在HashMap中查找

请将查找目标的过程定义为类方法,查找时直接调用类方法

import java.util.HashMap;

public class HashMapExample
{
public static void main(String[] args) throws Exception
{
HashMap<String , student> students = new HashMap<String, student>();

student s1 = new student("12345-12","AAA");
student s2 = new student("98765-00","BBB");
student s3 = new student("55667-99","CCC");

students.put(s1.getIdNo(),s1);
students.put(s2.getIdNo(),s2);
students.put(s3.getIdNo(),s3);

String id = "98765-00";
System.out.println("Let's try to retrive a Student with ID = "+ id);
student x = students.get(id);
if (x!=null)
{
System.out.println("Found! Name = "+ x.getName());
}
else {
System.out.println("Invalid ID: "+ id);}

System.out.println();