public function setPrefix($prefix)
    {
        $this->prefix = $prefix;
        $this->identifier = $this->prefix.$this->key;

        return $this;
    }
public function setPrefix($prefix)
    {
        $this->prefix = $prefix;
        $this->identifier = $this->prefix.$this->key;

        return $this;
    }
public function setPrefix ( $ prefix ) { $ this -> prefix = $ prefix ; $ this -> identifier = $ this -> prefix . $ this -> key ; return $ this ; }
Set the prefix

@param  string $prefix
@return $this
Set the prefix