PriorityQueue

# PriorityQueue

import java.util.PriorityQueue;

import java.util.Queue;

public class MyPrioirityQueue {

public static void main(String[] args) {

Queue<Person> myQueue = new PriorityQueue<>();

myQueue.add(new Person("Adam", 26));

myQueue.add(new Person("Joe", 36));

myQueue.add(new Person("Ada", 24));

// System.out.println(myQueue.peek());

while (myQueue.peek() != null)

{

System.out.print(myQueue.poll() + " ");

}

}

}

# 큐에 담을 객체

public class Person implements Comparable<Person> {

private String name;

private Integer age;

public Person(String name, Integer age) {

super();

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;

}

@Override

public String toString() {

return this.name + " - " + this.age;

}

@Override

public int compareTo(Person otherPerson) {

return -Integer.compare(this.age, otherPerson.getAge());

}

}

# 실행 결과

# compareTo 메쏘드를 중복정의해서 리턴값에 -를 붙여 큰 정수부터 꺼낼때

Joe - 36 Adam - 26 Ada - 24 

# 

compareTo 메쏘드를 중복정의해서 리턴값에 -가 없는 경우 작은 정수부터 꺼낼때

Ada - 24 Adam - 26 Joe - 36