簡單的HashMap實現

/**
 * 借鑑自HashMap源碼
 */
class MyHashMap {

    private int sizeOfTable = 1024;
    private Node[] table = new Node[sizeOfTable];

    private class Node {
        public int key;
        public int value;
        public Node next;

        public Node(int key, int value) {
            this.key = key;
            this.value = value;
        }
    }

    public void put(int key, int value) {
        int hash = Objects.hashCode(key);
        int pos = hash & (sizeOfTable - 1);
        Node p;
        if ((p = table[pos]) == null) {
            table[pos] = new Node(key, value);
        } else if (p.key == key) {
            p.value = value;
        } else {
            Node pre;
            do {
                pre = p;
                p = p.next;
            } while (p != null && p.key != key);

            if (p == null) {
                pre.next = new Node(key, value);
            } else {
                p.value = value;
            }
        }
    }

    public int get(int key) {
        int hash = Objects.hashCode(key);
        int pos = hash & (sizeOfTable - 1);
        Node p = table[pos];
        while (p != null && p.key != key) {
            p = p.next;
        }

        return p == null ? -1 : p.value;
    }

    public void remove(int key) {
        int hash = Objects.hashCode(key);
        int pos = hash & (sizeOfTable - 1);
        Node p = table[pos];
        if (p == null) {
            return;
        }

        if (p.key == key) {
            table[pos] = p.next;
        } else {
            Node pre;
            do {
                pre = p;
                p = p.next;
            } while (p != null && p.key != key);

            if (p != null) {
                pre.next = p.next;
            }
        }
    }
}