Added missing setter.
[core.git] / inc / classes / main / stacker / file / class_BaseFileStack.php
index 47b7b5ce6b431c0a8edbd0a19b039d4e959c9a2c..e3aeb4701fb9c3f192b7fa9cec788448e13cfb61 100644 (file)
@@ -77,6 +77,16 @@ class BaseFileStack extends BaseStacker {
         */
        private $header = array();
 
+       /**
+        * Seek positions for gaps ("fragmentation")
+        */
+       private $gaps = array();
+
+       /**
+        * Seek positions for damaged entries (e.g. mismatching hash sum, ...)
+        */
+       private $damagedEntries = array();
+
        /**
         * Protected constructor
         *
@@ -89,13 +99,34 @@ class BaseFileStack extends BaseStacker {
 
                // Calculate header size
                $this->headerSize = (
-                       strlen(self::MAGIC) +
+                       strlen(self::STACK_MAGIC) +
                        strlen(self::SEPARATOR_HEADER_DATA) +
                        self::LENGTH_COUNT +
                        strlen(self::SEPARATOR_HEADER_DATA) +
                        self::LENGTH_POSITION +
                        strlen(self::SEPARATOR_HEADER_ENTRIES)
                );
+
+               // Init counters and gaps array
+               $this->initCountersGapsArray();
+       }
+
+       /**
+        * Initializes counter for valid entries, arrays for damaged entries and
+        * an array for gap seek positions. If you call this method on your own,
+        * please re-analyze the file structure. So you are better to call
+        * analyzeStackFile() instead of this method.
+        *
+        * @return      void
+        */
+       private function initCountersGapsArray () {
+               // Init counter and seek position
+               $this->setCounter(0);
+               $this->setSeekPosition(0);
+
+               // Init arrays
+               $this->gaps = array();
+               $this->damagedEntries = array();
        }
 
        /**
@@ -103,17 +134,28 @@ class BaseFileStack extends BaseStacker {
         *
         * @return      $totalEntries   Total entries in this stack
         */
-       private function getCounter () {
+       private final function getCounter () {
                // Get it
                return $this->totalEntries;
        }
 
+       /**
+        * Setter for total entries
+        *
+        * @param       $totalEntries   Total entries in this stack
+        * @return      void
+        */
+       private final function setCounter ($counter) {
+               // Set it
+               $this->totalEntries = $counter;
+       }
+
        /**
         * Increment counter
         *
         * @return      void
         */
-       private function incrementCounter () {
+       private final function incrementCounter () {
                // Get it
                $this->totalEntries++;
        }
@@ -123,7 +165,7 @@ class BaseFileStack extends BaseStacker {
         *
         * @return      $seekPosition   Current seek position (stored here in object)
         */
-       private function getSeekPosition () {
+       private final function getSeekPosition () {
                // Get it
                return $this->seekPosition;
        }
@@ -134,7 +176,7 @@ class BaseFileStack extends BaseStacker {
         * @param       $seekPosition   Current seek position (stored here in object)
         * @return      void
         */
-       private function setSeekPosition ($seekPosition) {
+       private final function setSeekPosition ($seekPosition) {
                // And set it
                $this->seekPosition = $seekPosition;
        }
@@ -145,16 +187,16 @@ class BaseFileStack extends BaseStacker {
         * @return      void
         */
        private function updateSeekPosition () {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 
                // Get key (= seek position)
                $seekPosition = $this->getIteratorInstance()->key();
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Setting seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Setting seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
 
                // And set it here
                $this->setSeekPosition($seekPosition);
 
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
        }
 
        /**
@@ -163,16 +205,23 @@ class BaseFileStack extends BaseStacker {
         * @return      void
         */
        private function readFileHeader () {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 
                // First rewind to beginning as the header sits at the beginning ...
                $this->getIteratorInstance()->rewind();
 
