public function initializeDictionaryFiles()
    {
        $this->_tisFile = $this->_directory->createFile($this->_name . '.tis');
        $this->_tisFile->writeInt((int)0xFFFFFFFD);
        $this->_tisFile->writeLong(0 /* dummy data for terms count */);
        $this->_tisFile->writeInt(self::$indexInterval);
        $this->_tisFile->writeInt(self::$skipInterval);
        $this->_tisFile->writeInt(self::$maxSkipLevels);

        $this->_tiiFile = $this->_directory->createFile($this->_name . '.tii');
        $this->_tiiFile->writeInt((int)0xFFFFFFFD);
        $this->_tiiFile->writeLong(0 /* dummy data for terms count */);
        $this->_tiiFile->writeInt(self::$indexInterval);
        $this->_tiiFile->writeInt(self::$skipInterval);
        $this->_tiiFile->writeInt(self::$maxSkipLevels);

        /**
 * Dump dictionary header 
*/
        $this->_tiiFile->writeVInt(0);                    // preffix length
        $this->_tiiFile->writeString('');                 // suffix
        $this->_tiiFile->writeInt((int)0xFFFFFFFF);       // field number
        $this->_tiiFile->writeByte((int)0x0F);
        $this->_tiiFile->writeVInt(0);                    // DocFreq
        $this->_tiiFile->writeVInt(0);                    // FreqDelta
        $this->_tiiFile->writeVInt(0);                    // ProxDelta
        $this->_tiiFile->writeVInt(24);                   // IndexDelta

        $this->_frqFile = $this->_directory->createFile($this->_name . '.frq');
        $this->_prxFile = $this->_directory->createFile($this->_name . '.prx');

        $this->_files[] = $this->_name . '.tis';
        $this->_files[] = $this->_name . '.tii';
        $this->_files[] = $this->_name . '.frq';
        $this->_files[] = $this->_name . '.prx';

        $this->_prevTerm          = null;
        $this->_prevTermInfo      = null;
        $this->_prevIndexTerm     = null;
        $this->_prevIndexTermInfo = null;
        $this->_lastIndexPosition = 24;
        $this->_termCount         = 0;

    }