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手写一个HashMap

根据JDK中HashMap的实现原理，手写一个类似的HashMap.

代码

public class MyHashMap 
   
     {
       private int capacity;    private Node
    
     [] table;    public MyHashMap () {
           this.capacity = 16;        this.table = new Node[capacity];    }    public MyHashMap (int capacity) {
           this.capacity = capacity;        this.table = new Node[capacity];    }    public void put(K key, V value) {
           int hashCode = key.hashCode();        int index = hashCode % capacity;        Node
     
       node = new Node<>(key, value);        if (table[index] == null) {
               table[index] = node;        } else {
               Node
      
        cur = table[index];            while (cur.next != null) cur = cur.next;            cur.next = node;        }    }    public V get(K key) {
           int hashCode = key.hashCode();        int index = hashCode % capacity;        Node
       
         cur = table[index];        if (cur == null) return null;        else {
               while (cur != null && !cur.key.equals(key)) cur = cur.next;            if (cur == null) return null;            else return cur.value;        }    }    public static void main(String[] args) {
           MyHashMap
        
          map = new MyHashMap<>(5); map.put("key1", 100); map.put("key2", 200); map.put("key3", 300); map.put("key4", 400); map.put("key5", 500); map.put("key6", 600); int res1 = map.get("key1"); System.out.println(res1); int res6 = map.get("key6"); System.out.println(res6); } static class Node 
         
           { K key; V value; Node
          
            next; public Node(K key, V value) { this.key = key; this.value = value; this.next = null; } }}
          
         
        
       
      
     
    
   

测试结果