<?<span>php
</span><span>/*</span><span>
 * hash::拉鏈法解決hash節(jié)點存儲沖突問題
 * ::2014-07-02
 * ::Small_Kind
 </span><span>*/</span>
<span>class</span><span> small_hash {
    
  </span><span>private</span> <span>$size</span> = 20;<span>//</span><span>hash節(jié)點大小</span>
  <span>private</span> <span>$zone</span> = <span>null</span>;<span>//</span><span>hash空間
    
  //實例化函數(shù),并設(shè)置一個初始hash節(jié)點大小，如果節(jié)點大小為null,則為默認(rèn)節(jié)點大小</span>
  <span>final</span> <span>public</span> <span>function</span> __construct(<span>$size</span> = <span>null</span><span>){
    </span><span>if</span>(!<span>is_null</span>(<span>$size</span>))<span>$this</span>->size = <span>$size</span>;<span>//
</span>    <span>$this</span>->zone = <span>new</span> SplFixedArray(<span>$this</span>->size);<span>//
</span><span>  }
  
  </span><span>//</span><span>times33::計算key的hash值,并進(jìn)行節(jié)點大小的取模工作
  //::實現(xiàn)流程1、計算key長度2、循環(huán)長度，并將每個字符轉(zhuǎn)換成asicc碼后*33</span>
  <span>final</span> <span>private</span> <span>function</span> hash_times33(<span>$key</span><span>){
      </span><span>if</span>(<span>empty</span>(<span>$key</span>))<span>return</span> <span>false</span>;<span>//</span><span>key==>empty</span>
      <span>$strlen</span> = <span>strlen</span>(<span>$key</span><span>);
      </span><span>$hash_val</span> = 0<span>;
      </span><span>for</span>(<span>$i</span>=0;<span>$i</span><<span>$strlen</span>;<span>$i</span>++<span>){
          </span><span>$hash_val</span> += (<span>$hash_val</span> * 33) + <span>ord</span>(<span>$key</span>{<span>$i</span><span>});
      }
      </span><span>return</span> (<span>$hash_val</span> & 0x7FFFFFFF) % <span>$this</span>-><span>size;
  }
  
  </span><span>//</span><span>set::通過拉鏈法進(jìn)行key->value對應(yīng)的值設(shè)置</span>
  <span>final</span> <span>public</span> <span>function</span> set(<span>$key</span>,<span>$value</span><span>){
      </span><span>if</span>(<span>empty</span>(<span>$key</span>) || <span>empty</span>(<span>$value</span>))<span>return</span> <span>false</span>;<span>//</span><span>empty</span>
      <span>$index</span> = <span>$this</span>->hash_times33(<span>$key</span><span>);
      </span><span>//</span><span>如果不存在此節(jié)點的數(shù)據(jù)，則向該節(jié)點添加第一組數(shù)據(jù)</span>
      <span>if</span>(<span>isset</span>(<span>$this</span>->zone[<span>$index</span><span>])){
          </span><span>//</span><span>key、value、拉鏈對象[當(dāng)該節(jié)點已存在1個或多組數(shù)據(jù)的時候，將之前的數(shù)據(jù)賦值給最新的一組data]
          //也就是說在查詢時候相當(dāng)于一種后進(jìn)先出的原則,不斷將最新的數(shù)據(jù)放在最前面，以此形成一種階梯形式</span>
          <span>$data</span> = <span>array</span>(<span>$key</span>,<span>serialize</span>(<span>$value</span>),<span>$this</span>->zone[<span>$index</span><span>]);
      }</span><span>else</span><span>{
          </span><span>$data</span> = <span>array</span>(<span>$key</span>,<span>serialize</span>(<span>$value</span>),<span>null</span>);<span>//</span><span>key、value、拉鏈對象[當(dāng)該節(jié)點是第一次有值的時候，拉鏈對象為null]</span>
<span>      }
      </span><span>return</span> <span>$this</span>->zone[<span>$index</span>] = <span>$data</span>;<span>//</span><span>最后將完整的data賦值給該節(jié)點</span>
<span>  }
  
  </span><span>//</span><span>get::通過key獲取對應(yīng)hash后對應(yīng)的的節(jié)點，循環(huán)該對象節(jié)點，然后通過key值匹配節(jié)點中的key，并將值進(jìn)行返回</span>
  <span>final</span> <span>public</span> <span>function</span> get(<span>$key</span><span>){
      </span><span>$index</span>  = <span>$this</span>->hash_times33(<span>$key</span><span>);
      </span><span>$handle</span> = <span>new</span> stdClass();<span>//</span><span>初始化一個對象</span>
      <span>$handle</span> = (<span>array</span>)<span>$this</span>->zone[<span>$index</span>];<span>//</span><span>查詢該key對應(yīng)的節(jié)點</span>
      <span>return</span> <span>$this</span>->for_match(<span>$key</span>,<span>$handle</span>);<span>//</span><span>將對象數(shù)組送入匹配函數(shù)進(jìn)行迭代查詢</span>
<span>  }
  
  </span><span>//</span><span>for_match::通過key對handle進(jìn)行迭代查詢,查詢到了即返回，沒有查詢到則返回一個false</span>
  <span>final</span> <span>public</span> <span>function</span> for_match(<span>$key</span>,<span>$handle</span><span>){
      </span><span>if</span>(<span>is_array</span>(<span>$handle</span><span>)){
          </span><span>if</span>(<span>$handle</span>[0] == <span>$key</span><span>){
              </span><span>return</span> <span>unserialize</span>(<span>$handle</span>[1]);<span>//</span><span>如果找到值了,則對值進(jìn)行返回</span>
          }<span>else</span><span>{
              </span><span>return</span> <span>$this</span>->for_match(<span>$key</span>,<span>$handle</span>[2]);<span>//</span><span>否則繼續(xù)迭代該方法</span>
<span>          }
      }
  }
}

</span><span>$hand</span> = <span>new</span><span> small_hash();
</span><span>$hand</span>->set('Libin','WWW.BAIDU.COM'<span>);
</span><span>$hand</span>->set('d24150ddd','WWW.PHP.COM'<span>);
</span><span>var_dump</span>(<span>$hand</span>->get('Libin'<span>));
</span><span>var_dump</span>(<span>$hand</span>->get('d24150ddd'<span>));
</span>?>

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