]> git.mxchange.org Git - core.git/blobdiff - framework/main/classes/stacker/file/class_BaseFileStack.php
Continued:
[core.git] / framework / main / classes / stacker / file / class_BaseFileStack.php
index 6c1f3d1cfabfc3bbf4325dbd956af6d82aa1af24..30f20f9c93fcc9c39e8564bfc6844155d979e65c 100644 (file)
@@ -1,19 +1,22 @@
 <?php
 // Own namespace
-namespace Org\Mxchange\CoreFramework\Stacker\Filesystem;
+namespace Org\Mxchange\CoreFramework\Stack\File;
 
 // Import framework stuff
-use Org\Mxchange\CoreFramework\Factory\Filesystem\Stack\FileStackIndexFactory;
+use Org\Mxchange\CoreFramework\Factory\Stack\File\FileStackIndexFactory;
 use Org\Mxchange\CoreFramework\Factory\ObjectFactory;
-use Org\Mxchange\CoreFramework\FileStack\InvalidMagicException;
 use Org\Mxchange\CoreFramework\Filesystem\File\BaseBinaryFile;
 use Org\Mxchange\CoreFramework\Generic\UnsupportedOperationException;
-use Org\Mxchange\CoreFramework\Index\Indexable;
 use Org\Mxchange\CoreFramework\Iterator\Filesystem\SeekableWritableFileIterator;
-use Org\Mxchange\CoreFramework\Stacker\BaseStacker;
+use Org\Mxchange\CoreFramework\Stack\BaseStacker;
+use Org\Mxchange\CoreFramework\Stack\File\InvalidMagicException;
+use Org\Mxchange\CoreFramework\Stack\File\StackableFile;
+use Org\Mxchange\CoreFramework\Traits\Index\IndexableTrait;
+use Org\Mxchange\CoreFramework\Traits\Iterator\IteratorTrait;
 use Org\Mxchange\CoreFramework\Utils\String\StringUtils;
 
 // Import SPL stuff
+use \InvalidArgumentException;
 use \SplFileInfo;
 use \UnexpectedValueException;
 
@@ -39,34 +42,18 @@ use \UnexpectedValueException;
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-abstract class BaseFileStack extends BaseStacker {
+abstract class BaseFileStack extends BaseStacker implements StackableFile {
+       // Load traits
+       use IndexableTrait;
+       use IteratorTrait;
+
        // Exception codes
        const EXCEPTION_BAD_MAGIC = 0xe100;
 
        /**
-        * Magic for this stack
-        */
-       const STACK_MAGIC = 'STACKv0.1';
-
-       /**
-        * Name of array index for gap position
-        */
-       const ARRAY_INDEX_GAP_POSITION = 'gap';
-
-       /**
-        * Name of array index for hash
+        * Minimum block length
         */
-       const ARRAY_INDEX_HASH = 'hash';
-
-       /**
-        * Name of array index for length of raw data
-        */
-       const ARRAY_INDEX_DATA_LENGTH = 'length';
-
-       /**
-        * An instance of an Indexable class
-        */
-       private $indexInstance = NULL;
+       private static $minimumBlockLength = 0;
 
        /**
         * Protected constructor
@@ -79,25 +66,6 @@ abstract class BaseFileStack extends BaseStacker {
                parent::__construct($className);
        }
 
-       /**
-        * Setter for Indexable instance
-        *
-        * @param       $indexInstance  An instance of an Indexable class
-        * @return      void
-        */
-       protected final function setIndexInstance (Indexable $indexInstance) {
-               $this->indexInstance = $indexInstance;
-       }
-
-       /**
-        * Getter for Indexable instance
-        *
-        * @return      $indexInstance  An instance of an Indexable class
-        */
-       public final function getIndexInstance () {
-               return $this->indexInstance;
-       }
-
        /**
         * Reads the file header
         *
@@ -108,7 +76,7 @@ abstract class BaseFileStack extends BaseStacker {
         */
        public function readFileHeader () {
                // First rewind to beginning as the header sits at the beginning ...
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: CALLED!', __METHOD__, __LINE__));
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
                $this->getIteratorInstance()->rewind();
 
                // Then read it (see constructor for calculation)
@@ -150,9 +118,6 @@ abstract class BaseFileStack extends BaseStacker {
                 */
                $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
 
-               // Set header here
-               $this->getIteratorInstance()->setHeader($header);
-
                // Check if the array has only 3 elements
                /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: header(%d)=%s', count($header), print_r($header, true)));
                if (count($header) != 3) {
@@ -161,7 +126,7 @@ abstract class BaseFileStack extends BaseStacker {
                                $data,
                                count($header)
                        ));
-               } elseif ($header[0] != self::STACK_MAGIC) {
+               } elseif ($header[0] != StackableFile::STACK_MAGIC) {
                        // Bad magic
                        throw new InvalidMagicException($data, self::EXCEPTION_BAD_MAGIC);
                }
@@ -187,6 +152,9 @@ abstract class BaseFileStack extends BaseStacker {
                $header[1] = hex2bin($header[1]);
                $header[2] = hex2bin($header[2]);
 
