PHP RedisSingleton

<?php

/**
 * Created by PhpStorm.
 * User: xiongzai
 * Date: 2016/5/17
 * Time: 16:31
 */

namespace Think;

class RedisSingleton {

    public $redis = null;

    static protected $ins=null;

    final protected function __construct(){
        self::setRedis();
    }

    private function __clone(){}

    static public function getInstance(){
        if (self::$ins instanceof self) {
            return self::$ins;
        }
        self::$ins=new self();
        return self::$ins;
    }


     private function setRedis(){
        try{
            $redis = new \Redis();
            $redis->connect( C('REDIS_HOST'), C('REDIS_PORT') );
            $redis->auth( C('REDIS_AUTH') );
            $this->redis = $redis;
            unset($redis);
        }catch(Exception $e){
            echo $e->getMessage().'
';
        }
    }

}