framework/main/classes/stacker/file/class_BaseFileStack.php

   1 <?php
   2 // Own namespace
   3 namespace CoreFramework\Stack\File;
   4
   5 // Import framework stuff
   6 use CoreFramework\Factory\ObjectFactory;
   7 use CoreFramework\Filesystem\File\BaseBinaryFile;
   8
   9 /**
  10  * A general file-based stack class
  11  *
  12  * @author              Roland Haeder <webmaster@ship-simu.org>
  13  * @version             0.0.0
  14  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  15  * @license             GNU GPL 3.0 or any newer version
  16  * @link                http://www.ship-simu.org
  17  *
  18  * This program is free software: you can redistribute it and/or modify
  19  * it under the terms of the GNU General Public License as published by
  20  * the Free Software Foundation, either version 3 of the License, or
  21  * (at your option) any later version.
  22  *
  23  * This program is distributed in the hope that it will be useful,
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  * GNU General Public License for more details.
  27  *
  28  * You should have received a copy of the GNU General Public License
  29  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  30  */
  31 class BaseFileStack extends BaseStacker {
  32         /**
  33          * Magic for this stack
  34          */
  35         const STACK_MAGIC = 'STACKv0.1';
  36
  37         /**
  38          * Name of array index for gap position
  39          */
  40         const ARRAY_INDEX_GAP_POSITION = 'gap';
  41
  42         /**
  43          * Name of array index for hash
  44          */
  45         const ARRAY_INDEX_HASH = 'hash';
  46
  47         /**
  48          * Name of array index for length of raw data
  49          */
  50         const ARRAY_INDEX_DATA_LENGTH = 'length';
  51
  52         /**
  53          * Protected constructor
  54          *
  55          * @param       $className      Name of the class
  56          * @return      void
  57          */
  58         protected function __construct ($className) {
  59                 // Call parent constructor
  60                 parent::__construct($className);
  61         }
  62
  63         /**
  64          * Reads the file header
  65          *
  66          * @return      void
  67          * @todo        To hard assertions here, better rewrite them to exceptions
  68          */
  69         public function readFileHeader () {
  70                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
  71
  72                 // First rewind to beginning as the header sits at the beginning ...
  73                 $this->getIteratorInstance()->rewind();
  74
  75                 // Then read it (see constructor for calculation)
  76                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
  77                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->getIteratorInstance()->getHeaderSize()));
  78
  79                 // Have all requested bytes been read?
  80                 assert(strlen($data) == $this->getIteratorInstance()->getHeaderSize());
  81                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  82
  83                 // Last character must be the separator
  84                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
  85                 assert(substr($data, -1, 1) == chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES));
  86                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
  87
  88                 // Okay, then remove it
  89                 $data = substr($data, 0, -1);
  90
  91                 // And update seek position
  92                 $this->getIteratorInstance()->updateSeekPosition();
  93
  94                 /*
  95                  * Now split it:
  96                  *
  97                  * 0 => magic
  98                  * 1 => total entries
  99                  * 2 => current seek position
 100                  */
 101                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
 102
 103                 // Set header here
 104                 $this->getIteratorInstance()->setHeader($header);
 105
 106                 // Check if the array has only 3 elements
 107                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($header), print_r($header, TRUE)));
 108                 assert(count($header) == 3);
 109                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 110
 111                 // Check magic
 112                 assert($header[0] == self::STACK_MAGIC);
 113                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 114
 115                 // Check length of count and seek position
 116                 assert(strlen($header[1]) == BaseBinaryFile::LENGTH_COUNT);
 117                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 118                 assert(strlen($header[2]) == BaseBinaryFile::LENGTH_POSITION);
 119                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 120
 121                 // Decode count and seek position
 122                 $header[1] = hex2bin($header[1]);
 123                 $header[2] = hex2bin($header[2]);
 124
 125                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 126         }
 127
 128         /**
 129          * Flushes the file header
 130          *
 131          * @return      void
 132          */
 133         public function flushFileHeader () {
 134                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 135
 136                 // Put all informations together
 137                 $header = sprintf('%s%s%s%s%s%s',
 138                         // Magic
 139                         self::STACK_MAGIC,
 140
 141                         // Separator magic<->count
 142                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 143
 144                         // Total entries (will be zero) and pad it to 20 chars
 145                         str_pad($this->dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 146
 147                         // Separator count<->seek position
 148                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 149
 150                         // Position (will be zero)
 151                         str_pad($this->dec2hex($this->getIteratorInstance()->getSeekPosition(), 2), BaseBinaryFile::LENGTH_POSITION, '0', STR_PAD_LEFT),
 152
 153                         // Separator position<->entries
 154                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 155                 );
 156
 157                 // Write it to disk (header is always at seek position 0)
 158                 $this->getIteratorInstance()->writeData(0, $header, FALSE);
 159
 160                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
 161         }
 162
 163         /**
 164          * Initializes this file-based stack.
