TreeSet的使用：获得一组数中的不同数（排序）

import java.io.BufferedInputStream;
import java.util.Iterator;
import java.util.Scanner;
import java.util.Set;
import java.util.TreeSet;

public class Main {
	public static void main(String[] args) {
		Scanner cin = new Scanner(new BufferedInputStream(System.in));
		Set<Number> numberSet = new TreeSet<Number>();
		int[] numberArrays = null;
		int nalength = -1;
		Number num = null;
		while (cin.hasNext()) {
			System.out.print("请输入数组的大小：");
			nalength = cin.nextInt();
			System.out.print("\n请输入数组中的元素以空格隔开：");
			numberArrays = new int[nalength];
			for (int i = 0; i < nalength; i++) {
				numberArrays[i] = cin.nextInt();
				num = new Number(numberArrays[i]);
				numberSet.add(num);
			}
			Iterator<Number> iter = numberSet.iterator();
			System.out.print("\n数组中的不同的元素，如下所示：\n");
			while (iter.hasNext()) {
				System.out.print(iter.next().number);
				if (iter.hasNext()) {
					System.out.print(" ");
				}
			}
			System.out.println();
		}
	}
}

class Number implements Comparable<Number> {
	int number;

	Number(int number) {
		this.number = number;
	}

	@Override
	public int compareTo(Number num) {
		int res = this.number - num.number;
		if (res > 0) {
			return 1;
		} else if (res < 0) {
			return -1;
		}
		return 0;
	}
}