Map

package com.day13;

public class Student {
    private String name;
    private String sex;

    public Student(){}
    public Student(String name,String sex){
        this.name = name;
        this.sex = sex;
    }
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }
}

package com.day13;
import java.util.Map;
import java.util.HashMap;
import java.util.Scanner;
public class Test {
    public static void main(String[] args) {
        Map students = new HashMap();
        Student s1 = new Student("张一","男");
        Student s2 = new Student("张二","女");
        Student s3 = new Student("张三","男");
        //键，值对：学员的英文名字，学号
        students.put("jacak1",s1);
        students.put("jacak2",s2);
        students.put("jacak3",s3);

        //根据特定Key获取相应value
        Scanner input = new Scanner(System.in);
        System.out.println("请输入你要寻找的学生英文名：");
        String key = input.next();
        if(students.containsKey(key)){
            Student stu = (Student)students.get(key);
            System.out.println("您要找的学员是："+stu.getName()+"-"+stu.getSex());
        }else{
            System.out.println("对不起");
        }
    }
}