mycollection.java

JAVA SE6 全方位学习 朱仲杰 编著 机械工业出版社出版

package java2.F;

import java.util.*;

public class MyCollection implements Iterable<String>
{
	private StringBuilder sb = new StringBuilder();
	
	public void add(String str)
	{
		if (sb.length() == 0)
			sb.append(str);
		else
			sb.append(",").append(str);
	}
	
	public Iterator<String> iterator()
	{
		return new MyIterator(sb.toString());
	}
}

class MyIterator implements Iterator<String>
{
	StringTokenizer st = null;
	public MyIterator(String data)
	{
		st = new StringTokenizer(data, ",");
	}
	
	public boolean hasNext()
	{
		return st.hasMoreTokens();
	}
	
	public String next()
	{
		return st.nextToken();
	}
	
	public void remove()
	{
		throw new UnsupportedOperationException();
	}
}