php的memcache類分享

 這篇文章主要介紹了php的memcache類的使用方法(memcache隊列),需要的朋友可以參考下

memcacheQueue.class.php  代碼如下:<?php/** * PHP memcache 隊列類 * @author LKK/lianq.net * @version 0.3 * @修改說明: * 1.放棄了之前的AB面輪值思路,使用類似數組的構造,重寫了此類. * 2.隊列預設先進先出,但增加了反向讀取功能. * 3.感謝網友FoxHunter提出的寶貴意見. * @example: * $obj = new memcacheQueue('duilie'); * $obj->add('1asdf'); * $obj->getQueueLength(); * $obj->read(10); * $obj->get(8); */class memcacheQueue{ public static $client;   //memcache用戶端串連 public   $access;   //隊列是否可更新 private   $expire;   //到期時間,秒,1~2592000,即30天內 private   $sleepTime;   //等待解鎖時間,微秒 private   $queueName;   //隊列名稱,唯一值 private   $retryNum;   //重試次數,= 10 * 理論並發數 public   $currentHead;  //當前隊首值 public   $currentTail;  //當前隊尾值  const MAXNUM  = 20000;    //最大隊列數,建議上限10K const HEAD_KEY = '_lkkQueueHead_';  //隊列首kye const TAIL_KEY = '_lkkQueueTail_';  //隊列尾key const VALU_KEY = '_lkkQueueValu_';  //隊列值key const LOCK_KEY = '_lkkQueueLock_';  //隊列鎖key     /**     * 建構函式     * @param string $queueName  隊列名稱     * @param int $expire 到期時間     * @param array $config  memcache配置     *      * @return <type>     */ public function __construct($queueName ='',$expire=0,$config =''){  if(empty($config)){   self::$client = memcache_pconnect('127.0.0.1',11211);  }elseif(is_array($config)){//array('host'=>'127.0.0.1','port'=>'11211')   self::$client = memcache_pconnect($config['host'],$config['port']);  }elseif(is_string($config)){//"127.0.0.1:11211"   $tmp = explode(':',$config);   $conf['host'] = isset($tmp[0]) ? $tmp[0] : '127.0.0.1';   $conf['port'] = isset($tmp[1]) ? $tmp[1] : '11211';   self::$client = memcache_pconnect($conf['host'],$conf['port']);  }  if(!self::$client) return false;   ignore_user_abort(true);//當客戶中斷連線,允許繼續執行  set_time_limit(0);//取消指令碼執行延時上限   $this->access = false;  $this->sleepTime = 1000;  $expire = empty($expire) ? 3600 : intval($expire)+1;  $this->expire = $expire;  $this->queueName = $queueName;  $this->retryNum = 1000;   $this->head_key = $this->queueName . self::HEAD_KEY;  $this->tail_key = $this->queueName . self::TAIL_KEY;  $this->lock_key = $this->queueName . self::LOCK_KEY;   $this->_initSetHeadNTail(); }     /**     * 初始化設定隊列首尾值     */ private function _initSetHeadNTail(){  //當前隊列首的數值  $this->currentHead = memcache_get(self::$client, $this->head_key);  if($this->currentHead === false) $this->currentHead =0;   //當前隊列尾的數值  $this->currentTail = memcache_get(self::$client, $this->tail_key);  if($this->currentTail === false) $this->currentTail =0; }     /**     * 當取出元素時,改變隊列首的數值  * @param int $step 步長值     */ private function _changeHead($step=1){  $this->currentHead += $step;  memcache_set(self::$client, $this->head_key,$this->currentHead,false,$this->expire); }     /**     * 當添加元素時,改變隊列尾的數值  * @param int $step 步長值     * @param bool $reverse 是否反向     * @return null     */ private function _changeTail($step=1, $reverse =false){  if(!$reverse){   $this->currentTail += $step;  }else{   $this->currentTail -= $step;  }   memcache_set(self::$client, $this->tail_key,$this->currentTail,false,$this->expire); }     /**     * 隊列是否為空白     * @return bool     */ private function _isEmpty(){  return (bool)($this->currentHead === $this->currentTail); }     /**     * 隊列是否已滿     * @return bool     */ private function _isFull(){  $len = $this->currentTail - $this->currentHead;  return (bool)($len === self::MAXNUM); }     /**     * 隊列加鎖     */ private function _getLock(){  if($this->access === false){   while(!memcache_add(self::$client, $this->lock_key, 