 165          *
 166          * @param       $fileName       File name of this stack
 167          * @param       $type           Type of this stack (e.g. url_source for URL sources)
 168          * @return      void
 169          * @todo        Currently the stack file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole stack file.
 170          */
 171         protected function initFileStack ($fileName, $type) {
 172                 // Get a stack file instance
 173                 $fileInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileName, $this));
 174
 175                 // Get iterator instance
 176                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 177
 178                 // Is the instance implementing the right interface?
 179                 assert($iteratorInstance instanceof SeekableWritableFileIterator);
 180
 181                 // Set iterator here
 182                 $this->setIteratorInstance($iteratorInstance);
 183
 184                 // Calculate header size
 185                 $this->getIteratorInstance()->setHeaderSize(
 186                         strlen(self::STACK_MAGIC) +
 187                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 188                         BaseBinaryFile::LENGTH_COUNT +
 189                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 190                         BaseBinaryFile::LENGTH_POSITION +
 191                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 192                 );
 193
 194                 // Init counters and gaps array
 195                 $this->getIteratorInstance()->initCountersGapsArray();
 196
 197                 // Is the file's header initialized?
 198                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 199                         // No, then create it (which may pre-allocate the stack)
 200                         $this->getIteratorInstance()->createFileHeader();
 201
 202                         // And pre-allocate a bit
 203                         $this->getIteratorInstance()->preAllocateFile('file_stack');
 204                 } // END - if
 205
 206                 // Load the file header
 207                 $this->readFileHeader();
 208
 209                 // Count all entries in file
 210                 $this->getIteratorInstance()->analyzeFile();
 211
 212                 /*
 213                  * Get stack index instance. This can be used for faster
 214                  * "defragmentation" and startup.
 215                  */
 216                 $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileName, $type);
 217
 218                 // And set it here
 219                 $this->setIndexInstance($indexInstance);
 220         }
 221
 222         /**
 223          * Adds a value to given stack
 224          *
 225          * @param       $stackerName    Name of the stack
 226          * @param       $value                  Value to add to this stacker
 227          * @return      void
 228          * @throws      FullStackerException    If the stack is full
 229          */
 230         protected function addValue ($stackerName, $value) {
 231                 // Do some tests
 232                 if ($this->isStackFull($stackerName)) {
 233                         // Stacker is full
 234                         throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
 235                 } // END - if
 236
 237                 // Debug message
 238                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName . ',value[' . gettype($value) . ']=' . print_r($value, TRUE));
 239
 240                 // No objects/resources are allowed as their serialization takes to long
 241                 assert(!is_object($value));
 242                 assert(!is_resource($value));
 243
 244                 /*
 245                  * Now add the value to the file stack which returns gap position, a
 246                  * hash and length of the raw data.
 247                  */
 248                 $data = $this->getIteratorInstance()->writeValueToFile($stackerName, $value);
 249
 250                 // Add the hash and gap position to the index
 251                 $this->getIndexInstance()->addHashToIndex($stackerName, $data);
 252         }
 253
 254         /**
 255          * Get last value from named stacker
 256          *
 257          * @param       $stackerName    Name of the stack
 258          * @return      $value                  Value of last added value
 259          * @throws      EmptyStackerException   If the stack is empty
 260          */
 261         protected function getLastValue ($stackerName) {
 262                 // Is the stack not yet initialized or full?
 263                 if ($this->isStackEmpty($stackerName)) {
 264                         // Throw an exception
 265                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 266                 } // END - if
 267
 268                 // Now get the last value
 269                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 270                 $value = NULL;
 271
 272                 // Return it
 273                 return $value;
 274         }
 275
 276         /**
 277          * Get first value from named stacker
 278          *
 279          * @param       $stackerName    Name of the stack
 280          * @return      $value                  Value of last added value
 281          * @throws      EmptyStackerException   If the stack is empty
 282          */
 283         protected function getFirstValue ($stackerName) {
 284                 // Is the stack not yet initialized or full?
 285                 if ($this->isStackEmpty($stackerName)) {
 286                         // Throw an exception
 287                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 288                 } // END - if
 289
 290                 // Now get the first value
 291                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 292                 $value = NULL;
 293
 294                 // Return it
 295                 return $value;
 296         }
 297
 298         /**
 299          * "Pops" last entry from stack
 300          *
 301          * @param       $stackerName    Name of the stack
 302          * @return      $value                  Value "poped" from array
 303          * @throws      EmptyStackerException   If the stack is empty
 304          */
 305         protected function popLast ($stackerName) {
 306                 // Is the stack not yet initialized or full?
