MyBatis输入映射parameterType

案例：

1.User.java以及SqlMapConfig.xml参考MyBatis实现增删改查

2.UserCustom.java继承User.java

package com.test.entity;
/**
 * 
 * @author Mr
 * 属于User的扩展类
 */
public class UserCustom extends User {
    //可以添加一些属性
}

3.UserQueryVo.java类

package com.test.entity;
/**
 * 这个是包装类 ，后面跟控制器有关系
 * @author Mr
 *
 */
public class UserQueryVo {
    //用户的查询条件
    private User user;
    //附加的查询条件
    private UserCustom userCustom;

    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }

    public UserCustom getUserCustom() {
        return userCustom;
    }

    public void setUserCustom(UserCustom userCustom) {
        this.userCustom = userCustom;
    }
    
}

4.UserMapper.java

package com.test.dao;

import java.util.List;

import com.test.entity.User;
import com.test.entity.UserCustom;
import com.test.entity.UserQueryVo;
/**
 * 
 * @author Mr
 * Mapper接口代理模式开发命名一定是：实体类名+Mapper
 * 
 * 使用mapper开发步骤：
 *     1.编写接口和mapper.xml要遵循4个指标
 *     2.SqlMapConfig.xml中加载UserMapper.xml
 */
public interface UserMapper {
    //根据用户id查询用户
    public User findUserById(int id);
    //添加用户
    public void addUser(User user);
    //这个方法对应的是包装类型的statement
    public List<UserCustom> findUserList(UserQueryVo userQueryVo);
}

5.UserMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!-- namespace命名空间是UserMapper接口的全类名-->
<mapper namespace="com.test.dao.UserMapper"> 
 <!-- 查询  注意了 type后面是包装类-->
 <select id="findUserList" parameterType="com.test.entity.UserQueryVo" resultType="com.test.entity.UserCustom">
     select * from userss WHERE sex=#{userCustom.sex} AND username LIKE '%${userCustom.username}%'
 </select>
 
 
 </mapper>

6.测试类

package com.test.demo;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import com.test.dao.UserMapper;
import com.test.entity.UserCustom;
import com.test.entity.UserQueryVo;

/**
 * 测试包装类型的pojo
 * @author Mr
 *
 */
public class Test4 {

    public static void main(String[] args) {
        try {
            //mybatis核心文件
            String resource = "SqlMapConfig.xml";
            //读取配置文件
            InputStream config = Resources.getResourceAsStream(resource);
            //获取工厂
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(config);
            //获取数据库操作对象
            SqlSession sqlSession = sqlSessionFactory.openSession();
            //获取实现类对象
            UserMapper um = sqlSession.getMapper(UserMapper.class);
            
            UserQueryVo userQueryVo = new UserQueryVo();
            //参数是userCustom的
            UserCustom userCustom = new UserCustom();
            userCustom.setSex("1");
            userCustom.setUsername("张");
            //他们俩存在关系
            userQueryVo.setUserCustom(userCustom);
            
            List<UserCustom> list = um.findUserList(userQueryVo);
            for (UserCustom uu : list) {
                System.out.println(uu);
            }
            
            
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        

    }

}