// 接口：聲明轉(zhuǎn)賬方法
public interface AccountService {
    void pay(String out, String in, double money); // 付款人、收款人、金額
}

// 實(shí)現(xiàn)類：調(diào)用Dao完成轉(zhuǎn)賬
public class AccountServiceImpl implements AccountService {
    private AccountDao accountDao; // 注入Dao層對象

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

    @Override
    public void pay(String out, String in, double money) {
        accountDao.outMoney(out, money); // 付款方扣款
        accountDao.inMoney(in, money); // 收款方加款
    }
}

// 接口：定義數(shù)據(jù)庫操作
public interface AccountDao {
    void outMoney(String out, double money); // 扣款
    void inMoney(String in, double money); // 加款
}

// 實(shí)現(xiàn)類：使用JdbcTemplate操作數(shù)據(jù)庫
public class AccountDaoImpl implements AccountDao {
    private JdbcTemplate jdbcTemplate; // 注入JdbcTemplate

    public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    @Override
    public void outMoney(String out, double money) {
        jdbcTemplate.update("update account set money=money-? where name=?", money, out);
    }

    @Override
    public void inMoney(String in, double money) {
        jdbcTemplate.update("update account set money=money+? where name=?", money, in);
    }
}

<beans ...>
    <!-- 加載數(shù)據(jù)庫配置 -->
    <context:property-placeholder location="classpath:jdbc.properties"/>
    
    <!-- 配置Druid連接池 -->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${jdbc.driverClassName}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>
    
    <!-- 配置JdbcTemplate -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"/>
    </bean>
    
    <!-- 配置Service和Dao，注入依賴 -->
    <bean id="accountService" class="com.qcbyjy.demo2.AccountServiceImpl">
        <property name="accountDao" ref="accountDao"/>
    </bean>
    
    <bean id="accountDao" class="com.qcbyjy.demo2.AccountDaoImpl">
        <property name="jdbcTemplate" ref="jdbcTemplate"/>
    </bean>
</beans>

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext_dao1.xml")
public class Demo2 {
    @Autowired
    private AccountService accountService;

    @Test
    public void testPay() {
        accountService.pay("熊大", "熊二", 100); // 模擬熊大給熊二轉(zhuǎn)賬100元
    }
}

public class AccountDaoImpl extends JdbcDaoSupport implements AccountDao {
    @Override
    public void outMoney(String out, double money) {
        // 通過getJdbcTemplate()獲取模板對象
        this.getJdbcTemplate().update("update account set money=money-? where name=?", money, out);
    }

    @Override
    public void inMoney(String in, double money) {
        this.getJdbcTemplate().update("update account set money=money+? where name=?", money, in);
    }
}

<bean id="accountDao" class="com.qcbyjy.demo3.AccountDaoImpl">
    <property name="dataSource" ref="dataSource"/> <!-- 注入數(shù)據(jù)源 -->
</bean>

<beans ...>
    <!-- 配置事務(wù)管理器 -->
    <bean id="transactionManager" 
          class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/> <!-- 綁定數(shù)據(jù)源 -->
    </bean>

    <!-- 啟用注解事務(wù) -->
    <tx:annotation-driven transaction-manager="transactionManager"/>
</beans>

@Service
public class AccountServiceImpl implements AccountService {
    @Autowired
    private AccountDao accountDao;

    // 聲明該方法需要事務(wù)支持
    @Transactional
    @Override
    public void pay(String out, String in, double money) {
        accountDao.outMoney(out, money); // 若此處拋出異常，兩個操作都會回滾
        accountDao.inMoney(in, money);
    }
}