1, false, $this->expire) ){    usleep($this->sleepTime);    @$i++;    if($i > $this->retryNum){//嘗試等待N次     return false;     break;    }   }    $this->_initSetHeadNTail();   return $this->access = true;  }   return $this->access; }     /**     * 隊列解鎖     */ private function _unLock(){  memcache_delete(self::$client, $this->lock_key, 0);  $this->access = false; }     /**     * 擷取當前隊列的長度     * 該長度為理論長度,某些元素由於到期失效而丟失,真實長度<=該長度     * @return int     */ public function getQueueLength(){  $this->_initSetHeadNTail();  return intval($this->currentTail - $this->currentHead); }     /**     * 添加隊列資料     * @param void $data 要添加的資料     * @return bool     */ public function add($data){  if(!$this->_getLock()) return false;   if($this->_isFull()){   $this->_unLock();   return false;  }   $value_key = $this->queueName . self::VALU_KEY . strval($this->currentTail +1);  $result = memcache_set(self::$client, $value_key, $data, MEMCACHE_COMPRESSED, $this->expire);  if($result){   $this->_changeTail();  }   $this->_unLock();  return $result; }     /**     * 讀取隊列資料     * @param int $length 要讀取的長度(反向讀取使用負數)     * @return array     */ public function read($length=0){  if(!is_numeric($length)) return false;  $this->_initSetHeadNTail();   if($this->_isEmpty()){   return false;  }   if(empty($length)) $length = self::MAXNUM;//預設所有  $keyArr = array();  if($length >0){//正向讀取(從隊列首向隊列尾)   $tmpMin = $this->currentHead;   $tmpMax = $tmpMin + $length;   for($i= $tmpMin; $i<=$tmpMax; $i++){    $keyArr[] = $this->queueName . self::VALU_KEY . $i;   }  }else{//反向讀取(從隊列尾向隊列首)   $tmpMax = $this->currentTail;   $tmpMin = $tmpMax + $length;   for($i= $tmpMax; $i >$tmpMin; $i--){    $keyArr[] = $this->queueName . self::VALU_KEY . $i;   }  }   $result = @memcache_get(self::$client, $keyArr);   return $result; }     /**     * 取出隊列資料     * @param int $length 要取出的長度(反向讀取使用負數)     * @return array     */ public function get($length=0){  if(!is_numeric($length)) return false;  if(!$this->_getLock()) return false;   if($this->_isEmpty()){   $this->_unLock();   return false;  }   if(empty($length)) $length = self::MAXNUM;//預設所有  $length = intval($length);  $keyArr = array();  if($length >0){//正向讀取(從隊列首向隊列尾)   $tmpMin = $this->currentHead;   $tmpMax = $tmpMin + $length;   for($i= $tmpMin; $i<=$tmpMax; $i++){    $keyArr[] = $this->queueName . self::VALU_KEY . $i;   }   $this->_changeHead($length);  }else{//反向讀取(從隊列尾向隊列首)   $tmpMax = $this->currentTail;   $tmpMin = $tmpMax + $length;   for($i= $tmpMax; $i >$tmpMin; $i--){    $keyArr[] = $this->queueName . self::VALU_KEY . $i;   }   $this->_changeTail(abs($length), true);  }  $result = @memcache_get(self::$client, $keyArr);   foreach($keyArr as $v){//取出之後刪除   @memcache_delete(self::$client, $v, 0);  }   $this->_unLock();   return $result; }     /**     * 清空隊列     */ public function clear(){  if(!$this->_getLock()) return false;   if($this->_isEmpty()){   $this->_unLock();   return false;  }   $tmpMin = $this->currentHead--;  $tmpMax = $this->currentTail++;   for($i= $tmpMin; $i<=$tmpMax; $i++){   $tmpKey = $this->queueName . self::VALU_KEY . $i;   @memcache_delete(self::$client, $tmpKey, 0);  }   $this->currentTail = $this->currentHead = 0;  memcache_set(self::$client, $this->head_key,$this->currentHead,false,$this->expire);  memcache_set(self::$client, $this->tail_key,$this->currentTail,false,$this->expire);   $this->_unLock(); }  /*  * 清除所有memcache快取資料  */ public function memFlush(){  memcache_flush(self::$client); } }//end class