PHP Memcached + APC + 文件缓存封装

snake_l

　　使用方法：
　　Memcached
　　$cache = new Cache_MemCache();   
$cache->addServer('www1');     
$cache->addServer('www2',11211,20); // this server has double the memory, and gets double the weight     
$cache->addServer('www3',11211);     
// Store some data in the cache for 10 minutes     
$cache->store('my_key','foobar',600);     
// Get it out of the cache again     
echo($cache->fetch('my_key'));
　　文件缓存
　　$cache = new Cache_File();   
$key = 'getUsers:selectAll';     
// check if the data is not in the cache already     
if (!$data = $cache->fetch($key)) {     
// assuming there is a database connection     
$result = mysql_query("SELECT * FROM users");     
$data = array();     
// fetching all the data and putting it in an array     
while($row = mysql_fetch_assoc($result)) { $data[] = $row; }     
// Storing the data in the cache for 10 minutes     
$cache->store($key,$data,600);     
}
　　class_cache3.php
　　<?php   
abstract class Cache_Abstract {     
abstract function fetch($key);     
abstract function store($key, $data, $ttl);     
abstract function delete($key);     
}     
class Cache_APC extends Cache_Abstract {     
function fetch($key) {     
return apc_fetch($key);     
}     
function store($key, $data, $ttl) {     
return apc_store($key, $data, $ttl);     
}     
function delete($key) {     
return apc_delete($key);     
}     
}     
class Cache_MemCache extends Cache_Abstract {     
public $connection;     
function __construct() {     
$this->connection = new MemCache;     
}     
function store($key, $data, $ttl) {     
return $this->connection->set($key, $data, 0, $ttl);     
}     
function fetch($key) {     
return $this->connection->get($key);     
}     
function delete($key) {     
return $this->connection->delete($key);     
}     
function addServer($host, $port = 11211, $weight = 10) {     
$this->connection->addServer($host, $port, true, $weight);     
}     
}     
class Cache_File extends Cache_Abstract {     
function store($key, $data, $ttl) {     
$h = fopen($this->getFileName($key), 'a+');     
if (!$h)     
throw new Exception('Could not write to cache');     
flock($h, LOCK_EX);     
fseek($h, 0);     
ftruncate($h, 0);     
$data = serialize(array(time() + $ttl, $data));     
if (fwrite($h, $data) === false) {     
throw new Exception('Could not write to cache');     
}     
fclose($h);     
}     
function fetch($key) {     
$filename = $this->getFileName($key);     
if (!file_exists($filename))     
return false;     
$h = fopen($filename, 'r');     
if (!$h)     
return false;     
flock($h, LOCK_SH);     
$data = file_get_contents($filename);     
fclose($h);     
$data = @ unserialize($data);     
if (!$data) {     
unlink($filename);     
return false;     
}     
if (time() > $data[0]) {     
unlink($filename);     
return false;     
}     
return $data[1];     
}     
function delete($key) {     
$filename = $this->getFileName($key);     
if (file_exists($filename)) {     
return unlink($filename);     
}     
else {     
return false;     
}     
}     
private function getFileName($key) {     
return '/tmp/s_cache' . md5($key);     
}     
}     
?>