4.5.5PriorityBlockingQueue简介和基本使用demo

支持优先级的无界阻塞队列：默认情况下元素采取自然顺序升序排列，可以以自定义compareTo()方法来指定元素的排序规则。

demo：通过年龄比较大小，实现Comparable

实体

public class Person implements Comparable {
    private String name;
    private Integer age;

    public Person(String name, Integer age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

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

    public Integer getAge() {
        return age;
    }

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

    //实现比较方法
    @Override
    public int compareTo(Object o) {
        Person p = (Person) o;
        return this.age - p.getAge();
    }

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

测试

public class Test {
    public static void main(String[] args) {
        PriorityBlockingQueue queue = new PriorityBlockingQueue();
        queue.add(new Person("1",45));
        queue.add(new Person("2",2));
        queue.add(new Person("3",4));
        queue.add(new Person("4",3));
        System.out.println(queue);
    }
}

结果：通过年龄排序

[Person{name='2', age=2}, Person{name='4', age=3}, Person{name='3', age=4}, Person{name='1', age=45}]