                // Then read it (see constructor for calculation)
-               $data = $this->getIteratorInstance()->read($this->headerLength);
+               $data = $this->getIteratorInstance()->read($this->headerSize);
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Read %d bytes (%d wanted).', __METHOD__, __LINE__, strlen($data), $this->headerSize));
+
+               // Have all requested bytes been read?
+               assert(strlen($data) == $this->headerSize);
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 
                // Last character must be the separator
-               assert(substr($data, -1, 1) == self::SEPARATOR_HEADER_ENTRIES);
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] data(-1)=%s', __METHOD__, __LINE__, dechex(ord(substr($data, -1, 1)))));
+               assert(substr($data, -1, 1) == chr(self::SEPARATOR_HEADER_ENTRIES));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 
                // Okay, then remove it
                $data = substr($data, 0, -1);
@@ -187,23 +236,28 @@ class BaseFileStack extends BaseStacker {
                 * 1 => Total entries
                 * 2 => Current seek position
                 */
-               $this->header = explode(self::SEPARATOR_HEADER_DATA, $data);
+               $this->header = explode(chr(self::SEPARATOR_HEADER_DATA), $data);
 
                // Check if the array has only 3 elements
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] header(%d)=%s', __METHOD__, __LINE__, count($this->header), print_r($this->header, TRUE)));
                assert(count($this->header) == 3);
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 
                // Check magic
-               assert($this->header[0] == self::MAGIC);
+               assert($this->header[0] == self::STACK_MAGIC);
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 
                // Check length of count and seek position
                assert(strlen($this->header[1]) == self::LENGTH_COUNT);
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
                assert(strlen($this->header[2]) == self::LENGTH_POSITION);
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Passed assert().', __METHOD__, __LINE__));
 
                // Decode count and seek position
                $this->header[1] = hex2bin($this->header[1]);
                $this->header[2] = hex2bin($this->header[2]);
 
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
        }
 
        /**
@@ -212,7 +266,7 @@ class BaseFileStack extends BaseStacker {
         * @return      $isInitialized  Whether the file header is initialized
         */
        private function isFileHeaderInitialized () {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
                // Default is not initialized
                $isInitialized = FALSE;
 
@@ -220,7 +274,7 @@ class BaseFileStack extends BaseStacker {
                if ($this->isFileInitialized()) {
                        // Some bytes has been written, so rewind to start of it.
                        $rewindStatus = $this->getIteratorInstance()->rewind();
-                       /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] rewindStatus=%s', __METHOD__, __LINE__, $rewindStatus));
+                       //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] rewindStatus=%s', __METHOD__, __LINE__, $rewindStatus));
 
                        // Is the rewind() call successfull?
                        if ($rewindStatus != 1) {
@@ -231,11 +285,12 @@ class BaseFileStack extends BaseStacker {
                        // Read file header
                        $this->readFileHeader();
 
-                       // Check if its format is valid.
+                       // The above method does already check the header
+                       $isInitialized = TRUE;
                } // END - if
 
                // Return result
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
                return $isInitialized;
        }
 
@@ -245,11 +300,11 @@ class BaseFileStack extends BaseStacker {
         * @return      $isInitialized          Whether the file's size is zero
         */
        private function isFileInitialized () {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 
                // Get it from iterator which holds the pointer instance. If FALSE is returned
                $fileSize = $this->getIteratorInstance()->size();
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] fileSize=%s', __METHOD__, __LINE__, $fileSize));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] fileSize=%s', __METHOD__, __LINE__, $fileSize));
 
                /*
                 * The returned file size should not be FALSE or NULL as this means
@@ -261,7 +316,7 @@ class BaseFileStack extends BaseStacker {
                $isInitialized = ($fileSize > 0);
 
                // Return result
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] isInitialized=%d - EXIT!', __METHOD__, __LINE__, intval($isInitialized)));
                return $isInitialized;
        }
 
@@ -271,14 +326,14 @@ class BaseFileStack extends BaseStacker {
         * @return      void
         */
        private function createFileHeader () {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
                // The file's header should not be initialized here
                assert(!$this->isFileHeaderInitialized());
 
                // Simple flush file header which will create it.
                $this->flushFileHeader();
 
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!!', __METHOD__, __LINE__));
        }
 
