Question

JAVA. Create an application that uses a "PriorityQueue" to perform the following

• Uses the constructor that receives a "Comparator" object as an argument
• Stores 5 "Time1" objects using the "Time1" class shown in Fig. 8.1 on page 331. The class must be modified to implement the "Comparator" interface
• Displays the "Universal Time" in priority order

Note: To determine the ordering when implementing the "Comparator" interface, convert the time into seconds (i.e., hours * 3600 + minutes * 60 + seconds), smaller values infer higher priority)

// Fig 8.1: Time1.java
public class Time1 {
   private int hour;
   private int minute;
   private int second;
  
   public void setTime(int hour, int minute, int second) {
       if (hour < 0 || hour >= 24 || minute < 0 || minute >= 60 ||
           second < 0 || second >= 60 {
           throw new IllegalArgumentException(
               "hour, minute and/or second was out of range");
       }
      
       this.hour = hour;
       this.minute = minute;
       this.second = second;
   }
  
   public String to UniversalString() {
       return String.format("%02d:%2d:%02d", hour, minute, second);
   }
  
   public String toString() {
       return String.format("%d:%02d:%02d %s",
       ((hour == 0 || hour == 12) ? 12 : hour % 12),
       minute, second, (hour < 12 ? "AM" : "PM"));
   }
}

Answer 1

ЗУ <terminated> TimeObjDemo [Ja 40 10:10:10 AM 41 class Time1Queue 42 10:30:10 AM 10:30:30 AM PriorityQueue<Time1> dataQueue; 43 1:10:10 PM 8:10:10 PM 45 public Time1Queue(Comparator<Time1> comparator) ( 46 dataQueue new PriorityQueue<>(comparator); 47 48 49 void addTime0bj(Time1 obj) f dataQueue.add(obj); 50 51 52 53 Timel removeTimeobj) ( return dataQueue.remove(); 54 56 57 58 public class Time0bjDemo { 59 public static void main(String[] args) Comparator<Time1> cmpnew Comparator<Time1>() 1e @Override public int compare(Timel ol, Timel o2) long sec1o1.getHour() 3600 o1.getMinute() 60 o1.getSecond( long sec2 o2.getHour() 3600 o2.getMinute() 60 o2.getSecond); return (int) (sec1 - sec2); 6 70 Time!Queue queue new Time!Queue(cmp); queue.addTimeObj(new Time1 (10, 10, 10)); queue.addTimeObj (new Time1 (20, 10, 10)); queue.addTimeObj(new Time1 (10, 30, 30)); queue.addTimeObj (new Time1(13, 10, 10)); queue.addTimeObj(new Time1 (10, 30, 10)); 71 72 73 74 75 76 for(int i-0; i<5; i++) f System.out.println(queue.removeTime0bj)); 78

you can see the times are sorted by their values from low to high.. since low has more priority.
======

import java.util.Comparator;
import java.util.PriorityQueue;

class Time1 {
        private int hour;
        private int minute;
        private int second;

        public Time1(int hour, int minute, int second) {
                if (hour < 0 || hour >= 24 || minute < 0 || minute >= 60 || second < 0 || second >= 60) {
                        throw new IllegalArgumentException("hour, minute and/or second was out of range");
                }

                this.hour = hour;
                this.minute = minute;
                this.second = second;
        }

        public String toUniversalString() {
                return String.format("%02d:%2d:%02d", hour, minute, second);
        }

        public String toString() {
                return String.format("%d:%02d:%02d %s", ((hour == 0 || hour == 12) ? 12 : hour % 12), minute, second,
                                (hour < 12 ? "AM" : "PM"));
        }

        public int getHour() {
                return hour;
        }

        public int getMinute() {
                return minute;
        }

        public int getSecond() {
                return second;
        }
}

class Time1Queue {

        PriorityQueue<Time1> dataQueue;

        public Time1Queue(Comparator<Time1> comparator) {
                dataQueue = new PriorityQueue<>(comparator);
        }

        void addTimeObj(Time1 obj) {
                dataQueue.add(obj);
        }

        Time1 removeTimeObj() {
                return dataQueue.remove();
        }
}

public class TimeObjDemo {

        public static void main(String[] args) {
                Comparator<Time1> cmp = new Comparator<Time1>() {

                        @Override
                        public int compare(Time1 o1, Time1 o2) {
                                long sec1 = o1.getHour() * 3600 + o1.getMinute() * 60 + o1.getSecond();
                                long sec2 = o2.getHour() * 3600 + o2.getMinute() * 60 + o2.getSecond();
                                return (int) (sec1 - sec2);
                        }
                };
                
                Time1Queue queue = new Time1Queue(cmp);
                queue.addTimeObj(new Time1(10, 10, 10));
                queue.addTimeObj(new Time1(20, 10, 10));
                queue.addTimeObj(new Time1(10, 30, 30));
                queue.addTimeObj(new Time1(13, 10, 10));
                queue.addTimeObj(new Time1(10, 30, 10));
                
                for(int i=0; i<5; i++) {
                        System.out.println(queue.removeTimeObj());
                }

        }

}

please upvote. Thanks!