标签:信息 Opens splay zab == import mapper index ec2
例子:根据多个id查询用户
User.xml:
1 <!--多个id查询 通过queryvo --> 2 <select id="selectUserByIds" parameterType="QueryVo" 3 resultType="User"> 4 <include refid="selector" /> 5 <where> 6 id in 7 <foreach collection="idlist" item="id" separator="," open="(" 8 close=")"> 9 #{id} 10 </foreach> 11 </where> 12 </select>
UserMapper.java:
1 package com.me.mybatis.mapper; 2 3 import java.util.List; 4 5 import com.me.mybatis.pojo.QueryVo; 6 import com.me.mybatis.pojo.User; 7 8 public interface UserMapper { 9 //遵循四个原则 10 //1.接口方法名==user.xml文件中的id名 11 //2.返回值类型与mapper.xml文件中的返回值类型要一致 12 //3.方法的入参类型与mapper.xml中入参的类型一致 13 //4.mapper.xml文件的namespace与接口绑定在一起 14 public User findUserById(Integer id); 15 public List<User> findUserByQueryVo(QueryVo vo); 16 public Integer countUsers(); 17 public List<User> selectUserBySexAndUserName(User user); 18 //根据多个id查询用户信息 19 public List<User> selectUserByIds(Integer[] ids); 20 public List<User> selectUserByIds(List<Integer> ids); 21 public List<User> selectUserByIds(QueryVo vo); 22 23 }
QueryVo.java:
1 package com.me.mybatis.pojo; 2 3 import java.io.Serializable; 4 import java.util.List; 5 6 public class QueryVo implements Serializable { 7 8 /** 9 * 10 */ 11 private static final long serialVersionUID = 1L; 12 private User user; 13 private List<Integer> idlist; 14 private Integer[] ids; 15 public List<Integer> getIdlist() { 16 return idlist; 17 } 18 public void setIdlist(List<Integer> idlist) { 19 this.idlist = idlist; 20 } 21 public Integer[] getIds() { 22 return ids; 23 } 24 public void setIds(Integer[] ids) { 25 this.ids = ids; 26 } 27 public User getUser() { 28 return user; 29 } 30 public void setUser(User user) { 31 this.user = user; 32 } 33 }
测试类:
1 @Test 2 void testselectUserByIds() throws Exception { 3 // 加载核心配置文件 4 String resource = "SqlMapConfig.xml"; 5 InputStream resourceAsStream = Resources.getResourceAsStream(resource); 6 // 创建sqlsessionFactory 7 SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream); 8 // 创建sqlsession 9 SqlSession openSession = sqlSessionFactory.openSession(); 10 //sqlsession生成一个实现类 11 UserMapper mapper = openSession.getMapper(UserMapper.class); 12 //利用接口调方法 13 List<Integer> ids=new ArrayList<Integer>(); 14 ids.add(16); 15 ids.add(22); 16 ids.add(24); 17 QueryVo vo=new QueryVo(); 18 vo.setIdlist(ids); 19 List<User> users = mapper.selectUserByIds(vo); 20 for (User user1 : users) { 21 22 System.out.println(user1); 23 } 24 25 }
结果:
注意:
index:为数组的下标。
item:为数组每个元素的名称,名称随意定义
open:循环开始
close:循环结束
separator:中间分隔输出
别的都一样但是应该注意:、
标签:信息 Opens splay zab == import mapper index ec2
原文地址:https://www.cnblogs.com/tkg1314/p/12285329.html