AbstractHeap.java

package com.ds_algo.l_heap;

import java.util.Comparator;

@SuppressWarnings({"unchecked","unused"})
public abstract class AbstractHeap<E> implements Heap<E>{
    protected int size;
    protected Comparator<E> comparator;

    public AbstractHeap(Comparator<E> comparator) {
        this.comparator = comparator;
    }
    public AbstractHeap(){
        this(null);
    }

    @Override
    public int size() {
        return size;
    }

    @Override
    public boolean isEmpty() {
        return size == 0;
    }

    protected void emptyCheck(){
        if (size == 0){
            throw new IndexOutOfBoundsException("Heap is empty");
        }
    }
    protected void elementNotNullCheck(E element){
        if (element == null){
            throw new IllegalArgumentException("element must not be null");
        }
    }

    protected int compare(E e1, E e2) {
        return comparator != null ? comparator.compare(e1,e2) : ((Comparable<E>)e1).compareTo(e2);
    }
}