java_泛型 TreeSet 判断hashcode/length(升序排列)

package ming;



import java.util.ArrayList;

import java.util.Collection;

import java.util.Comparator;

import java.util.List;

import java.util.TreeSet;

/*

 * 按照hashcode或者length排列

 * 以升序排列

 * 实现TreeSet

 * */



class A11 implements Comparator<Object> {



	@Override

	//Object为String父类，符合要求

	public int compare(Object fst, Object snd) {

		return hashCode() > snd.hashCode() ? 1

				: hashCode() < snd.hashCode() ? -1 : 0;

	}



}



public class GenericMethodTest {

	public static void main(String[] args) {

		TreeSet<String> ts1 = new TreeSet<String>(new A11());



		ts1.add("hello");

		ts1.add("wa");



		TreeSet<String> ts2 = new TreeSet<String>(new Comparator<String>() {

			public int compare(String fst, String snd) {

				return fst.length() > snd.length() ? -1

						: fst.length() < snd.length() ? 1 : 0;

			}

		});

		ts2.add("hello");

		ts2.add("wa");

		ts2.add("one");

		System.out.println(ts1);

		System.out.println(ts2);

	}

}