Priority Queues

//Patient class having patient name and priority public class Patient {

private int patientPriority;
private String patientName;
private int patientId;

public Patient(int id,String name,int priority ){		
	this.patientName=name;
	this.patientPriority=priority;
	this.patientId = id;
}

public int getPriority() {
	
	return patientPriority;
}

public int getId() {

	return patientId;
}
public String getName() {
	
	return patientName;
}

} //Priority queue comparator to decide the //emergency patient import java.util.Comparator;

public class PatientPriorityComparator implements Comparator {

@Override
public int compare(Patient patient, Patient priorityPatient) {

	// comparison code for Patients on the basis of emergency
	Patient p1 = (Patient) patient;
	Patient p2 = (Patient) priorityPatient;	
	//1 dscending
	//-1		asscending
	

	 if (p1.getPriority() < p2.getPriority()) return 1; if (p1.getPriority() > p2.getPriority())
	        return -1;
	    else { if (p1.getId() <(p2.getId())) return -1; if (p1.getId() > (p2.getId()))
	        return 1;
	    }
	    return 0; 

}	

}

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

//Test program for Priority queue //Add and remove patient on run time and will //manage priority queue. public class PriorityQueueExample {

public static void main(String[] args) {

	// Priority
	// NORMAL 1
	// Emergency 2

	boolean exit = false;

	String pName;
	int pPriority;
	int pId;
	//Create Patient priority comparator, so, 
	//priorityQueue class can decide
	//whom to put on head of the list.
	Comparator queueComparator = new PatientPriorityComparator();
	
	//Create a priory queue and assign a comparator to its constructor.
	//Set the initial capacity of the queue to 10 or something.
	PriorityQueue priorityQueue = new PriorityQueue(10,
			queueComparator);

	do {
		//Display options for input data, display list
		// and exit application
		System.out.println("1.Input");
		System.out.println("2.Display list");
		System.out.println("3.Exit");
		
		//Read option from console
		Scanner option = new Scanner(System.in);
		System.out.println("enter your choice");
		int num = option.nextInt();
		
		switch (num) {
		case 1:
			//Enter patient name and priority
			Scanner input = new Scanner(System.in);
			System.out.println("Enter Patient ID:");
			pId = (input.nextInt());
			input.nextLine();
			System.out.println("Enter Patient name:");
			pName = input.nextLine();
			System.out.println("Enter priority:");
			pPriority = (input.nextInt());

			Patient obj = new Patient(pId,pName, pPriority);
			priorityQueue.add(obj);
			break;

		case 2:
			//Display patients list1
			
			while (priorityQueue.size() != 0) {
				//poll () method will display the list 
				// and remove head element from the list.
				System.out.println("Patient\t"
						+ priorityQueue.poll().getName());
			}
			break;

		case 3:
			exit = true;
			break;
		}
	} while (!exit);

}

}