 307                 if ($this->isStackEmpty($stackerName)) {
 308                         // Throw an exception
 309                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 310                 } // END - if
 311
 312                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 313                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 314                 return NULL;
 315         }
 316
 317         /**
 318          * "Pops" first entry from stack
 319          *
 320          * @param       $stackerName    Name of the stack
 321          * @return      $value                  Value "shifted" from array
 322          * @throws      EmptyStackerException   If the named stacker is empty
 323          */
 324         protected function popFirst ($stackerName) {
 325                 // Is the stack not yet initialized or full?
 326                 if ($this->isStackEmpty($stackerName)) {
 327                         // Throw an exception
 328                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 329                 } // END - if
 330
 331                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 332                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 333                 return NULL;
 334         }
 335
 336         /**
 337          * Checks whether the given stack is full
 338          *
 339          * @param       $stackerName    Name of the stack
 340          * @return      $isFull                 Whether the stack is full
 341          */
 342         protected function isStackFull ($stackerName) {
 343                 // File-based stacks will only run full if the disk space is low.
 344                 // @TODO Please implement this, returning FALSE
 345                 $isFull = FALSE;
 346
 347                 // Return result
 348                 return $isFull;
 349         }
 350
 351         /**
 352          * Checks whether the given stack is empty
 353          *
 354          * @param       $stackerName            Name of the stack
 355          * @return      $isEmpty                        Whether the stack is empty
 356          * @throws      NoStackerException      If given stack is missing
 357          */
 358         public function isStackEmpty ($stackerName) {
 359                 // So, is the stack empty?
 360                 $isEmpty = (($this->getStackCount($stackerName)) == 0);
 361
 362                 // Return result
 363                 return $isEmpty;
 364         }
 365
 366         /**
 367          * Initializes given stacker
 368          *
 369          * @param       $stackerName    Name of the stack
 370          * @param       $forceReInit    Force re-initialization
 371          * @return      void
 372          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 373          */
 374         public function initStack ($stackerName, $forceReInit = FALSE) {
 375                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 376         }
 377
 378         /**
 379          * Initializes all stacks
 380          *
 381          * @return      void
 382          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 383          */
 384         public function initStacks (array $stacks, $forceReInit = FALSE) {
 385                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 386         }
 387
 388         /**
 389          * Checks whether the given stack is initialized (set in array $stackers)
 390          *
 391          * @param       $stackerName    Name of the stack
 392          * @return      $isInitialized  Whether the stack is initialized
 393          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 394          */
 395         public function isStackInitialized ($stackerName) {
 396                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 397         }
 398
 399         /**
 400          * Determines whether the EOF has been reached
 401          *
 402          * @return      $isEndOfFileReached             Whether the EOF has been reached
 403          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 404          */
 405         public function isEndOfFileReached () {
 406                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 407         }
 408
 409         /**
 410          * Getter for file name
 411          *
 412          * @return      $fileName       The current file name
 413          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 414          */
 415         public function getFileName () {
 416                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 417         }
 418
 419         /**
 420          * Getter for size of given stack (array count)
 421          *
 422          * @param       $stackerName    Name of the stack
 423          * @return      $count                  Size of stack (array count)
 424          */
 425         public function getStackCount ($stackerName) {
 426                 // Now, simply return the found count value, this must be up-to-date then!
 427                 return $this->getIteratorInstance()->getCounter();
 428         }
 429
 430         /**
 431          * Calculates minimum length for one entry/block
 432          *
 433          * @return      $length         Minimum length for one entry/block
 434          */
 435         public function calculateMinimumBlockLength () {
 436                 // Calulcate it
 437                 $length =
 438                         // Length of entry group
 439                         BaseBinaryFile::LENGTH_GROUP + strlen(chr(BaseBinaryFile::SEPARATOR_GROUP_HASH)) +
 440                         // Hash + value
 441                         self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
 442                         // Final separator
 443                         strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 444
 445                 // Return it
 446                 return $length;
 447         }
 448
 449         /**
 450          * Initializes counter for valid entries, arrays for damaged entries and
 451          * an array for gap seek positions. If you call this method on your own,
 452          * please re-analyze the file structure. So you are better to call
 453          * analyzeFile() instead of this method.
