java中比较器Comparator的使用（结合PriorityQueue）

上期我们简单的介绍了下java中的排序接口Comparable的使用，由于Comparable是不够灵活的一种排序接口，它要去修改对象的类的代码。所以，我们今天介绍一款较为灵活的比较器接口Comparator。

首先，还是创建一个实体类Person2:

public class Person2 {
    private int age;
    private String name;
    private int xuehao;

    public Person2() {
    }

    public Person2(int age, String name, int xuehao) {
        this.age = age;
        this.name = name;
        this.xuehao = xuehao;
    }

    public int getXuehao() {
        return xuehao;
    }

    public void setXuehao(int xuehao) {
        this.xuehao = xuehao;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "Person2{" +
                "age=" + age +
                ", name='" + name + '\'' +
                ", xuehao=" + xuehao +
                '}';
    }

}

然后在我们的创作一个测试类Mytest:

public class Mytest {
    public static void main(String[] args) {
        Person2[] person2s = {new Person2(15,"张三",34),
                new Person2(5, "李四",12),
                new Person2(10, "王五",88)};

        //创建比较器对象cp
        Comparator<Person2> cp = new Comparator<Person2>() {
            @Override//重写compare方法，使按照xuehao升序
            //o2.getXuehao()-o1.getXuehao()：按照xuehao降序
            public int compare(Person