public class ComparatorsByName implements Comparator {
	public int compare(Object o1,Object o2) {
		return 1;
	}
}

16-13，TreeSet练习

需求：按照字符串的长度排序。

public class TreeSetTest {
	public static void main(String[] args) {
		TreeSet ts = new TreeSet(new ComparatorsByLength());
		ts.add("aaaaaa");
		ts.add("zz");
		ts.add("nabq");
		ts.add("cba");
		ts.add("abc");
		Iterator it = ts.iterator();
		while(it.hasNext()) {
			System.out.println(it.next());
		}
	}
}

//比较器
public class ComparatorsByLength implements Comparator {
	public int compare(Object o1,Object o2) {
		String s1 = (String)o1;
		String s2 = (String)o2;
		int temp = s1.length() - s2.length();
		return temp == 0   s1.compareTo(s2) : temp;
	}
}