+               // Set header here
+               $this->getIteratorInstance()->setHeader($header);
+
                // Trace message
                /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: EXIT!', __METHOD__, __LINE__));
        }
@@ -198,10 +166,10 @@ abstract class BaseFileStack extends BaseStacker {
         */
        public function flushFileHeader () {
                // Put all informations together
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: CALLED!', __METHOD__, __LINE__));
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
                $header = sprintf('%s%s%s%s%s%s',
                        // Magic
-                       self::STACK_MAGIC,
+                       StackableFile::STACK_MAGIC,
 
                        // Separator magic<->count
                        chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
@@ -223,7 +191,7 @@ abstract class BaseFileStack extends BaseStacker {
                $this->getIteratorInstance()->writeData(0, $header, false);
 
                // Trace message
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: EXIT!', __METHOD__, __LINE__));
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: EXIT!');
        }
 
        /**
@@ -232,24 +200,29 @@ abstract class BaseFileStack extends BaseStacker {
         * @param       $fileInfoInstance       An instance of a SplFileInfo class
         * @param       $type           Type of this stack (e.g. url_source for URL sources)
         * @return      void
+        * @throws      InvalidArgumentException        If a parameter is invalid
         * @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.
         */
        protected function initFileStack (SplFileInfo $fileInfoInstance, string $type) {
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: fileInfoInstance[%s]=%s,type=%s - CALLED!', get_class($fileInfoInstance), $fileInfoInstance, $type));
+               if (empty($type)) {
+                       // Invalid parameter
+                       throw new InvalidArgumentException('Parameter "type" is empty');
+               }
+
                // Get a stack file instance
-               $fileInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileInfoInstance, $this));
+               $stackInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileInfoInstance, $this));
 
                // Get iterator instance
-               $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
-
-               // Is the instance implementing the right interface?
-               assert($iteratorInstance instanceof SeekableWritableFileIterator);
+               $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($stackInstance));
 
                // Set iterator here
                $this->setIteratorInstance($iteratorInstance);
 
                // Calculate header size
                $this->getIteratorInstance()->setHeaderSize(
-                       strlen(self::STACK_MAGIC) +
+                       strlen(StackableFile::STACK_MAGIC) +
                        strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
                        BaseBinaryFile::LENGTH_COUNT +
                        strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
@@ -267,7 +240,7 @@ abstract class BaseFileStack extends BaseStacker {
 
                        // And pre-allocate a bit
                        $this->getIteratorInstance()->preAllocateFile('file_stack');
-               } // END - if
+               }
 
                // Load the file header
                $this->readFileHeader();
@@ -283,6 +256,9 @@ abstract class BaseFileStack extends BaseStacker {
 
                // And set it here
                $this->setIndexInstance($indexInstance);
+
+               // Trace message
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: EXIT!');
        }
 
        /**
@@ -292,18 +268,22 @@ abstract class BaseFileStack extends BaseStacker {
         * @param       $value                  Value to add to this stacker
         * @return      void
         * @throws      FullStackerException    If the stack is full
+        * @throws      InvalidArgumentException        If a parameter is not valid
+        * @throws      InvalidArgumentException        Not all variable types are wanted here
         */
        protected function addValue (string $stackerName, $value) {
-               // Do some tests
-               if ($this->isStackFull($stackerName)) {
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s,value[%s]=%s - CALLED!', $stackerName, gettype($value), print_r($value, true)));
+               if (empty($stackerName)) {
+                       // No empty stack name
+                       throw new InvalidArgumentException('Parameter "stackerName" is empty');
+               } elseif ($this->isStackFull($stackerName)) {
                        // Stacker is full
                        throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
-               } // END - if
-
-               // No objects/resources are allowed as their serialization takes to long
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName . ',value[' . gettype($value) . ']=' . print_r($value, true));
-               assert(!is_object($value));
-               assert(!is_resource($value));
+               } elseif (is_resource($value) || is_object($value)) {
+                       // Not wanted type
+                       throw new InvalidArgumentException(sprintf('value[]=%s is not supported', gettype($value)));
+               }
 
                /*
                 * Now add the value to the file stack which returns gap position, a
@@ -313,6 +293,9 @@ abstract class BaseFileStack extends BaseStacker {
 
                // Add the hash and gap position to the index
                $this->getIndexInstance()->addHashToIndex($stackerName, $data);
+
+               // Trace message
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: EXIT!');
        }
 
