@Param

package com.flying.entity;

public class Student {
    private Integer id;
    private String name;
    private Integer age;
    private String major;
    private Double score;

    public Integer getId() { return id; }
    public void setId(Integer id) { this.id = id; }
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public Integer getAge() { return age; }
    public void setAge(Integer age) { this.age = age; }
    public String getMajor() { return major; }
    public void setMajor(String major) { this.major = major; }
    public Double getScore() { return score; }
    public void setScore(Double score) { this.score = score; }

    @Override
    public String toString() {
        return "Student{id=" + id + ", name='" + name + "', age=" + age +
               ", major='" + major + "', score=" + score + "}";
    }
}

package com.flying.mapper;

import com.flying.entity.Student;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import java.util.List;
import java.util.Map;

public interface StudentMapper {

    /**
     * 根据名称和年龄范围查询学生
     * 多参数必须加 @Param，否则 JDK 8 之前无法识别参数名
     */
    @Select("SELECT id, name, age, major, score FROM student WHERE name LIKE CONCAT('%', #{name}, '%') AND age BETWEEN #{minAge} AND #{maxAge}")
    List<Student> selectByNameAndAgeRange(@Param("name") String name,
                                          @Param("minAge") Integer minAge,
                                          @Param("maxAge") Integer maxAge);

    /**
     * 使用 Map 作为参数，@Param 指定 Map 在 SQL 中的前缀
     */
    @Select("SELECT id, name, age, major, score FROM student WHERE major = #{params.major} AND score >= #{params.minScore}")
    List<Student> selectByMap(@Param("params") Map<String, Object> params);

    /**
     * 根据 ID 列表批量查询
     */
    @Select("<script>SELECT id, name, age, major, score FROM student WHERE id IN " +
            "<foreach collection='ids' item='id' open='(' separator=',' close=')'>#{id}</foreach></script>")
    List<Student> selectByIds(@Param("ids") List<Integer> ids);
}

package com.flying.test;

import com.flying.entity.Student;
import com.flying.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.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class ParamTest {
    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);

        // 1. 多参数查询：名称包含"小"，年龄在 20 到 22 之间
        System.out.println("=== 多参数查询 ===");
        List<Student> list1 = mapper.selectByNameAndAgeRange("小", 20, 22);
        list1.forEach(System.out::println);

        // 2. Map 参数查询：专业为"计算机科学"，分数 >= 90
        System.out.println("\n=== Map 参数查询 ===");
        Map<String, Object> params = new HashMap<>();
        params.put("major", "计算机科学");
        params.put("minScore", 90.0);
        List<Student> list2 = mapper.selectByMap(params);
        list2.forEach(System.out::println);

        // 3. 集合参数查询：查询 ID 为 1, 3, 5 的学生
        System.out.println("\n=== 集合参数查询 ===");
        List<Integer> ids = Arrays.asList(1, 3, 5);
        List<Student> list3 = mapper.selectByIds(ids);
        list3.forEach(System.out::println);

        session.close();
    }
}