spring3 jdbctemplate 注解实例

本文章摘编、转载需要注明来源 http://blog.csdn.net/shadowsick/article/details/8888187[/code] 
网上这spring jdbctemplate的例子多如牛毛,我下面也继续再造一次轮子

第一步,先引入需要的包,这里不作详细说明

第二步,配置注解扫描,txManager是事务管理提供datasource就可以了

<aop:aspectj-autoproxy />

<!-- transaction manager, use JtaTransactionManager for global tx -->
<bean id="txManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dynamicDataSource" />
</bean>

<!--
enable component scanning (beware that this does not enable mapper
scanning!)
-->
<context:component-scan base-package="com.shadow" />

<!-- enable autowire -->
<context:annotation-config />

<!-- enable transaction demarcation with annotations -->
<tx:annotation-driven transaction-manager="txManager" />


第三步,配置jdbctemplate的实例,同样提供一个datasource就可以了

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


第四步,写个BaseDao方便下面的dao层调用,由于时间转换经常用到,这里只写了个通用的时间转换

/**
*
* @author shadow
* @email 124010356@qq.com
* @create 2012.04.28
*
* @param <T>
*/
public abstract class AbstractBaseDao<T> implements DateFormatEntry {

// SPRING JDBC模板接口
private JdbcTemplate jdbcTemplate;

public JdbcTemplate getJdbcTemplate() {
return jdbcTemplate;
}

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

/**
* 获取日期
*
* @param timestamp
* @return Date
*/
public Date getDate(Timestamp timestamp) {
return toDate(timestamp, null);
}

/**
* 获取日期
*
* @param timestamp
* @param format
* @return Date
*/
public Date getDate(Timestamp timestamp, String format) {
return toDate(timestamp, format);
}

/**
* Timestamp按格式转换成Date
*
* @param timestamp
* @param format
* @return Date
*/
public Date toDate(Timestamp timestamp, String format) {
Date date = null;
if (null == format || "".equals(format))
format = DEFAULT_FORMAT;
SimpleDateFormat sdf = new SimpleDateFormat(format);
try {
date = sdf.parse(sdf.format(timestamp));
} catch (ParseException e) {
e.printStackTrace();
}
return date;
}

}


第五步,写个UserDao接口跟实现类

public interface UserDao {

public List<User> queryByUserName(String username);

public int checkUser(String username);

public List<User> queryForAll();

}


这里使用@Component("userDao"),相当于在xml配置里做一个<bean id="userDao" class="xxxxxx.UserDaoImpl"/>,然后我们在service调用就直接Resource("userDao")就能自动匹配这个实现类了

@Component("userDao")
public class UserDaoImpl extends AbstractBaseDao<User> implements UserDao {

public int checkUser(String username) {
// TODO Auto-generated method stub
return 0;
}

@SuppressWarnings("unchecked")
public List<User> queryByUserName(String username) {
String sql = "select t1.* from t_user t1 where t1.username = ?";
List<User> list = this.getJdbcTemplate().query(sql,
new Object[] { username }, new UserMapper());
return list;
}

public List<User> queryForAll() {
SqlRowSet rowSet = getJdbcTemplate().queryForRowSet(null);
while (rowSet.next()) {
}
return null;
}

@SuppressWarnings("unchecked")
private class UserMapper implements RowMapper {
public Object mapRow(ResultSet rs, int i) throws SQLException {
User vo = new User();
vo.setId(rs.getInt("id"));
vo.setUsername(rs.getString("username"));
vo.setPassword(rs.getString("password"));
vo.setName(rs.getString("name"));
return vo;
}
}

}


第六步,写service层调用dao的方法

public interface UserService {

/**
* 更新登录信息
*
* @param user
*/
public void LoginForUpdate(User user);

/**
* 安全退出功能
*
* @return String
*/
public String logout();

/**
* 检测用户是否存在
*
* @param username
* @return Boolean
*/
public boolean checkUser(String username);

/**
* 通过用户名获取账号
*
* @param username
* @return List<User>
*/
public List<User> findByUserName(String username);


这里使用了的@Resource没有带参数就是默认使用接口类名首字母小写(例如接口是UserDao,默认匹配是userDao),@Transactional是事务的注解,可加各种参数设置,

具体请看帮助文档

@Transactional
@Component("userService")
public class UserServiceImpl implements UserService {

@Resource
private UserDao userDao;

public void LoginForUpdate(User user) {
// TODO Auto-generated method stub
}

public boolean checkUser(String username) {
// TODO Auto-generated method stub
return false;
}

public List<User> findByUserName(String username) {
return this.userDao.queryByUserName(username);
}

public String logout() {
// TODO Auto-generated method stub
return null;
}

}


第七步,写junit测试

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:application.xml")
public class Junit {

@Resource
private UserService userService;

@Test
public void test() {
for (int i = 0; i < 10; i++) {
List<User> users = userService.findByUserName("3213231");
System.out.println("当前用户数:" + users.size());
}
}

}


最后右键run as junit就ok了

附言,其实spring jdbctemplate是很灵活的,性能也很不错,你能使用queryForXX一类的方法返回map,也能返回原始ResultSet,当然也能使用回调接口映射成对象,我的例子里就是演示了如何把结果集映射成实体对象