Java-我的二进制堆实现有多好？

Question

I've read a little about binary heaps/priority queues and decided to try my hand at making my own implementation of one. I'm not the most experienced programmer and I would be really grateful if you guys could take a look at my heap class and tell me if it's a good implementation.

What can I improve here? Any feedback is welcome.

public class Heap<T extends Comparable<? super T>> {

    private T[] array = (T[])new Comparable[10];
    private int size = 0;

    public void insert(T data) {
        if(size+1 > array.length) expandArray();

        array[size++] = data;
        int pos = size-1;
        T temp;

        while(pos != 0 && array[pos].compareTo(array[pos/2]) < 0) {
            temp = array[pos/2];
            array[pos/2] = array[pos];
            array[pos] = temp;
            pos /= 2;
        }
    }

    public T deleteMin() {
        T min = array[0];

        array[0] = array[size-1];
        array[size-1] = null;
        size--;
        int pos = 0;
        T temp;
        boolean done = false;

        while(pos*2+1 < size && !done) {
            int minChild = pos*2+1;
            if(array[minChild].compareTo(array[pos*2+2]) > 0) minChild = pos*2+2;

            if(array[pos].compareTo(array[minChild]) > 0) {
                temp = array[minChild];
                array[minChild] = array[pos];
                array[pos] = temp;
                pos = minChild;
            }
            else done = true;
        }

        return min;
    }

    private void expandArray() {
        T[] newArray = (T[])new Comparable[array.length*2];

        for(int i = 0; i < array.length; i++)
            newArray[i] = array[i];

        array = newArray;
    }
}

Answer 1

The best way to answer your question is to write unit tests to test that your implementation is reliable, and to write some performance tests to test that your implementation is reasonably fast. In the process of doing those two things, you'll also find out if your implementation is easy to use.