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                <?php  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                namespace SilverStripe\HybridSessions;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use SessionHandlerInterface;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use SilverStripe\Core\Injector\Injector;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use SilverStripe\HybridSessions\Store\BaseStore;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                class HybridSession extends BaseStore  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * List of session handlers  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected $handlers = [];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * True if this session store has been initialised  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var bool  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected static $enabled = false;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param SessionHandlerInterface[]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return $this  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function setHandlers($handlers)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->handlers = $handlers;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->setKey($this->getKey());  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return $this;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return $this  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function setKey($key)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        parent::setKey($key);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        foreach ($this->getHandlers() as $handler) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $handler->setKey($key);  | 
            
                            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return $this;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return SessionHandlerInterface[]  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
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                     */  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    public function getHandlers()  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    { | 
            
            
                                                                        
                            
            
                                    
            
            
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                        return $this->handlers ?: [];  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $save_path  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $name  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return bool  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function open($save_path, $name)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        foreach ($this->getHandlers() as $handler) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $handler->open($save_path, $name);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return true;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return bool  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function close()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        foreach ($this->getHandlers() as $handler) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $handler->close();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return true;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $session_id  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return string  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function read($session_id)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        foreach ($this->getHandlers() as $handler) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            if ($data = $handler->read($session_id)) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                return $data;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return '';  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function write($session_id, $session_data)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        foreach ($this->getHandlers() as $handler) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            if ($handler->write($session_id, $session_data)) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                return true;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return false;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function destroy($session_id)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        foreach ($this->getHandlers() as $handler) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $handler->destroy($session_id);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return true;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function gc($maxlifetime)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        foreach ($this->getHandlers() as $handler) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $handler->gc($maxlifetime);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Register the session handler as the default  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $key Desired session key  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public static function init($key = null)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $instance = Injector::inst()->get(__CLASS__);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                | 
                    142
                 | 
                                    
                                                     | 
                
                 | 
                        if (empty($key)) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    143
                 | 
                                    
                                                     | 
                
                 | 
                            user_error(  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    144
                 | 
                                    
                                                     | 
                
                 | 
                                'HybridSession::init() was not given a $key. Disabling cookie-based storage',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    145
                 | 
                                    
                                                     | 
                
                 | 
                                E_USER_WARNING  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    146
                 | 
                                    
                                                     | 
                
                 | 
                            );  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    147
                 | 
                                    
                                                     | 
                
                 | 
                        } else { | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    148
                 | 
                                    
                                                     | 
                
                 | 
                            $instance->setKey($key);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    149
                 | 
                                    
                                                     | 
                
                 | 
                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    150
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    151
                 | 
                                    
                                                     | 
                
                 | 
                        session_set_save_handler($instance, true);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    152
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    153
                 | 
                                    
                                                     | 
                
                 | 
                        self::$enabled = true;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    154
                 | 
                                    
                                                     | 
                
                 | 
                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    155
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    156
                 | 
                                    
                                                     | 
                
                 | 
                    public static function is_enabled()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    157
                 | 
                                    
                                                     | 
                
                 | 
                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    158
                 | 
                                    
                                                     | 
                
                 | 
                        return self::$enabled;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    159
                 | 
                                    
                                                     | 
                
                 | 
                    }  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
                | 
                    160
                 | 
                                    
                                                     | 
                
                 | 
                }  | 
            
            
                                                        
            
                                    
            
            
                | 
                    161
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                        
Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different implementation of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the interface: