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/CakePHP 3.4

Class NullEngine

Null cache engine, all operations return false.

This is used internally for when Cache::disable() has been called.

Cake\Cache\CacheEngine uses Cake\Core\InstanceConfigTrait
Extended by Cake\Cache\Engine\NullEngine

Inherited Properties

Method Summary

  • clear() public
    Delete all keys from the cache
  • clearGroup() public

    Clears all values belonging to a group. Is up to the implementing engine to decide whether actually delete the keys or just simulate it to achieve the same result.

  • decrement() public
    Decrement a number under the key and return decremented value
  • delete() public
    Delete a key from the cache
  • deleteMany() public
    Deletes keys from the cache
  • gc() public
    Garbage collection
  • increment() public
    Increment a number under the key and return incremented value
  • init() public
    Initialize the cache engine
  • read() public
    Read a key from the cache
  • readMany() public
    Read multiple keys from the cache
  • write() public
    Write value for a key into cache
  • writeMany() public
    Write data for many keys into cache

Method Detail

clear()source public

clear( boolean $check )

Delete all keys from the cache

Parameters

boolean $check
if true will check expiration, otherwise delete all

Returns

boolean
True if the cache was successfully cleared, false otherwise

clearGroup()source public

clearGroup( string $group )

Clears all values belonging to a group. Is up to the implementing engine to decide whether actually delete the keys or just simulate it to achieve the same result.

Parameters

string $group
name of the group to be cleared

Returns

boolean

Overrides

Cake\Cache\CacheEngine::clearGroup()

decrement()source public

decrement( string $key , integer $offset 1 )

Decrement a number under the key and return decremented value

Parameters

string $key
Identifier for the data
integer $offset optional 1
How much to subtract

Returns

boolean|integer
New incremented value, false otherwise

delete()source public

delete( string $key )

Delete a key from the cache

Parameters

string $key
Identifier for the data

Returns

boolean
True if the value was successfully deleted, false if it didn't exist or couldn't be removed

deleteMany()source public

deleteMany( array $keys )

Deletes keys from the cache

Parameters

array $keys
An array of identifiers for the data

Returns

array

For each provided cache key (given back as the array key) true if the value was successfully deleted, false if it didn't exist or couldn't be removed


Overrides

Cake\Cache\CacheEngine::deleteMany()

gc()source public

gc( integer|null $expires null )

Garbage collection

Parameters

integer|null $expires optional null
[optional] An expires timestamp, invalidating all data before.

Overrides

Cake\Cache\CacheEngine::gc()

increment()source public

increment( string $key , integer $offset 1 )

Increment a number under the key and return incremented value

Parameters

string $key
Identifier for the data
integer $offset optional 1
How much to add

Returns

boolean|integer
New incremented value, false otherwise

init()source public

init( array $config [] )

Initialize the cache engine

Parameters

array $config optional []
Associative array of parameters for the engine

Returns

boolean
True if the engine has been successfully initialized, false if not

Overrides

Cake\Cache\CacheEngine::init()

read()source public

read( string $key )

Read a key from the cache

Parameters

string $key
Identifier for the data

Returns

mixed
The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it

readMany()source public

readMany( array $keys )

Read multiple keys from the cache

Parameters

array $keys
An array of identifiers for the data

Returns

array

For each cache key (given as the array key) the cache data associated or false if the data doesn't exist, has expired, or if there was an error fetching it


Overrides

Cake\Cache\CacheEngine::readMany()

write()source public

write( string $key , mixed $value )

Write value for a key into cache

Parameters

string $key
Identifier for the data
mixed $value
Data to be cached

Returns

boolean
True if the data was successfully cached, false on failure

writeMany()source public

writeMany( array $data )

Write data for many keys into cache

Parameters

array $data
An array of data to be stored in the cache

Returns

array
of bools for each key provided, true if the data was successfully cached, false on failure

Overrides

Cake\Cache\CacheEngine::writeMany()

Methods inherited from Cake\Cache\CacheEngine

_key()source protected

_key( string $key )

Generates a safe key, taking account of the configured key prefix

Parameters

string $key
the key passed over

Returns

mixed
string $key or false

Throws

InvalidArgumentException
If key's value is empty

add()source public

add( string $key , mixed $value )

Add a key to the cache if it does not already exist.

