Introduced CalculatableBlock + basic implementation for valid().

[core.git] / inc / classes / main / iterator / io / class_FileIoIterator.php

diff --git a/inc/classes/main/iterator/io/class_FileIoIterator.php b/inc/classes/main/iterator/io/class_FileIoIterator.php
index 3437d1165902af54a1cc557527ec90cdd924844a..12cf82ea461e8f32fc5e3f32e4b11b6627dbf57a 100644 (file)
--- a/inc/classes/main/iterator/io/class_FileIoIterator.php
+++ b/inc/classes/main/iterator/io/class_FileIoIterator.php
@@ -36,15 +36,19 @@ class FileIoIterator extends BaseIterator implements SeekableWritableFileIterato
         * Creates an instance of this class
         *
         * @param       $pointerInstance        An instance of a InputOutputPointer class
+        * @param       $blockInstance          An instance of a CalculatableBlock class
         * @return      $iteratorInstance       An instance of a Iterator class
         */
-       public final static function createFileIoIterator (InputOutputPointer $pointerInstance) {
+       public final static function createFileIoIterator (InputOutputPointer $pointerInstance, CalculatableBlock $blockInstance) {
                // Get new instance
                $iteratorInstance = new FileIoIterator();
 
                // Set the instance here
                $iteratorInstance->setPointerInstance($pointerInstance);
 
+               // Set the block instance here
+               $iteratorInstance->setBlockInstance($blockInstance);
+
                // Return the prepared instance
                return $iteratorInstance;
        }
@@ -97,10 +101,29 @@ class FileIoIterator extends BaseIterator implements SeekableWritableFileIterato
         * Checks wether the current entry is valid (not at the end of the file).
         * This method will return TRUE if an emptied (nulled) entry has been found.
         *
-        * @return      void
+        * @return      $isValid        Whether the next entry is valid
         */
        public function valid () {
-               $this->partialStub('Please implement this method.');
+               // First calculate minimum block length
+               $length = $this->getBlockInstance()->caluclateMinimumBlockLength();
+
+               // Short be more than zero!
+               assert($length > 0);
+
+               // Get current seek position
+               $seekPosition = $this->key();
+
+               // Then try to read it
+               $data = $this->read($length);
+
+               // If some bytes could be read, all is fine
+               $isValid = ((is_string($data)) && (strlen($data) > 0));
+
+               // Seek back to old position
+               $this->seek($seekPosition);
+
+               // Return result
+               return $isValid;
        }
 
        /**