        /**
@@ -287,7 +342,7 @@ class BaseFileStack extends BaseStacker {
         * @return      void
         */
        private function flushFileHeader () {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 
                // Put all informations together
                $header = sprintf('%s%s%s%s%s%s',
@@ -313,7 +368,7 @@ class BaseFileStack extends BaseStacker {
                // Write it to disk (header is always at seek position 0)
                $this->writeData(0, $header);
 
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
        }
 
        /**
@@ -324,7 +379,7 @@ class BaseFileStack extends BaseStacker {
         * @return      void
         */
        private function writeData ($seekPosition, $data) {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data()=%s - CALLED!', __METHOD__, __LINE__, $seekPosition, strlen($data)));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s,data()=%s - CALLED!', __METHOD__, __LINE__, $seekPosition, strlen($data)));
 
                // Write data at given position
                $this->getIteratorInstance()->writeAtPosition($seekPosition, $data);
@@ -332,7 +387,7 @@ class BaseFileStack extends BaseStacker {
                // Update seek position
                $this->updateSeekPosition();
 
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
        }
 
        /**
@@ -341,7 +396,7 @@ class BaseFileStack extends BaseStacker {
         * @return      void
         */
        private function preAllocateFile () {
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
 
                // Is it enabled?
                if ($this->getConfigInstance()->getConfigEntry('file_stack_pre_allocate_enabled') != 'Y') {
@@ -360,26 +415,49 @@ class BaseFileStack extends BaseStacker {
                 * minimum length = hash length + separator + name + minimum entry size = ?? + 1 + 10 + 1 = ??
                 */
                $minLengthEntry = self::getHashLength() + strlen(self::SEPARATOR_HASH_NAME) + self::LENGTH_NAME + 1;
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] minLengthEntry=%s', __METHOD__, __LINE__, $minLengthEntry));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] minLengthEntry=%s', __METHOD__, __LINE__, $minLengthEntry));
 
                // Calulcate seek position
                $seekPosition = $minLengthEntry * $this->getConfigInstance()->getConfigEntry('file_stack_pre_allocate_count');
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekPosition=%s', __METHOD__, __LINE__, $seekPosition));
 
                // Now simply write a NUL there. This will pre-allocate the file.
                $this->writeData($seekPosition, chr(0));
 
-               /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
+       }
+
+       /**
+        * Analyzes entries in stack file. This will count all found (and valid)
+        * entries, mark invalid as damaged and count gaps ("fragmentation"). If
+        * only gaps are found, the file is considered as "virgin" (no entries).
+        *
+        * @return      void
+        */
+       private function analyzeStackFile () {
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));
+
+               // Make sure the file is initialized
+               assert($this->isFileInitialized());
+
+               // Init counters and gaps array
+               $this->initCountersGapsArray();
+
+               // Output message (as this may take some time)
+               self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] Analyzing file structure ... (this may take some time)', __METHOD__, __LINE__));
+
+               //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] EXIT!', __METHOD__, __LINE__));
        }
 
        /**
         * Initializes this file-based stack.
         *
         * @param       $fileName       File name of this stack
+        * @param       $type           Type of this stack (e.g. url_source for URL sources)
         * @return      void
         */
-       protected function initFileStack ($fileName) {
-               // Get a file i/o pointer instance
+       protected function initFileStack ($fileName, $type) {
+               // Get a file i/o pointer instance for stack file
                $pointerInstance = ObjectFactory::createObjectByConfiguredName('file_raw_input_output_class', array($fileName));
 
                // Get iterator instance
@@ -392,72 +470,28 @@ class BaseFileStack extends BaseStacker {
                $this->setIteratorInstance($iteratorInstance);
 
                // Is the file's header initialized?
-               if ($this->isFileHeaderInitialized()) {
-                       // Then load it
-                       $this->loadFileHeader();
-               } else {
+               if (!$this->isFileHeaderInitialized()) {
                        // No, then create it (which may pre-allocate the stack)
                        $this->createFileHeader();
 
