按照字符串的長短進行排序

 使用TreeSet知識對字符串的長短排序

import java.util.Comparator;
import java.util.Iterator;
import java.util.TreeSet;

public class TreeSetTest4
{
	public static void main(String[] args)
	{
		TreeSet tSet = new TreeSet(new ComparatorString());
		tSet.add("abca");
		tSet.add("aaa");
		tSet.add("ddadd");
		tSet.add("bcas");
		Iterator it = tSet.iterator();
		while (it.hasNext())
		{
			System.out.println(it.next());
		}

	}
}

class ComparatorString implements Comparator
{
	public int compare(Object ob1, Object ob2)
	{
		String s1 = (String) ob1;
		String s2 = (String) ob2;
		if (s1.length() > s2.length())
		{
			return 1;
		}

		if (s1.length() == s2.length())
		{
			return s1.compareTo(s2);
		}
		return -1;
	}
}