Defaults to a non-atomic implementation. Subclasses should prefer atomic implementations.

Parameters

string $key
Identifier for the data.
mixed $value
Data to be cached.

Returns

boolean
True if the data was successfully cached, false on failure.

groups()source public

groups( )

Does whatever initialization for each group is required and returns the group value for each of them, this is the token representing each group in the cache key

Returns

array

key()source public

key( string $key )

Generates a safe key for use with cache engine storage engines.

Parameters

string $key
the key passed over

Returns

boolean|string
string key or false

Methods used from Cake\Core\InstanceConfigTrait

_configDelete()source protected

_configDelete( string $key )

Deletes a single config key.

Parameters

string $key
Key to delete.

Throws

Cake\Core\Exception\Exception
if attempting to clobber existing config

_configRead()source protected

_configRead( string|null $key )

Reads a config key.

Parameters

string|null $key
Key to read.

Returns

mixed

_configWrite()source protected

_configWrite( string|array $key , mixed $value , boolean|string $merge false )

Writes a config key.

Parameters

string|array $key
Key to write to.
mixed $value
Value to write.
boolean|string $merge optional false

True to merge recursively, 'shallow' for simple merge, false to overwrite, defaults to false.

Throws

Cake\Core\Exception\Exception
if attempting to clobber existing config

config()source public

config( string|array|null $key null , mixed|null $value null , boolean $merge true )

Gets/Sets the config.

Usage

Reading the whole config:

$this->config();

Reading a specific value:

$this->config('key');

Reading a nested value:

$this->config('some.nested.key');

Setting a specific value:

$this->config('key', $value);

Setting a nested value:

$this->config('some.nested.key', $value);

Updating multiple config settings at the same time:

$this->config(['one' => 'value', 'another' => 'value']);

Deprecated

3.4.0 use setConfig()/getConfig() instead.

Parameters

string|array|null $key optional null
The key to get/set, or a complete array of configs.
mixed|null $value optional null
The value to set.
boolean $merge optional true
Whether to recursively merge or overwrite existing config, defaults to true.

Returns

mixed
Config value being read, or the object itself on write operations.

Throws

Cake\Core\Exception\Exception
When trying to set a key that is invalid.

configShallow()source public

configShallow( string|array $key , mixed|null $value null )

Merge provided config with existing config. Unlike config() which does a recursive merge for nested keys, this method does a simple merge.

Setting a specific value:

$this->config('key', $value);

Setting a nested value:

$this->config('some.nested.key', $value);

Updating multiple config settings at the same time:

$this->config(['one' => 'value', 'another' => 'value']);

Parameters

string|array $key
The key to set, or a complete array of configs.
mixed|null $value optional null
The value to set.

Returns


$this

getConfig()source public

getConfig( string|null $key null )

Returns the config.

Usage

Reading the whole config:

$this->getConfig();

Reading a specific value:

$this->getConfig('key');

Reading a nested value:

$this->getConfig('some.nested.key');

Parameters

string|null $key optional null
The key to get or null for the whole config.

Returns

mixed
Config value being read.

setConfig()source public

setConfig( string|array $key , mixed|null $value null , boolean $merge true )

Sets the config.

Usage

Setting a specific value:

$this->setConfig('key', $value);

Setting a nested value:

$this->setConfig('some.nested.key', $value);

Updating multiple config settings at the same time:

$this->setConfig(['one' => 'value', 'another' => 'value']);

Parameters

string|array $key
The key to set, or a complete array of configs.
mixed|null $value optional null
The value to set.
boolean $merge optional true
Whether to recursively merge or overwrite existing config, defaults to true.

Returns


$this

Throws

Cake\Core\Exception\Exception
When trying to set a key that is invalid.

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https://api.cakephp.org/3.4/class-Cake.Cache.Engine.NullEngine.html