                        // And pre-allocate a bit
                        $this->preAllocateFile();
-               }
-       }
-
-       /**
-        * Initializes given stacker
-        *
-        * @param       $stackerName    Name of the stack
-        * @param       $forceReInit    Force re-initialization
-        * @return      void
-        * @throws      AlreadyInitializedStackerException      If the stack is already initialized
-        */
-       public function initStack ($stackerName, $forceReInit = FALSE) {
-               // Is the stack already initialized?
-               if (($forceReInit === FALSE) && ($this->isStackInitialized($stackerName))) {
-                       // Then throw the exception
-                       throw new AlreadyInitializedStackerException(array($this, $stackerName, $forceReInit), self::EXCEPTION_STACKER_ALREADY_INITIALIZED);
                } // END - if
 
-               // Initialize the given stack
-               $this->partialStub('stackerName=' . $stackerName . ',forceReInit=' . intval($forceReInit));
-       }
+               // Load the file header
+               $this->readFileHeader();
 
-       /**
-        * Checks whether the given stack is initialized (set in array $stackers)
-        *
-        * @param       $stackerName    Name of the stack
-        * @return      $isInitialized  Whether the stack is initialized
-        */
-       public function isStackInitialized ($stackerName) {
-               // Is is there?
-               $this->partialStub('stackerName=' . $stackerName);
-               $isInitialized = TRUE;
+               // Count all entries in file
+               $this->analyzeStackFile();
 
-               // Return result
-               return $isInitialized;
-       }
-
-       /**
-        * Getter for size of given stack (array count)
-        *
-        * @param       $stackerName    Name of the stack
-        * @return      $count                  Size of stack (array count)
-        * @throws      NoStackerException      If given stack is missing
-        */
-       public function getStackCount ($stackerName) {
-               // Is the stack not yet initialized?
-               if (!$this->isStackInitialized($stackerName)) {
-                       // Throw an exception
-                       throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
-               } // END - if
-
-               // Now, count the array of entries
-               $this->partialStub('stackerName=' . $stackerName);
-               $count = 0;
+               /*
+                * Get stack index instance. This can be used for faster
+                * "defragmentation" and startup.
+                */
+               $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileName, $type);
 
-               // Return result
-               return $count;
+               // And set it here
+               $this->setIndexInstance($indexInstance);
        }
 
        /**
@@ -466,17 +500,14 @@ class BaseFileStack extends BaseStacker {
         * @param       $stackerName    Name of the stack
         * @param       $value                  Value to add to this stacker
         * @return      void
-        * @throws      FullStackerException    Thrown if the stack is full
+        * @throws      FullStackerException    If the stack is full
         */
        protected function addValue ($stackerName, $value) {
-               // Is the stack not yet initialized or full?
-               if (!$this->isStackInitialized($stackerName)) {
-                       // Then do it here
-                       $this->initStack($stackerName);
-               } elseif ($this->isStackFull($stackerName)) {
+               // Do some tests
+               if ($this->isStackFull($stackerName)) {
                        // Stacker is full
                        throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
-               }
+               } // END - if
 
                // Now add the value to the stack
                $this->partialStub('stackerName=' . $stackerName . ',value[]=' . gettype($value));
@@ -487,18 +518,14 @@ class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value of last added value
-        * @throws      NoStackerException      If the named stacker was not found
-        * @throws      EmptyStackerException   If the named stacker is empty
+        * @throws      EmptyStackerException   If the stack is empty
         */
        protected function getLastValue ($stackerName) {
                // Is the stack not yet initialized or full?
-               if (!$this->isStackInitialized($stackerName)) {
-                       // Throw an exception
-                       throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
-               } elseif ($this->isStackEmpty($stackerName)) {
+               if ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
                        throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               }
+               } // END - if
 
                // Now get the last value
                $this->partialStub('stackerName=' . $stackerName);
@@ -513,18 +540,14 @@ class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value of last added value
-        * @throws      NoStackerException      If the named stacker was not found
-        * @throws      EmptyStackerException   If the named stacker is empty
+        * @throws      EmptyStackerException   If the stack is empty
         */
        protected function getFirstValue ($stackerName) {
                // Is the stack not yet initialized or full?
-               if (!$this->isStackInitialized($stackerName)) {
-                       // Throw an exception
-                       throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
-               } elseif ($this->isStackEmpty($stackerName)) {
+               if ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
                        throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               }
+               } // END - if
 
