hashmap手写代码

好的，我可以回答这个问题。HashMap 是一种常用的数据结构，它可以用来存储键值对。以下是一个简单的手写 HashMap 代码示例：

public class MyHashMap<K, V> {
    private static final int DEFAULT_CAPACITY = 16;
    private static final float DEFAULT_LOAD_FACTOR = .75f;

    private Entry<K, V>[] table;
    private int size;
    private int capacity;
    private float loadFactor;

    public MyHashMap() {
        this(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR);
    }

    public MyHashMap(int capacity, float loadFactor) {
        this.capacity = capacity;
        this.loadFactor = loadFactor;
        table = new Entry[capacity];
    }

    public void put(K key, V value) {
        int index = hash(key);
        Entry<K, V> entry = table[index];
        while (entry != null) {
            if (entry.key.equals(key)) {
                entry.value = value;
                return;
            }
            entry = entry.next;
        }
        Entry<K, V> newEntry = new Entry<>(key, value);
        newEntry.next = table[index];
        table[index] = newEntry;
        size++;
        if (size > capacity * loadFactor) {
            resize();
        }
    }

    public V get(K key) {
        int index = hash(key);
        Entry<K, V> entry = table[index];
        while (entry != null) {
            if (entry.key.equals(key)) {
                return entry.value;
            }
            entry = entry.next;
        }
        return null;
    }

    public void remove(K key) {
        int index = hash(key);
        Entry<K, V> prev = null;
        Entry<K, V> entry = table[index];
        while (entry != null) {
            if (entry.key.equals(key)) {
                if (prev == null) {
                    table[index] = entry.next;
                } else {
                    prev.next = entry.next;
                }
                size--;
                return;
            }
            prev = entry;
            entry = entry.next;
        }
    }

    private int hash(K key) {
        return key.hashCode() % capacity;
    }

    private void resize() {
        capacity *= 2;
        Entry<K, V>[] newTable = new Entry[capacity];
        for (Entry<K, V> entry : table) {
            while (entry != null) {
                Entry<K, V> next = entry.next;
                int index = hash(entry.key);
                entry.next = newTable[index];
                newTable[index] = entry;
                entry = next;
            }
        }
        table = newTable;
    }

    private static class Entry<K, V> {
        K key;
        V value;
        Entry<K, V> next;

        public Entry(K key, V value) {
            this.key = key;
            this.value = value;
        }
    }
}

这个 HashMap 实现了 put、get 和 remove 方法，它使用链表来解决哈希冲突，同时也支持动态扩容。