        /**
@@ -320,20 +303,26 @@ abstract class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value of last added value
-        * @throws      EmptyStackerException   If the stack is empty
+        * @throws      InvalidArgumentException        If a parameter is not valid
+        * @throws      BadMethodCallException  If the stack is empty
         */
        protected function getLastValue (string $stackerName) {
-               // Is the stack not yet initialized or full?
-               if ($this->isStackEmpty($stackerName)) {
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
+               if (empty($stackerName)) {
+                       // No empty stack name
+                       throw new InvalidArgumentException('Parameter "stackerName" is empty');
+               } elseif ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
-                       throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               } // END - if
+                       throw new BadMethodCallException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
+               }
 
                // Now get the last value
                /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
                $value = NULL;
 
                // Return it
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: value[]=%s - EXIT!', gettype($value)));
                return $value;
        }
 
@@ -342,20 +331,26 @@ abstract class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value of last added value
-        * @throws      EmptyStackerException   If the stack is empty
+        * @throws      InvalidArgumentException        If a parameter is not valid
+        * @throws      BadMethodCallException  If the stack is empty
         */
        protected function getFirstValue (string $stackerName) {
-               // Is the stack not yet initialized or full?
-               if ($this->isStackEmpty($stackerName)) {
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
+               if (empty($stackerName)) {
+                       // No empty stack name
+                       throw new InvalidArgumentException('Parameter "stackerName" is empty');
+               } elseif ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
-                       throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               } // END - if
+                       throw new BadMethodCallException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
+               }
 
                // Now get the first value
                /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
                $value = NULL;
 
                // Return it
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: value[]=%s - EXIT!', gettype($value)));
                return $value;
        }
 
@@ -364,14 +359,19 @@ abstract class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value "poped" from array
-        * @throws      EmptyStackerException   If the stack is empty
+        * @throws      InvalidArgumentException        If a parameter is not valid
+        * @throws      BadMethodCallException  If the stack is empty
         */
        protected function popLast (string $stackerName) {
-               // Is the stack not yet initialized or full?
-               if ($this->isStackEmpty($stackerName)) {
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
+               if (empty($stackerName)) {
+                       // No empty stack name
+                       throw new InvalidArgumentException('Parameter "stackerName" is empty');
+               } elseif ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
-                       throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               } // END - if
+                       throw new BadMethodCallException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
+               }
 
                // Now, remove the last entry, we don't care about the return value here, see elseif() block above
                /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
@@ -383,14 +383,19 @@ abstract class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value "shifted" from array
-        * @throws      EmptyStackerException   If the named stacker is empty
+        * @throws      InvalidArgumentException        If a parameter is not valid
+        * @throws      BadMethodCallException  If the named stacker is empty
         */
        protected function popFirst (string $stackerName) {
-               // Is the stack not yet initialized or full?
-               if ($this->isStackEmpty($stackerName)) {
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
+               if (empty($stackerName)) {
+                       // No empty stack name
+                       throw new InvalidArgumentException('Parameter "stackerName" is empty');
+               } elseif ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
-                       throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               } // END - if
+                       throw new BadMethodCallException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
+               }
 
                // Now, remove the last entry, we don't care about the return value here, see elseif() block above
                /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
@@ -402,13 +407,22 @@ abstract class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $isFull                 Whether the stack is full
+        * @throws      InvalidArgumentException        If a parameter is not valid
         */
        protected function isStackFull (string $stackerName) {
-               // File-based stacks will only run full if the disk space is low.
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
+               if (empty($stackerName)) {
+                       // No empty stack name
+                       throw new InvalidArgumentException('Parameter "stackerName" is empty');
+               }
+
                // @TODO Please implement this, returning false
+               /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
                $isFull = false;
 
                // Return result
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: isFull=%d - EXIT!', intval($isFull)));
                return $isFull;
        }
 
@@ -417,13 +431,22 @@ abstract class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName            Name of the stack
         * @return      $isEmpty                        Whether the stack is empty
-        * @throws      NoStackerException      If given stack is missing
+        * @throws      InvalidArgumentException        If a parameter is not valid
+        * @throws      BadMethodCallException  If given stack is missing
         */
        public function isStackEmpty (string $stackerName) {
+               // Validate parameter
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
+               if (empty($stackerName)) {
+                       // No empty stack name
+                       throw new InvalidArgumentException('Parameter "stackerName" is empty');
+               }
+
                // So, is the stack empty?
                $isEmpty = (($this->getStackCount($stackerName)) == 0);
 
                // Return result
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: isEmpty=%d - EXIT!', intval($isEmpty)));
                return $isEmpty;
        }
 
@@ -478,7 +501,12 @@ abstract class BaseFileStack extends BaseStacker {
         */
        public function getStackCount (string $stackerName) {
                // Now, simply return the found count value, this must be up-to-date then!
-               return $this->getIteratorInstance()->getCounter();
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
+               $count = $this->getIteratorInstance()->getCounter();
+
+               // Return count
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: count=%d - EXIT!', $count));
+               return $count;
        }
 