                // Now get the first value
                $this->partialStub('stackerName=' . $stackerName);
@@ -539,18 +562,14 @@ class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value "poped" from array
-        * @throws      NoStackerException      If the named stacker was not found
-        * @throws      EmptyStackerException   If the named stacker is empty
+        * @throws      EmptyStackerException   If the stack is empty
         */
        protected function popLast ($stackerName) {
                // Is the stack not yet initialized or full?
-               if (!$this->isStackInitialized($stackerName)) {
-                       // Throw an exception
-                       throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
-               } elseif ($this->isStackEmpty($stackerName)) {
+               if ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
                        throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               }
+               } // END - if
 
                // Now, remove the last entry, we don't care about the return value here, see elseif() block above
                $this->partialStub('stackerName=' . $stackerName);
@@ -562,23 +581,93 @@ class BaseFileStack extends BaseStacker {
         *
         * @param       $stackerName    Name of the stack
         * @return      $value                  Value "shifted" from array
-        * @throws      NoStackerException      If the named stacker was not found
         * @throws      EmptyStackerException   If the named stacker is empty
         */
        protected function popFirst ($stackerName) {
                // Is the stack not yet initialized or full?
-               if (!$this->isStackInitialized($stackerName)) {
-                       // Throw an exception
-                       throw new NoStackerException(array($this, $stackerName), self::EXCEPTION_NO_STACKER_FOUND);
-               } elseif ($this->isStackEmpty($stackerName)) {
+               if ($this->isStackEmpty($stackerName)) {
                        // Throw an exception
                        throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
-               }
+               } // END - if
 
                // Now, remove the last entry, we don't care about the return value here, see elseif() block above
                $this->partialStub('stackerName=' . $stackerName);
                return NULL;
        }
+
+       /**
+        * Checks whether the given stack is full
+        *
+        * @param       $stackerName    Name of the stack
+        * @return      $isFull                 Whether the stack is full
+        */
+       protected function isStackFull ($stackerName) {
+               // File-based stacks will only run full if the disk space is low.
+               // @TODO Please implement this, returning FALSE
+               $isFull = FALSE;
+
+               // Return result
+               return $isFull;
+       }
+
+       /**
+        * Checks whether the given stack is empty
+        *
+        * @param       $stackerName            Name of the stack
+        * @return      $isEmpty                        Whether the stack is empty
+        * @throws      NoStackerException      If given stack is missing
+        */
+       public function isStackEmpty ($stackerName) {
+               // So, is the stack empty?
+               $isEmpty = (($this->getStackCount($stackerName)) == 0);
+
+               // Return result
+               return $isEmpty;
+       }
+
+       /**
+        * Initializes given stacker
+        *
+        * @param       $stackerName    Name of the stack
+        * @param       $forceReInit    Force re-initialization
+        * @return      void
+        * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
+        */
+       public function initStack ($stackerName, $forceReInit = FALSE) {
+               throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
+       }
+
+       /**
+        * Initializes all stacks
+        *
+        * @return      void
+        * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
+        */
+       public function initStacks (array $stacks, $forceReInit = FALSE) {
+               throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
+       }
+
+       /**
+        * Checks whether the given stack is initialized (set in array $stackers)
+        *
+        * @param       $stackerName    Name of the stack
+        * @return      $isInitialized  Whether the stack is initialized
+        * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
+        */
+       public function isStackInitialized ($stackerName) {
+               throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
+       }
+
+       /**
+        * Getter for size of given stack (array count)
+        *
+        * @param       $stackerName    Name of the stack
+        * @return      $count                  Size of stack (array count)
+        */
+       public function getStackCount ($stackerName) {
+               // Now, simply return the found count value, this must be up-to-date then!
+               return $this->getCounter();
+       }
 }
 
 // [EOF]