每天laravel-20160630|Repository -1

namespace Illuminate\Cache;

use Closure;
use DateTime;
use ArrayAccess;
use Carbon\Carbon;
use BadMethodCallException;
use Illuminate\Contracts\Cache\Store;
use Illuminate\Support\Traits\Macroable;
use Illuminate\Contracts\Events\Dispatcher;
use Illuminate\Contracts\Cache\Repository as CacheContract;
// a namespace be used enough
class Repository implements CacheContract, ArrayAccess
{// two interface that should be implements by Repository
    use Macroable {
        __call as macroCall;
    }// use Macroable that we will be a __call

    /**
     * The cache store implementation.
     * The cache store
     * @var \Illuminate\Contracts\Cache\Store
     */
    protected $store;// a Cache Store instance of the implementation

    /**
     * The event dispatcher implementation.
     *
     * @var \Illuminate\Contracts\Events\Dispatcher
     */
    protected $events;// The event dispatcher implementation a events interface

    /**
     * The default number of minutes to store items.
     *
     * @var int
     */
    protected $default = 60; // a normal time[minutes]or[seconds] to set the value into the store items .
    // normal set it is 60 second

    /**
     * Create a new cache repository instance.
     *
     * @param  \Illuminate\Contracts\Cache\Store  $store
     * @return void
     */
    public function __construct(Store $store)
    {
        $this->store = $store;
    }// a big __set to Create a new instance about Cache, repository
    // a library to store.

    /**
     * Set the event dispatcher instance.
     *
     * @param  \Illuminate\Contracts\Events\Dispatcher  $events
     * @return void
     */
    public function setEventDispatcher(Dispatcher $events)
    {
        $this->events = $events;
    }// Set the event dispatcher instance.
    // a big set to the events.

    /**
     * Fire an event for this cache instance.
     *
     * @param  string  $event
     * @param  array  $payload
     * @return void
     */
    // Fire an event for this cache instance.
    protected function fireCacheEvent($event, $payload)// fire cache event
    {
        if (! isset($this->events)) {
            return;
        }// check this is a normal events

        switch ($event) {// this->events is a instance about a class, then the events is a way or a type
            case 'hit':// case hit:
                if (count($payload) == 2) {
                    $payload[] = [];
                }

                return $this->events->fire(new Events\CacheHit($payload[0], $payload[1], $payload[2]));
            case 'missed':// case missed:
                if (count($payload) == 1) {
                    $payload[] = [];
                }

                return $this->events->fire(new Events\CacheMissed($payload[0], $payload[1]));
            case 'delete':// case delete:
                if (count($payload) == 1) {
                    $payload[] = [];
                }

                return $this->events->fire(new Events\KeyForgotten($payload[0], $payload[1]));
            case 'write':// cache write:
                if (count($payload) == 3) {
                    $payload[] = [];
                }

                return $this->events->fire(new Events\KeyWritten($payload[0], $payload[1], $payload[2], $payload[3]));
        }
    }// a switch way to change the result

    /**
     * Determine if an item exists in the cache.
     *
     * @param  string  $key
     * @return bool
     */
    public function has($key)
    {
        return ! is_null($this->get($key));
    }// determine[check] the item has exists in the cache.

    /**
     * Retrieve an item from the cache by key. Retrieve an item from the cache by key.
     *
     * @param  string  $key
     * @param  mixed   $default
     * @return mixed
     */
    public function get($key, $default = null)// get item by key.
    {
        if (is_array($key)) {
            return $this->many($key);
        }// the key is a array ,will back a item array by many.

        $value = $this->store->get($this->itemKey($key));// get item[value] by key

        if (is_null($value)) {// null the value
            $this->fireCacheEvent('missed', [$key]);//missed

            $value = value($default);
        } else {
            $this->fireCacheEvent('hit', [$key, $value]);// hit
        }

        return $value;
    }

    /**
     * Retrieve multiple items from the cache by key.// Retrieve multiple items from the cache
     *
     * Items not found in the cache will have a null value.// items not found in the cache will have a null value
     *
     * @param  array  $keys
     * @return array
     */
    public function many(array $keys)
    {
        $normalizedKeys = [];

        foreach ($keys as $key => $value) {
            $normalizedKeys[] = is_string($key) ? $key : $value;
        }

        $values = $this->store->many($normalizedKeys);

        foreach ($values as $key => &$value) {
            if (is_null($value)) {
                $this->fireCacheEvent('missed', [$key]);

                $value = isset($keys[$key]) ? value($keys[$key]) : null;
            } else {
                $this->fireCacheEvent('hit', [$key, $value]);
            }
        }

        return $values;
    }