/**
* (PHP 5 >= 5.0.0)<br/>
* Move forward to next element
* @link http://php.net/manual/en/iterator.next.php
* @return void Any returned value is ignored.
*/
public function next()
{
do {
$this->line = $this->serializer->fgets($this->resource);
} while ($this->line == "\n");
if ($this->line !== FALSE) {
$this->key++;
}
}
/**
* Scan TSV file and return the keys, offsets and lengths of each line
*
* @param string $tsv
* @param int[] $sortPositions
* @param TsvSerializerInterface $serializer
* @return array
*/
private function index($tsv, $sortPositions, $serializer)
{
$keys = array();
$offsets = array();
$lengths = array();
$resource = $this->fopen($tsv, "r");
$offset = $this->ftell($resource);
while (($line = $serializer->fgets($resource)) !== FALSE) {
if ($line == "\n") {
continue;
}
$values = $serializer->unserialize($line);
$keys[] = $this->constructKey($values, $sortPositions);
$offsets[] = $offset;
$lengths[] = ($newOffset = $this->ftell($resource)) - $offset;
$offset = $newOffset;
}
$this->close($resource);
return array($keys, $offsets, $lengths);
}
