Arrays.sort 与 Collections.sort

 

代码如下：

 

package com.wangzhu.arrays;



import java.util.Arrays;

import java.util.Collections;



public class ArraysDemo {



    /**

     * @param args

     */

    public static void main(String[] args) {

        Dog[] dogs = new Dog[] { new Dog(5), new Dog(2), new Dog(19),

                new Dog(21), new Dog(12), new Dog(1) };

        printObject(dogs);

        // Arrays.sort(dogs);

        Collections.sort(Arrays.asList(dogs));

        printObject(dogs);



        Cat[] cats = new Cat[] { new Cat(10), new Cat(0), new Cat(4),

                new Cat(5), new Cat(3) };

        printObject(cats);

        // Arrays.sort(cats);

        Collections.sort(Arrays.asList(cats));

        printObject(cats);

    }



    public static void printObject(Animal[] animals) {

        for (Animal animal : animals) {

            System.out.print("size = " + animal.getClass().getSimpleName()

                    + animal.size + " ");

        }

        System.out.println();

    }



}



class Animal implements Comparable<Animal> {

    int size;



    @Override

    public int compareTo(Animal animal) {

        return this.size - animal.size;

    }

}



class Dog extends Animal {

    public Dog(int size) {

        this.size = size;

    }

}



class Cat extends Animal {

    public Cat(int size) {

        this.size = size;

    }

}