如何将元素添加到不同类型的 Java 集合的 PriorityQueue 中？

Question

I want to add string and integer elements into a Priority Queue. However,after adding string elements and then integer, the program breaks and gives me error as following: java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Integer

Is it not allowed to have values of multiple types in a single PriorityQueue? What could be the other way around?

My PriorityQueue looks like this:

PriorityQueue queue = new PriorityQueue();

Element to add is as following:

public void addElementToQueue(Object obj) {
        queue.add(obj);
}

Answer 1

I don't know know what logic do you want to follow but it will look like the following code:

 public static void main(String[] args) {
    PriorityQueue<Object> priorityQueue = new PriorityQueue<>(new Comparator<Object>() {

        @Override
        public int compare(Object o1, Object o2) {
            //Your own comparison logic
            return 0;
        }
    });
    priorityQueue.add("Bar");
    priorityQueue.add(2);
    priorityQueue.add(1);
    priorityQueue.add(3);
    priorityQueue.add(4);
    priorityQueue.add("Foo");
    System.out.println(priorityQueue);
}

Please let me know if you need more details.

Thanks