Errors using the Comparator Interface


I am trying to write a simple application with priority queues. I am getting the following errors --" error: leastPriority is not abstract and does not override abstract method compare(Integer,Integer) in Comparator" and "error: incompatible types Comparator cmp = new leastPriority(); "

Can someone point out the problem with this code.

My code is :

class leastPriority implements Comparator<Integer> {
    public int compare(Reservation x, Reservation y){
        if(x.getPriority() > y.getPriority()){
            return -1;
        if(x.getPriority() < y.getPriority()){
            return +1;
        return 0;

public class prioQueue{

    public static void main(String args[]){
        Comparator<Reservation> cmp = new leastPriority();
        PriorityQueue<Reservation> queue = new PriorityQueue<Reservation>(10,cmp);
        queue.add(new Reservation(1,"Andy",10));
        queue.add(new Reservation(1,"Peter",1));
        queue.add(new Reservation(1,"John",4));

            Reservation r = queue.poll();


Your type parameter for Comparator<T> and your compare(T o1, T o2) method's parameters does not match. Since in the interface they are the same, you need to give identical types to them.

Change this:

class leastPriority implements Comparator<Integer>


class leastPriority implements Comparator<Reservation>