Spring中JdbcTemplate使用RowMapper

1 1 package com.cxl.demo.dao;  
2 2   
3 3 import java.sql.ResultSet;  
4 4 import java.sql.SQLException;  
5 5 import java.util.List;  
6 6 import org.springframework.jdbc.core.JdbcTemplate;  
7 7 import org.springframework.jdbc.core.RowMapper;  
8 8 import com.cxl.demo.entity.User;  
9 9 public class UserDaoImpl {  
1010     private JdbcTemplate jdbcTemplate;  
1111   
1212     public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {  
1313         this.jdbcTemplate = jdbcTemplate;  
1414     }  
1515   
1616     public List<User> getUserByName(String username) {  
1717         String sql = "select * from t_user where username = ?";  
1818         Object[] params = new Object[] { username };  
1919         List<User> users = null;  
2020         /** 
2121          * 使用接口实现类 
2222          */  
2323         users = jdbcTemplate.query(sql, params, new UserRowMapper());  
2424         /** 
2525          * 使用匿名内部类 
2626          * 如果UserRowMapper类只使用一次，单独为其创建一个类多余，可以使用匿名类 
2727          * 省略了书写一个实现类 
2828          */  
2929         users = jdbcTemplate.query(sql, params,  
3030                 new RowMapper<User>() {  
3131                     @Override  
3232                     public User mapRow(ResultSet rs, int rowNum) throws SQLException {  
3333                         User user = new User();  
3434                         user.setId(rs.getInt("id"));  
3535                         user.setUsername(rs.getString("username"));  
3636                         user.setPassword(rs.getString("password"));  
3737                         return user;  
3838                     }  
3939                 });  
4040         return (users != null && users.size() > 0) ? users : null;  
4141     }  
4242       
4343     public class UserRowMapper implements RowMapper<User> {  
4444   
4545         @Override  
4646         public User mapRow(ResultSet rs, int rowNum) throws SQLException {  
4747             User user = new User();  
4848             user.setId(rs.getInt("id"));  
4949             user.setUsername(rs.getString("username"));  
5050             user.setPassword(rs.getString("password"));  
5151             return user;  
5252         }  
5353           
5454     }  
5555 }