务依赖-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.6</version>
    </dependency>

    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.8.7</version>
    </dependency>

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

2.dao层代码如下：

/**
 * 账户的持久层接口
 */
public interface IAccountDao {

    /**
     * 根据Id查询账户
     * @param accountId
     * @return
     */
    Account findAccountById(Integer accountId);

    /**
     * 根据名称查询账户
     * @param accountName
     * @return
     */
    Account findAccountByName(String accountName);

    /**
     * 更新账户
     * @param account
     */
    void updateAccount(Account account);
}

/**
 * 账户的持久层实现类
 */
public class AccountDaoImpl extends JdbcDaoSupport implements IAccountDao {

    @Override
    public Account findAccountById(Integer accountId) {
        List<Account> accounts = super.getJdbcTemplate().query("select * from account where id = ?",new BeanPropertyRowMapper<Account>(Account.class),accountId);
        return accounts.isEmpty()?null:accounts.get(0);
    }

    @Override
    public Account findAccountByName(String 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);
    }

    @Override
    public void updateAccount(Account account) {
        super.getJdbcTemplate().update("update account set name=?,money=? where id=?",account.getName(),account.getMoney(),account.getId());
    }
}

3.service层代码如下：

/**
 * 账户的业务层接口
 */
public interface IAccountService {
    /**
     * 根据id查询账户信息
     * @param accountId
     * @return
     */
    Account findAccountById(Integer accountId);

    /**
     * 转账
     * @param sourceName    转成账户名称
     * @param targetName    转入账户名称
     * @param money         转账金额
     */
    void transfer(String sourceName,String targetName,Float money);
}

**
 * 账户的业务层实现类
 *
 * 事务控制应该都是在业务层
 */
public class AccountServiceImpl implements IAccountService{

    private IAccountDao accountDao;

    public void setAccountDao(IAccountDao accountDao) {
        this.accountDao = accountDao;
    }

    @Override
    public Account findAccountById(Integer accountId) {
        return accountDao.findAccountById(accountId);

    }



    @Override
    public void transfer(String sourceName, String targetName, Float money) {
        System.out.println("transfer....");
            //2.1根据名称查询转出账户
            Account source = accountDao.findAccountByName(sourceName);
            //2.2根据名称查询转入账户
            Account target = accountDao.findAccountByName(targetName);
            //2.3转出账户减钱
            source.setMoney(source.getMoney()-money);
            //2.4转入账户加钱
            target.setMoney(target.getMoney()+money);
            //2.5更新转出账户
            accountDao.updateAccount(source);

            int i=1/0;

            //2.6更新转入账户
            accountDao.updateAccount(target);
    }
}

4.spring配置文件中配置事务如下：

<?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"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">

    <!-- 配置业务层-->
    <bean id="accountService" class="com.itheima.service.impl.AccountServiceImpl">
        <property name="accountDao" ref="accountDao"></property>
    </bean>

    <!-- 配置账户的持久层-->
    <bean id="accountDao" class="com.itheima.dao.impl.AccountDaoImpl">
        <property name="dataSource" ref="dataSource"></property>
    </bean>


    <!-- 配置数据源-->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/eesy"></property>
        <property name="username" value="root"></property>
        <property name="password" value="1234"></property>
    </bean>

    <!-- spring中基于XML的声明式事务控制配置步骤
        1、配置事务管理器
        2、配置事务的通知
                此时我们需要导入事务的约束 tx名称空间和约束，同时也需要aop的
                使用tx:advice标签配置事务通知
                    属性：
                        id：给事务通知起一个唯一标识
                        transaction-manager：给事务通知提供一个事务管理器引用
        3、配置AOP中的通用切入点表达式
        4、建立事务通知和切入点表达式的对应关系
        5、配置事务的属性
               是在事务的通知tx:advice标签的内部

     -->
    <!-- 配置事务管理器 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!-- 配置事务的通知-->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <!-- 配置事务的属性
                isolation：用于指定事务的隔离级别。默认值是DEFAULT，表示使用数据库的默认隔离级别。
                propagation：用于指定事务的传播行为。默认值是REQUIRED，表示一定会有事务，增删改的选择。查询方法可以选择SUPPORTS。
                read-only：用于指定事务是否只读。只有查询方法才能设置为true。默认值是false，表示读写。
                timeout：用于指定事务的超时时间，默认值是-1，表示永不超时。如果指定了数值，以秒为单位。
                rollback-for：用于指定一个异常，当产生该异常时，事务回滚，产生其他异常时，事务不回滚。没有默认值。表示任何异常都回滚。
                no-rollback-for：用于指定一个异常，当产生该异常时，事务不回滚，产生其他异常时事务回滚。没有默认值。表示任何异常都回滚。
        -->
        <tx:attributes>
            <tx:method name="*" propagation="REQUIRED" read-only="false"/>
            <tx:method name="find*" propagation="SUPPORTS" read-only="true"></tx:method>
        </tx:attributes>
    </tx:advice>

    <!-- 配置aop-->
    <aop:config>
        <!-- 配置切入点表达式-->
        <aop:pointcut id="pt1" expression="execution(* com.itheima.service.impl.*.*(..))"></aop:pointcut>
        <!--建立切入点表达式和事务通知的对应关系 -->
        <aop:advisor advice-ref="txAdvice" pointcut-ref="pt1"></aop:advisor>
    </aop:config>
</beans>

5.测试类如下：

/**
 * 使用Junit单元测试：测试我们的配置
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:bean.xml")
public class AccountServiceTest {

    @Autowired
    private  IAccountService as;

    @Test
    public  void testTransfer(){
        as.transfer("aaa","bbb",100f);

