resultMap

package com.flywing.entity;

public class Student {
    private Integer stuId;
    private String stuName;
    private Integer stuAge;
    private String stuMajor;
    private Double stuScore;

    // Getter与Setter
    public Integer getStuId() { return stuId; }
    public void setStuId(Integer stuId) { this.stuId = stuId; }
    public String getStuName() { return stuName; }
    public void setStuName(String stuName) { this.stuName = stuName; }
    public Integer getStuAge() { return stuAge; }
    public void setStuAge(Integer stuAge) { this.stuAge = stuAge; }
    public String getStuMajor() { return stuMajor; }
    public void setStuMajor(String stuMajor) { this.stuMajor = stuMajor; }
    public Double getStuScore() { return stuScore; }
    public void setStuScore(Double stuScore) { this.stuScore = stuScore; }
}

package com.flywing.mapper;

import com.flywing.entity.Student;
import java.util.List;

public interface StudentMapper {
    // 使用基础resultMap查询
    Student findById(Integer id);

    // 使用继承的resultMap查询
    Student findFullById(Integer id);

    // 查询列表
    List<Student> findAll();
}

package com.flywing.test;

import com.flywing.entity.Student;
import com.flywing.mapper.StudentMapper;
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 java.io.InputStream;
import java.util.List;

public class ResultMapTest {
    public static void main(String[] args) throws Exception {
        InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
        SqlSession session = factory.openSession();
        StudentMapper mapper = session.getMapper(StudentMapper.class);

        // 场景一：基础resultMap
        Student s1 = mapper.findById(1);
        System.out.println("基础resultMap查询：");
        System.out.println("  ID=" + s1.getStuId() + "，姓名=" + s1.getStuName() + "，年龄=" + s1.getStuAge());

        // 场景二：扩展resultMap
        Student s2 = mapper.findFullById(2);
        System.out.println("扩展resultMap查询：");
        System.out.println("  ID=" + s2.getStuId() + "，姓名=" + s2.getStuName()
                + "，专业=" + s2.getStuMajor() + "，分数=" + s2.getStuScore());

        // 场景三：列表查询
        List<Student> list = mapper.findAll();
        System.out.println("列表查询结果：");
        for (Student s : list) {
            System.out.println("  " + s.getStuId() + " | " + s.getStuName()
                    + " | " + s.getStuMajor() + " | " + s.getStuScore());
        }

        session.close();
    }
}