CFileCache
| 包 | system.caching |
|---|---|
| 继承 | class CFileCache » CCache » CApplicationComponent » CComponent |
| 实现 | ArrayAccess, ICache, IApplicationComponent |
| 源码 | framework/caching/CFileCache.php |
CFileCache provides a file-based caching mechanism.
For each data value being cached, CFileCache will use store it in a separate file under cachePath which defaults to 'protected/runtime/cache'. CFileCache will perform garbage collection automatically to remove expired cache files.
See CCache manual for common cache operations that are supported by CFileCache.
For each data value being cached, CFileCache will use store it in a separate file under cachePath which defaults to 'protected/runtime/cache'. CFileCache will perform garbage collection automatically to remove expired cache files.
See CCache manual for common cache operations that are supported by CFileCache.
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 |
| cacheFileMode | integer | the permission to be set for new cache files. | CFileCache |
| cacheFileSuffix | string | cache file suffix. | CFileCache |
| cachePath | string | the directory to store cache files. | CFileCache |
| cachePathMode | integer | the permission to be set for directory to store cache files This value will be used by PHP chmod function. | CFileCache |
| directoryLevel | integer | the level of sub-directories to store cache files. | CFileCache |
| embedExpiry | boolean | whether cache entry expiration time should be embedded into a physical file. | CFileCache |
| gCProbability | integer | the probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache. | CFileCache |
| 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 |
| serializer | array|boolean | the functions used to serialize and unserialize cached data. | CCache |
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 |
| gc() | Removes expired cache files. | CFileCache |
| get() | Retrieves a value from cache with a specified key. | CCache |
| getEventHandlers() | Returns the list of attached event handlers for an event. | CComponent |
| getGCProbability() | Returns the probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache. Defaults to 100, meaning 0.01% chance. | CFileCache |
| getIsInitialized() | Checks if this application component has been initialized. | CApplicationComponent |
| 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. | CFileCache |
| 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 |
| setGCProbability() | Sets the probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache. Defaults to 100, meaning 0.01% chance. This number should be between 0 and 1000000. A value 0 meaning no GC will be performed at all. | CFileCache |
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. | CFileCache |
| deleteValue() | Deletes a value with the specified key from cache | CFileCache |
| flushValues() | Deletes all values from cache. | CFileCache |
| generateUniqueKey() | CCache | |
| getCacheFile() | Returns the cache file path given the cache key. | CFileCache |
| getValue() | Retrieves a value from cache with a specified key. | CFileCache |
| getValues() | Retrieves multiple values from cache with the specified keys. | CCache |
| setValue() | Stores a value identified by a key in cache. | CFileCache |
属性详情
cacheFileMode
属性
（自版本 v1.1.16 可用）
public integer $cacheFileMode;
the permission to be set for new cache files. This value will be used by PHP chmod function. Defaults to 0666, meaning the file is read-writable by all users.
cacheFileSuffix
属性
public string $cacheFileSuffix;
cache file suffix. Defaults to '.bin'.
cachePath
属性
public string $cachePath;
the directory to store cache files. Defaults to null, meaning using 'protected/runtime/cache' as the directory.
cachePathMode
属性
（自版本 v1.1.16 可用）
public integer $cachePathMode;
the permission to be set for directory to store cache files This value will be used by PHP chmod function. Defaults to 0777, meaning the directory can be read, written and executed by all users.
directoryLevel
属性
public integer $directoryLevel;
the level of sub-directories to store cache files. Defaults to 0, meaning no sub-directories. If the system has huge number of cache files (e.g. 10K+), you may want to set this value to be 1 or 2 so that the file system is not over burdened. The value of this property should not exceed 16 (less than 3 is recommended).
embedExpiry
属性
（自版本 v1.1.14 可用）
public boolean $embedExpiry;
whether cache entry expiration time should be embedded into a physical file. Defaults to false meaning that the file modification time will be used to store expire value. True value means that first ten bytes of the file would be reserved and used to store expiration time. On some systems PHP is not allowed to change file modification time to be in future even with 777 permissions, so this property could be useful in this case.
gCProbability
属性
the probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache. Defaults to 100, meaning 0.01% chance.
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 |
| $expire | integer | the number of seconds in which the cached value will expire. 0 means never expire. |
| {return} | boolean | true if the value is successfully stored into cache, false otherwise |
源码： framework/caching/CFileCache.php#185 (显示)
protected function addValue($key,$value,$expire)
{
$cacheFile=$this->getCacheFile($key);
if($this->filemtime($cacheFile)>time())
return false;
return $this->setValue($key,$value,$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)
| ||
| $key | string | the key of the value to be deleted |
| {return} | boolean | if no error happens during deletion |
源码： framework/caching/CFileCache.php#199 (显示)
protected function deleteValue($key)
{
$cacheFile=$this->getCacheFile($key);
return @unlink($cacheFile);
}
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/CFileCache.php#117 (显示)
protected function flushValues()
{
$this->gc(false);
return true;
}
Deletes all values from cache. This is the implementation of the method declared in the parent class.
