CMemCache
| 包 | system.caching |
|---|---|
| 继承 | class CMemCache » CCache » CApplicationComponent » CComponent |
| 实现 | ArrayAccess, ICache, IApplicationComponent |
| 可用自 | 1.0 |
| 源码 | framework/caching/CMemCache.php |
CMemCache implements a cache application component based on memcached.
CMemCache can be configured with a list of memcache servers by settings its servers property. By default, CMemCache assumes there is a memcache server running on localhost at port 11211.
See CCache manual for common cache operations that are supported by CMemCache.
Note, there is no security measure to protected data in memcache. All data in memcache can be accessed by any process running in the system.
To use CMemCache as the cache application component, configure the application as follows,
CMemCache can also be used with memcached. To do so, set useMemcached to be true.
CMemCache can be configured with a list of memcache servers by settings its servers property. By default, CMemCache assumes there is a memcache server running on localhost at port 11211.
See CCache manual for common cache operations that are supported by CMemCache.
Note, there is no security measure to protected data in memcache. All data in memcache can be accessed by any process running in the system.
To use CMemCache as the cache application component, configure the application as follows,
array(
'components'=>array(
'cache'=>array(
'class'=>'CMemCache',
'servers'=>array(
array(
'host'=>'server1',
'port'=>11211,
'weight'=>60,
),
array(
'host'=>'server2',
'port'=>11211,
'weight'=>40,
),
),
),
),
)
In the above, two memcache servers are used: server1 and server2.
You can configure more properties of every server, including:
host, port, persistent, weight, timeout, retryInterval, status.
See http://www.php.net/manual/en/function.memcache-addserver.php
for more details.
CMemCache can also be used with memcached. To do so, set useMemcached to be true.
公共属性
| 属性 | 类型 | 描述 | 被定义在 |
|---|---|---|---|
| behaviors | array | the behaviors that should be attached to this component. | CApplicationComponent |
| hashKey | boolean | whether to md5-hash the cache key for normalization purposes. | CCache |
| isInitialized | boolean | Checks if this application component has been initialized. | CApplicationComponent |
| keyPrefix | string | a string prefixed to every cache key so that it is unique. | CCache |
| memCache | Memcache|Memcached | the memcache instance (or memcached if useMemcached is true) used by this component. | CMemCache |
| serializer | array|boolean | the functions used to serialize and unserialize cached data. | CCache |
| servers | array | list of memcache server configurations. | CMemCache |
| useMemcached | boolean | whether to use memcached or memcache as the underlying caching extension. | CMemCache |
公共方法
| 方法 | 描述 | 被定义在 |
|---|---|---|
| __call() | Calls the named method which is not a class method. | CComponent |
| __get() | Returns a property value, an event handler list or a behavior based on its name. | CComponent |
| __isset() | Checks if a property value is null. | CComponent |
| __set() | Sets value of a component property. | CComponent |
| __unset() | Sets a component property to be null. | CComponent |
| add() | Stores a value identified by a key into cache if the cache does not contain this key. | CCache |
| asa() | Returns the named behavior object. | CComponent |
| attachBehavior() | Attaches a behavior to this component. | CComponent |
| attachBehaviors() | Attaches a list of behaviors to the component. | CComponent |
| attachEventHandler() | Attaches an event handler to an event. | CComponent |
| canGetProperty() | Determines whether a property can be read. | CComponent |
| canSetProperty() | Determines whether a property can be set. | CComponent |
| delete() | Deletes a value with the specified key from cache | CCache |
| detachBehavior() | Detaches a behavior from the component. | CComponent |
| detachBehaviors() | Detaches all behaviors from the component. | CComponent |
| detachEventHandler() | Detaches an existing event handler. | CComponent |
| disableBehavior() | Disables an attached behavior. | CComponent |
| disableBehaviors() | Disables all behaviors attached to this component. | CComponent |
| enableBehavior() | Enables an attached behavior. | CComponent |
| enableBehaviors() | Enables all behaviors attached to this component. | CComponent |
| evaluateExpression() | Evaluates a PHP expression or callback under the context of this component. | CComponent |
| flush() | Deletes all values from cache. | CCache |
| get() | Retrieves a value from cache with a specified key. | CCache |
| getEventHandlers() | Returns the list of attached event handlers for an event. | CComponent |
| getIsInitialized() | Checks if this application component has been initialized. | CApplicationComponent |
| getMemCache() | Returns the memcache instance (or memcached if useMemcached is true) used by this component. | CMemCache |
| getServers() | Returns list of memcache server configurations. Each element is a CMemCacheServerConfiguration. | CMemCache |
| hasEvent() | Determines whether an event is defined. | CComponent |
| hasEventHandler() | Checks whether the named event has attached handlers. | CComponent |
| hasProperty() | Determines whether a property is defined. | CComponent |
| init() | Initializes this application component. | CMemCache |
| mget() | Retrieves multiple values from cache with the specified keys. | CCache |
| offsetExists() | Returns whether there is a cache entry with a specified key. | CCache |
| offsetGet() | Retrieves the value from cache with a specified key. | CCache |
| offsetSet() | Stores the value identified by a key into cache. | CCache |
| offsetUnset() | Deletes the value with the specified key from cache | CCache |
| raiseEvent() | Raises an event. | CComponent |
| set() | Stores a value identified by a key into cache. | CCache |
| setServers() | Sets list of memcache server configurations. Each element must be an array with the following keys: host, port, persistent, weight, timeout, retryInterval, status. | CMemCache |
受保护的方法
| 方法 | 描述 | 被定义在 |
|---|---|---|
| addValue() | Stores a value identified by a key into cache if the cache does not contain this key. | CMemCache |
| deleteValue() | Deletes a value with the specified key from cache | CMemCache |
| flushValues() | Deletes all values from cache. | CMemCache |
| generateUniqueKey() | CCache | |
| getValue() | Retrieves a value from cache with a specified key. | CMemCache |
| getValues() | Retrieves multiple values from cache with the specified keys. | CMemCache |
| setValue() | Stores a value identified by a key in cache. | CMemCache |
属性详情
memCache
属性
只读
public Memcache|Memcached getMemCache()
the memcache instance (or memcached if useMemcached is true) used by this component.
servers
属性
list of memcache server configurations. Each element is a CMemCacheServerConfiguration.
useMemcached
属性
public boolean $useMemcached;
whether to use memcached or memcache as the underlying caching extension. If true memcached will be used. If false memcache. will be used. Defaults to false.
