package ine.collection;

import java.util.HashMap;

import java.util.Map;

import java.util.Scanner;

import java.util.Set;

public class MapTest {

public Map<String,Student>students;

public MapTest(){

this.students=new HashMap<String,Student>();

}

  public void testPut(){

Scanner consol=new Scanner(System.in);

 for(int i=0;i<3;i++){

 System.out.println("请输入学生ID：");

 String ID=consol.next();

 Student st=students.get(ID);

 if (st==null){

 System.out.println("请输入学生姓名：");

 String name=consol.next();

 Student newStudent=new Student(ID,name);

 //通过调用Studet的put方法，添加ID-学生的映射关系

 students.put(ID, newStudent);

 System.out.println("成功添加："+students.get(ID).name);

 }else{

 System.out.println("该学生ID已被占用！");

 continue;

 }

 }

  }

public void testKeySet(){

Set<String>keySet=students.keySet();

System.out.println("总共有"+students.size()+"个同学");

for (String stuID : keySet) {

Student st=students.get(stuID);

if(st!=null){

System.out.println("学生："+st.name);

}

}

}

public static void main(String[] args) {

// TODO Auto-generated method stub

MapTest temp=new MapTest();

temp.testPut();

temp.testKeySet();

}

}