109 lines
2.7 KiB
PHP
109 lines
2.7 KiB
PHP
<?php
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/**
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* @package default
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* @copyright Copyright (c) 2010, The volkszaehler.org project
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* @license http://www.gnu.org/licenses/gpl.txt GNU Public License
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*/
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/*
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* This file is part of volkzaehler.org
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*
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* volkzaehler.org is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* any later version.
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*
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* volkzaehler.org is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with volkszaehler.org. If not, see <http://www.gnu.org/licenses/>.
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*/
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namespace Volkszaehler\Interpreter;
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use Volkszaehler\Util;
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use Doctrine\DBAL;
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/**
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* @author Steffen Vogel <info@steffenvogel.de>
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* @package default
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*/
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class DataIterator implements \Iterator, \Countable {
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protected $stmt; // PDO statement
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protected $current; // the current data
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protected $key; // key
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private $rowKey; // internal key for PDO statement
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protected $rowCount; // num of readings in PDOStatement
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protected $tupleCount; // num of requested tuples
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protected $packageSize; // num of rows we aggregate in each tuple
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/**
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* Constructor
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*
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* @param \PDOStatement $stmt
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* @param integer $size
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* @param integer $tuples
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*/
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public function __construct(\PDOStatement $stmt, $rowCount, $tupleCount) {
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$this->rowCount = $rowCount;
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$this->tupleCount = $tupleCount;
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$this->stmt = $stmt;
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$this->stmt->setFetchMode(\PDO::FETCH_NUM);
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if ($this->rowCount > $this->tupleCount) {
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$this->packageSize = floor($this->rowCount / $this->tupleCount);
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$this->tupleCount = floor($this->rowCount / $this->packageSize) + 1;
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}
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else {
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$this->packageSize = 1;
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}
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}
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/**
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* Aggregate data
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*/
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public function next() {
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$package = array(0, 0, 0);
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for ($i = 0; $i < $this->packageSize && $this->valid(); $i++) {
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$tuple = $this->stmt->fetch();
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$package[0] = $tuple[0];
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$package[1] += $tuple[1];
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$package[2] += $tuple[2];
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$this->rowKey++;
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}
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$this->key++;
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return $this->current = $package;
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}
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/**
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* Rewind the iterator
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*
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* Should only be called once
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* PDOStatement hasn't a rewind()
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*/
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public function rewind() {
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$this->key = $this->rowKey = 0;
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}
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public function valid() {
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return $this->rowKey < $this->rowCount;
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}
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/**
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* Getter & setter
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*/
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public function getPackageSize() { return $this->packageSize; }
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public function count() { return $this->tupleCount; }
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public function key() { return $this->key; }
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public function current() { return $this->current; }
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}
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?>
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