方法详情
addValue()
方法
|
protected boolean addValue(string $key, string $value, integer $expire)
| ||
| $key | string | the key identifying the value to be cached |
| $value | string | the value to be cached |
| $expire | integer | the number of seconds in which the cached value will expire. 0 means never expire. |
| {return} | boolean | true if the value is successfully stored into cache, false otherwise |
源码： framework/caching/CMemCache.php#190 (显示)
protected function addValue($key,$value,$expire)
{
if($expire>0)
$expire+=time();
else
$expire=0;
return $this->useMemcached ? $this->_cache->add($key,$value,$expire) : $this->_cache->add($key,$value,0,$expire);
}
Stores a value identified by a key into cache if the cache does not contain this key. This is the implementation of the method declared in the parent class.
deleteValue()
方法
|
protected boolean deleteValue(string $key)
| ||
| $key | string | the key of the value to be deleted |
| {return} | boolean | if no error happens during deletion |
源码： framework/caching/CMemCache.php#206 (显示)
protected function deleteValue($key)
{
return $this->_cache->delete($key, 0);
}
Deletes a value with the specified key from cache This is the implementation of the method declared in the parent class.
flushValues()
方法
（自版本 v1.1.5 可用）
|
protected boolean flushValues()
| ||
| {return} | boolean | whether the flush operation was successful. |
源码： framework/caching/CMemCache.php#217 (显示)
protected function flushValues()
{
return $this->_cache->flush();
}
Deletes all values from cache. This is the implementation of the method declared in the parent class.
getMemCache()
方法
|
public Memcache|Memcached getMemCache()
| ||
| {return} | Memcache|Memcached | the memcache instance (or memcached if useMemcached is true) used by this component. |
源码： framework/caching/CMemCache.php#108 (显示)
public function getMemCache()
{
if($this->_cache!==null)
return $this->_cache;
else
{
$extension=$this->useMemcached ? 'memcached' : 'memcache';
if(!extension_loaded($extension))
throw new CException(Yii::t('yii',"CMemCache requires PHP {extension} extension to be loaded.",
array('{extension}'=>$extension)));
return $this->_cache=$this->useMemcached ? new Memcached : new Memcache;
}
}
getServers()
方法
|
public array getServers()
| ||
| {return} | array | list of memcache server configurations. Each element is a CMemCacheServerConfiguration. |
getValue()
方法
|
protected string|boolean getValue(string $key)
| ||
| $key | string | a unique key identifying the cached value |
| {return} | string|boolean | the value stored in cache, false if the value is not in the cache or expired. |
源码： framework/caching/CMemCache.php#147 (显示)
protected function getValue($key)
{
return $this->_cache->get($key);
}
Retrieves a value from cache with a specified key. This is the implementation of the method declared in the parent class.
getValues()
方法
|
protected array getValues(array $keys)
| ||
| $keys | array | a list of keys identifying the cached values |
| {return} | array | a list of cached values indexed by the keys |
源码： framework/caching/CMemCache.php#157 (显示)
protected function getValues($keys)
{
return $this->useMemcached ? $this->_cache->getMulti($keys) : $this->_cache->get($keys);
}
Retrieves multiple values from cache with the specified keys.
init()
方法
|
public void init()
|
源码： framework/caching/CMemCache.php#85 (显示)
public function init()
{
parent::init();
$servers=$this->getServers();
$cache=$this->getMemCache();
if(count($servers))
{
foreach($servers as $server)
{
if($this->useMemcached)
$cache->addServer($server->host,$server->port,$server->weight);
else
$cache->addServer($server->host,$server->port,$server->persistent,$server->weight,$server->timeout,$server->retryInterval,$server->status);
}
}
else
$cache->addServer('localhost',11211);
}
Initializes this application component. This method is required by the IApplicationComponent interface. It creates the memcache instance and adds memcache servers.
setServers()
方法
|
public void setServers(array $config)
| ||
| $config | array | list of memcache server configurations. Each element must be an array with the following keys: host, port, persistent, weight, timeout, retryInterval, status. |
源码： framework/caching/CMemCache.php#135 (显示)
public function setServers($config)
{
foreach($config as $c)
$this->_servers[]=new CMemCacheServerConfiguration($c);
}
setValue()
方法
|
protected boolean setValue(string $key, string $value, integer $expire)
| ||
| $key | string | the key identifying the value to be cached |
| $value | string | the value to be cached |
| $expire | integer | the number of seconds in which the cached value will expire. 0 means never expire. |
| {return} | boolean | true if the value is successfully stored into cache, false otherwise |
源码： framework/caching/CMemCache.php#171 (显示)
protected function setValue($key,$value,$expire)
{
if($expire>0)
$expire+=time();
else
$expire=0;
return $this->useMemcached ? $this->_cache->set($key,$value,$expire) : $this->_cache->set($key,$value,0,$expire);
}
Stores a value identified by a key in cache. This is the implementation of the method declared in the parent class.