        /**
@@ -487,17 +515,22 @@ abstract class BaseFileStack extends BaseStacker {
         * @return      $length         Minimum length for one entry/block
         */
        public function calculateMinimumBlockLength () {
-               // Calulcate it
-               $length =
-                       // Length of entry group
-                       BaseBinaryFile::LENGTH_GROUP + strlen(chr(BaseBinaryFile::SEPARATOR_GROUP_HASH)) +
-                       // Hash + value
-                       self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
-                       // Final separator
-                       strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
+               // Is the value "cached"?
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
+               if (self::$minimumBlockLength == 0) {
+                       // Calulcate it
+                       self::$minimumBlockLength =
+                               // Length of entry group
+                               BaseBinaryFile::LENGTH_GROUP + strlen(chr(BaseBinaryFile::SEPARATOR_GROUP_HASH)) +
+                               // Hash + value
+                               self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
+                               // Final separator
+                               strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
+               }
 
                // Return it
-               return $length;
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: self::minimumBlockLength=%d - EXIT!', self::$minimumBlockLength));
+               return self::$minimumBlockLength;
        }
 
        /**
@@ -584,7 +617,7 @@ abstract class BaseFileStack extends BaseStacker {
         * @return      void
         * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
         */
-       public function writeData ($seekPosition, $data, bool $flushHeader = true) {
+       public function writeData (int $seekPosition, string $data, bool $flushHeader = true) {
                /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: seekPosition=%s,data[]=%s,flushHeader=%d', $seekPosition, gettype($data), intval($flushHeader)));
                throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
        }
@@ -597,7 +630,7 @@ abstract class BaseFileStack extends BaseStacker {
         * @return      $data           Hash and gap position
         * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
         */
-       public function writeValueToFile ($groupId, $value) {
+       public function writeValueToFile (string $groupId, $value) {
                /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,value[%s]=%s', $groupId, gettype($value), print_r($value, true)));
                throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
        }
@@ -611,7 +644,8 @@ abstract class BaseFileStack extends BaseStacker {
         * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
         */
        public function searchNextGap (int $length) {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: length=%s', $length));
+               // Not supported here
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: length=%d - CALLED!', $length));
                throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
        }
 
@@ -622,7 +656,12 @@ abstract class BaseFileStack extends BaseStacker {
         */
        public function getFileSize () {
                // Call iterator's method
-               return $this->getIteratorInstance()->getFileSize();
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
+               $size = $this->getIteratorInstance()->getFileSize();
+
+               // Return size
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: size=%d - EXIT!', $size));
+               return $size;
        }
 
        /**
@@ -633,7 +672,7 @@ abstract class BaseFileStack extends BaseStacker {
         * @param       $encoded        Encoded value to be written to the file
         * @return      $data           Gap position and length of the raw data
         */
-       public function writeDataToFreeGap ($groupId, string $hash, $encoded) {
+       public function writeDataToFreeGap (string $groupId, string $hash, string $encoded) {
                // Raw data been written to the file
                /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,encoded()=%d - CALLED!', $groupId, $hash, strlen($encoded)));
                $rawData = sprintf('%s%s%s%s%s',
@@ -649,7 +688,15 @@ abstract class BaseFileStack extends BaseStacker {
                $gapPosition = $this->getIteratorInstance()->searchNextGap(strlen($rawData));
 
                // Gap position cannot be smaller than header length + 1
-               assert($gapPosition > $this->getIteratorInstance()->getHeaderSize());
+               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: gapPosition=%d', $gapPosition));
+               if ($gapPosition <= $this->getIteratorInstance()->getHeaderSize()) {
+                       // Improper gap position
+                       throw new UnexpectedValueException(sprintf('gapPosition[%s]=%d is not larger than headerSize=%d',
+                               gettype($gapPosition),
+                               $gapPosition,
+                               $this->getIteratorInstance()->getHeaderSize()
+                       ));
+               }
 
                // Then write the data at that gap
                /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,gapPosition=%s', $groupId, $hash, $gapPosition));
@@ -658,9 +705,9 @@ abstract class BaseFileStack extends BaseStacker {
                // Return gap position, hash and length of raw data
                /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,rawData()=%d - EXIT!', $groupId, $hash, strlen($rawData)));
                return [
-                       self::ARRAY_INDEX_GAP_POSITION => $gapPosition,
-                       self::ARRAY_INDEX_HASH         => $hash,
-                       self::ARRAY_INDEX_DATA_LENGTH  => strlen($rawData),
+                       self::ARRAY_NAME_GAP_POSITION => $gapPosition,
+                       self::ARRAY_NAME_HASH         => $hash,
+                       self::ARRAY_NAME_DATA_LENGTH  => strlen($rawData),
                ];
        }