gc()
方法
|
public void gc(boolean $expiredOnly=true, string $path=NULL)
| ||
| $expiredOnly | boolean | whether only expired cache files should be removed. If false, all cache files under cachePath will be removed. |
| $path | string | the path to clean with. If null, it will be cachePath. |
源码： framework/caching/CFileCache.php#232 (显示)
public function gc($expiredOnly=true,$path=null)
{
if($path===null)
$path=$this->cachePath;
if(($handle=opendir($path))===false)
return;
while(($file=readdir($handle))!==false)
{
if($file[0]==='.')
continue;
$fullPath=$path.DIRECTORY_SEPARATOR.$file;
if(is_dir($fullPath))
$this->gc($expiredOnly,$fullPath);
elseif($expiredOnly && $this->filemtime($fullPath)<time() || !$expiredOnly)
@unlink($fullPath);
}
closedir($handle);
}
Removes expired cache files.
getCacheFile()
方法
|
protected string getCacheFile(string $key)
| ||
| $key | string | cache key |
| {return} | string | the cache file path |
源码： framework/caching/CFileCache.php#210 (显示)
protected function getCacheFile($key)
{
if($this->directoryLevel>0)
{
$base=$this->cachePath;
for($i=0;$i<$this->directoryLevel;++$i)
{
if(($prefix=substr($key,$i+$i,2))!==false)
$base.=DIRECTORY_SEPARATOR.$prefix;
}
return $base.DIRECTORY_SEPARATOR.$key.$this->cacheFileSuffix;
}
else
return $this->cachePath.DIRECTORY_SEPARATOR.$key.$this->cacheFileSuffix;
}
Returns the cache file path given the cache key.
getGCProbability()
方法
|
public integer getGCProbability()
| ||
| {return} | integer | the probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache. Defaults to 100, meaning 0.01% chance. |
源码： framework/caching/CFileCache.php#91 (显示)
public function getGCProbability()
{
return $this->_gcProbability;
}
getValue()
方法
|
protected string|boolean getValue(string $key)
| ||
| $key | string | a unique key identifying the cached value |
| {return} | string|boolean | the value stored in cache, false if the value is not in the cache or expired. |
源码： framework/caching/CFileCache.php#129 (显示)
protected function getValue($key)
{
$cacheFile=$this->getCacheFile($key);
if(($time=$this->filemtime($cacheFile))>time())
return @file_get_contents($cacheFile,false,null,$this->embedExpiry ? 10 : null);
elseif($time>0)
@unlink($cacheFile);
return false;
}
Retrieves a value from cache with a specified key. This is the implementation of the method declared in the parent class.
init()
方法
|
public void init()
|
源码： framework/caching/CFileCache.php#75 (显示)
public function init()
{
parent::init();
if($this->cachePath===null)
$this->cachePath=Yii::app()->getRuntimePath().DIRECTORY_SEPARATOR.'cache';
if(!is_dir($this->cachePath))
{
mkdir($this->cachePath,$this->cachePathMode,true);
chmod($this->cachePath,$this->cachePathMode);
}
}
Initializes this application component. This method is required by the IApplicationComponent interface.
setGCProbability()
方法
|
public void setGCProbability(integer $value)
| ||
| $value | integer | the probability (parts per million) that garbage collection (GC) should be performed when storing a piece of data in the cache. Defaults to 100, meaning 0.01% chance. This number should be between 0 and 1000000. A value 0 meaning no GC will be performed at all. |
源码： framework/caching/CFileCache.php#101 (显示)
public function setGCProbability($value)
{
$value=(int)$value;
if($value<0)
$value=0;
if($value>1000000)
$value=1000000;
$this->_gcProbability=$value;
}
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 |
| $expire | integer | the number of seconds in which the cached value will expire. 0 means never expire. |
| {return} | boolean | true if the value is successfully stored into cache, false otherwise |
源码： framework/caching/CFileCache.php#148 (显示)
protected function setValue($key,$value,$expire)
{
if(!$this->_gced && mt_rand(0,1000000)<$this->_gcProbability)
{
$this->gc();
$this->_gced=true;
}
if($expire<=0)
$expire=31536000; // 1 year
$expire+=time();
$cacheFile=$this->getCacheFile($key);
if($this->directoryLevel>0)
{
$cacheDir=dirname($cacheFile);
@mkdir($cacheDir,$this->cachePathMode,true);
@chmod($cacheDir,$this->cachePathMode);
}
if(@file_put_contents($cacheFile,$this->embedExpiry ? $expire.$value : $value,LOCK_EX)!==false)
{
@chmod($cacheFile,$this->cacheFileMode);
return $this->embedExpiry ? true : @touch($cacheFile,$expire);
}
else
return false;
}
Stores a value identified by a key in cache. This is the implementation of the method declared in the parent class.