- 方法
queryForList(sql, args)
sql 要执行的sql语句,args 动态sql时要传入的参数
queryForMap(sql, args)
sql 要执行的sql语句,args 动态sql时要传入的参数
queryForObject(sql, args, requiredType)
sql 要执行的sql语句,args 动态sql时要传入的参数, requiredType 返回值类型(基本数据类型的封装类,如Integer、String),如果要自定义返回值类型,则为new BeanPropertyRowMapper(User.class) (User为自定义类)
- example
package com.example.test;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
@Controller
public class Test {
@Autowired
private JdbcTemplate jdbcTemplate;
/**
* queryForList 和 queryForMap 的例子
* @return
*/
@RequestMapping("/getList")
public String getList(){
// queryForList 例子, 不传参数的普通sql
String sql = "select * from user ";
List<Map<String, Object>> list = jdbcTemplate.queryForList(sql);
if(null != list) {
System.out.println(list.toString());
}
// queryForList 例子, 动态出入参数
sql = "select * from user where id > ? " ;
List<Map<String, Object>> list2 = jdbcTemplate.queryForList(sql,
new Object[] {3});
if(null != list2) {
System.out.println(list2.toString());
}
// queryForMap 例子
sql = "select * from user where id = ? " ;
Map<String,Object> map = jdbcTemplate.queryForMap(sql,new Object[] {3});
if(null != map) {
System.out.println(map.toString());
}
return "index";
}
/**
* queryForObject 的例子
* @return
*/
@RequestMapping("/getUser")
public String getUser(){
String sql = "select id,username,pwd,tel from user where id = 2";
User user = (User) jdbcTemplate.queryForObject(sql, null,
new BeanPropertyRowMapper(User.class)) ;
if(null != user) {
System.out.println(user.toString());
}
return "index";
}
}
/*** 后面遇到问题时再更新 ***/