    }
}

spring注解和xml的事务配置

1.service层代码修改如下：

/**
 * 账户的业务层实现类
 *
 * 事务控制应该都是在业务层
 */
@Service("accountService")
@Transactional(propagation= Propagation.SUPPORTS,readOnly=true)//只读型事务的配置
public class AccountServiceImpl implements IAccountService{

    @Autowired
    private IAccountDao accountDao;


    @Override
    public Account findAccountById(Integer accountId) {
        return accountDao.findAccountById(accountId);

    }


    //需要的是读写型事务配置
    @Transactional(propagation= Propagation.REQUIRED,readOnly=false)
    @Override
    public void transfer(String sourceName, String targetName, Float money) {
        System.out.println("transfer....");
            //2.1根据名称查询转出账户
            Account source = accountDao.findAccountByName(sourceName);
            //2.2根据名称查询转入账户
            Account target = accountDao.findAccountByName(targetName);
            //2.3转出账户减钱
            source.setMoney(source.getMoney()-money);
            //2.4转入账户加钱
            target.setMoney(target.getMoney()+money);
            //2.5更新转出账户
            accountDao.updateAccount(source);

            int i=1/0;

            //2.6更新转入账户
            accountDao.updateAccount(target);
    }
}

2.spring配置文件修改如下：

<?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"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <!-- 配置spring创建容器时要扫描的包-->
    <context:component-scan base-package="com.itheima"></context:component-scan>

    <!-- 配置JdbcTemplate-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!-- 配置数据源-->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/eesy"></property>
        <property name="username" value="root"></property>
        <property name="password" value="1234"></property>
    </bean>

    <!-- spring中基于注解 的声明式事务控制配置步骤
        1、配置事务管理器
        2、开启spring对注解事务的支持
        3、在需要事务支持的地方使用@Transactional注解
     -->
    <!-- 配置事务管理器 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <!-- 开启spring对注解事务的支持-->
    <tx:annotation-driven transaction-manager="transactionManager"></tx:annotation-driven>
</beans>

其余地方一样。

基于注解的声明式事务控制

1.引入依赖如下；

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>5.0.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.6</version>
    </dependency>

    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.8.7</version>
    </dependency>

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

2.dao 层代码如下：

/**
 * 账户的持久层实现类
 */
@Repository("accountDao")
public class AccountDaoImpl implements IAccountDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @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);
    }

    @Override
    public Account findAccountByName(String accountName) {
        List<Account> accounts = jdbcTemplate.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);
    }

    @Override
    public void updateAccount(Account account) {
        jdbcTemplate.update("update account set name=?,money=? where id=?",account.getName(),account.getMoney(),account.getId());
    }
}

3.service层代码如下：

/**
 * 账户的业务层实现类
 *
 * 事务控制应该都是在业务层
 */
@Service("accountService")
@Transactional(propagation= Propagation.SUPPORTS,readOnly=true)//只读型事务的配置
public class AccountServiceImpl implements IAccountService{

    @Autowired
    private IAccountDao accountDao;


    @Override
    public Account findAccountById(Integer accountId) {
        return accountDao.findAccountById(accountId);

    }


    //需要的是读写型事务配置
    @Transactional(propagation= Propagation.REQUIRED,readOnly=false)
    @Override
    public void transfer(String sourceName, String targetName, Float money) {
        System.out.println("transfer....");
            //2.1根据名称查询转出账户
            Account source = accountDao.findAccountByName(sourceName);
            //2.2根据名称查询转入账户
            Account target = accountDao.findAccountByName(targetName);
            //2.3转出账户减钱
            source.setMoney(source.getMoney()-money);
            //2.4转入账户加钱
            target.setMoney(target.getMoney()+money);
            //2.5更新转出账户
            accountDao.updateAccount(source);

//            int i=1/0;

            //2.6更新转入账户
            accountDao.updateAccount(target);
    }
}

4.数据库连接信息配置如下： jdbcConfig.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/eesy
jdbc.username=root
jdbc.password=1234

/**
 * 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
     * @param dataSource
     * @return
     */
    @Bean(name="jdbcTemplate")
    public JdbcTemplate createJdbcTemplate(DataSource dataSource){
        return new JdbcTemplate(dataSource);
    }

    /**
     * 创建数据源对象
     * @return
     */
    @Bean(name="dataSource")
    public DataSource createDataSource(){
        DriverManagerDataSource ds = new DriverManagerDataSource();
        ds.setDriverClassName(driver);
        ds.setUrl(url);
        ds.setUsername(username);
        ds.setPassword(password);
        return ds;
    }
}

5.事务配置类如下：

/**
 * 和事务相关的配置类
 */
public class TransactionConfig {

    /**
     * 用于创建事务管理器对象
     * @param dataSource
     * @return
     */
    @Bean(name="transactionManager")
    public PlatformTransactionManager createTransactionManager(DataSource dataSource){
        return new DataSourceTransactionManager(dataSource);
    }
}

6.spring配置类（启动类）如下：

/**
 * spring的配置类，相当于bean.xml
 */
@Configuration
@ComponentScan("com.itheima")
@Import({JdbcConfig.class,TransactionConfig.class})
@PropertySource("jdbcConfig.properties")
@EnableTransactionManagement//开启事务支持
public class SpringConfiguration {
}

7.测试类如下：

/**
 * 使用Junit单元测试：测试我们的配置
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes= SpringConfiguration.class)
public class AccountServiceTest {

    @Autowired
    private  IAccountService as;

    @Test
    public  void testTransfer(){
        as.transfer("aaa","bbb",100f);

    }
}