hashmapdemo.java

这是清华大学编写的JAVA教材中所有题目的源代码！

import java.util.*;

class HashMapDemo
{
	public static void main(String[] args)
	{
		Hashtable ht=new Hashtable();
		
		ht.put("one",new Integer(1));
		ht.put("two",new Integer(2));
		ht.put("three",new Integer(3));
		ht.put("four",new Integer(4));
		ht.put("five",new Integer(5));
		System.out.println(ht);
		
		Enumeration e=ht.elements();
		while(e.hasMoreElements())
			System.out.println(e.nextElement());
		System.out.println();


		HashSet hs=new HashSet();
		
		hs.add(new Integer(1));
		hs.add(new Integer(2));
		hs.add(new Integer(3));
		hs.add(new Integer(4));
		hs.add(new Integer(5));
		System.out.println(hs);
		
		Iterator it=hs.iterator();
		while(it.hasNext())
			System.out.println(it.next());
		System.out.println();
		
		
		HashMap hm=new HashMap();
		
		hm.put("one",new Integer(1));
		hm.put("two",new Integer(2));
		hm.put("three",new Integer(3));
		hm.put("four",new Integer(4));
		hm.put("five",new Integer(5));
		System.out.println(hm);
		
		Collection c=hm.values();
		it=c.iterator();
		while(it.hasNext())
			System.out.println(it.next());
		System.out.println();
	}
}