Iterator, Enumeration을 이용.. 키값 추출해 HashMap 사용

import java.util.Enumeration;

import java.util.Hashtable;

public class StudentHashtableTest {

public static void main(String[] args) {

Hashtable table = new Hashtable();

table.put("1", new Student("Jee", 1, "Seoul"));

table.clear();

table.put("2", new Student("Gong", 2, "Seoul")); // 1

table.put("3", new Student("Song", 3, "Seoul")); // 2

table.put("4", new Student("Lee", 4, "Koyang")); // 3

table.put("4", new Student("Lee", 4, "Koyang")); // 3과 중복

System.out.println(table.size());

System.out.println(table.containsKey("4"));

table.remove("3");

Student stu = (Student)table.get("2");

System.out.println(stu.getId() + "   " + stu.getName() + "   " + stu.getAddr());

// 모든 elements 출력하기

// Set set = table.keySet(); // Map을 참고

Enumeration enums = table.keys();

while(enums.hasMoreElements()){

String key = (String)enums.nextElement(); // 핵심

System.out.println("key : " + key);

Student stus = (Student)table.get(key);

System.out.println(stus.getId() + "   " + stus.getName() + "   " + stus.getAddr());

}

}

}