 454          *
 455          * @return      void
 456          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 457          */
 458         public function initCountersGapsArray () {
 459                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 460         }
 461
 462         /**
 463          * Getter for header size
 464          *
 465          * @return      $totalEntries   Size of file header
 466          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 467          */
 468         public final function getHeaderSize () {
 469                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 470         }
 471
 472         /**
 473          * Setter for header size
 474          *
 475          * @param       $headerSize             Size of file header
 476          * @return      void
 477          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 478          */
 479         public final function setHeaderSize ($headerSize) {
 480                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 481         }
 482
 483         /**
 484          * Getter for header array
 485          *
 486          * @return      $totalEntries   Size of file header
 487          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 488          */
 489         public final function getHeader () {
 490                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 491         }
 492
 493         /**
 494          * Setter for header
 495          *
 496          * @param       $header         Array for a file header
 497          * @return      void
 498          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 499          */
 500         public final function setHeader (array $header) {
 501                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 502         }
 503
 504         /**
 505          * Updates seekPosition attribute from file to avoid to much access on file.
 506          *
 507          * @return      void
 508          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 509          */
 510         public function updateSeekPosition () {
 511                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 512         }
 513
 514         /**
 515          * Getter for total entries
 516          *
 517          * @return      $totalEntries   Total entries in this file
 518          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 519          */
 520         public final function getCounter () {
 521                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 522         }
 523
 524         /**
 525          * Writes data at given position
 526          *
 527          * @param       $seekPosition   Seek position
 528          * @param       $data                   Data to be written
 529          * @param       $flushHeader    Whether to flush the header (default: flush)
 530          * @return      void
 531          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 532          */
 533         public function writeData ($seekPosition, $data, $flushHeader = TRUE) {
 534                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data[]=%s,flushHeader=%d', __METHOD__, __LINE__, $seekPosition, gettype($data), intval($flushHeader)));
 535                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 536         }
 537
 538         /**
 539          * Writes given value to the file and returns a hash and gap position for it
 540          *
 541          * @param       $groupId        Group identifier
 542          * @param       $value          Value to be added to the stack
 543          * @return      $data           Hash and gap position
 544          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 545          */
 546         public function writeValueToFile ($groupId, $value) {
 547                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,value[%s]=%s', __METHOD__, __LINE__, $groupId, gettype($value), print_r($value, TRUE)));
 548                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 549         }
 550
 551         /**
 552          * Searches for next suitable gap the given length of data can fit in
 553          * including padding bytes.
 554          *
 555          * @param       $length                 Length of raw data
 556          * @return      $seekPosition   Found next gap's seek position
 557          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 558          */
 559         public function searchNextGap ($length) {
 560                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] length=%s', __METHOD__, __LINE__, $length));
 561                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 562         }
 563
 564         /**
 565          * "Getter" for file size
 566          *
 567          * @return      $fileSize       Size of currently loaded file
 568          */
 569         public function getFileSize () {
 570                 // Call iterator's method
 571                 return $this->getIteratorInstance()->getFileSize();
 572         }
 573
 574         /**
 575          * Writes given raw data to the file and returns a gap position and length
 576          *
 577          * @param       $groupId        Group identifier
 578          * @param       $hash           Hash from encoded value
 579          * @param       $encoded        Encoded value to be written to the file
 580          * @return      $data           Gap position and length of the raw data
 581          */
 582         public function writeDataToFreeGap ($groupId, $hash, $encoded) {
 583                 // Debug message
 584                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,encoded()=%d - CALLED!', __METHOD__, __LINE__, $groupId, $hash, strlen($encoded)));
 585
 586                 // Raw data been written to the file
 587                 $rawData = sprintf('%s%s%s%s%s',
 588                         $groupId,
 589                         BaseBinaryFile::SEPARATOR_GROUP_HASH,
 590                         hex2bin($hash),
 591                         BaseBinaryFile::SEPARATOR_HASH_VALUE,
 592                         $encoded
 593                 );
 594
 595                 // Debug message
 596                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d', __METHOD__, __LINE__, $groupId, $hash, strlen($rawData)));
 597
 598                 // Search for next free gap
 599                 $gapPosition = $this->getIteratorInstance()->searchNextGap(strlen($rawData));
 600
 601                 // Gap position cannot be smaller than header length + 1
 602                 assert($gapPosition > $this->getIteratorInstance()->getHeaderSize());
 603
 604                 // Debug message
 605                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,gapPosition=%s', __METHOD__, __LINE__, $groupId, $hash, $gapPosition));
 606
 607                 // Then write the data at that gap
 608                 $this->getIteratorInstance()->writeData($gapPosition, $rawData);
 609
 610                 // Debug message
 611                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('[%s:%d:] groupId=%s,hash=%s,rawData()=%d - EXIT!', __METHOD__, __LINE__, $groupId, $hash, strlen($rawData)));
 612
 613                 // Return gap position, hash and length of raw data
 614                 return array(
 615                         self::ARRAY_INDEX_GAP_POSITION => $gapPosition,
 616                         self::ARRAY_INDEX_HASH         => $hash,
 617                         self::ARRAY_INDEX_DATA_LENGTH  => strlen($rawData)
 618                 );
 619         }
 620
 621 }