学步园

本文章摘编、转载需要注明来源 http://blog.csdn.net/shadowsick/article/details/8888187

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