3 * A database result class
5 * @author Roland Haeder <webmaster@shipsimu.org>
7 * @copyright Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2014 Core Developer Team
8 * @license GNU GPL 3.0 or any newer version
9 * @link http://www.shipsimu.org
11 * This program is free software: you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation, either version 3 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 class CachedDatabaseResult extends BaseFrameworkSystem implements SearchableResult, UpdateableResult, SeekableIterator {
25 // Exception constants
26 const EXCEPTION_INVALID_DATABASE_RESULT = 0x1c0;
27 const EXCEPTION_RESULT_UPDATE_FAILED = 0x1c1;
30 * Current position in array
32 private $currentPos = -1;
37 private $currentRow = NULL;
42 private $resultArray = array();
45 * Array of out-dated entries
47 private $outDated = array();
52 private $affectedRows = 0;
57 private $foundValue = '';
60 * Protected constructor
64 protected function __construct () {
65 // Call parent constructor
66 parent::__construct(__CLASS__);
70 * Creates an instance of this result by a provided result array
72 * @param $resultArray The array holding the result from query
73 * @return $resultInstance An instance of this class
75 public static final function createCachedDatabaseResult (array $resultArray) {
77 $resultInstance = new CachedDatabaseResult();
79 // Set the result array
80 $resultInstance->setResultArray($resultArray);
83 $resultInstance->setAffectedRows(count($resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS]));
85 // Return the instance
86 return $resultInstance;
90 * Setter for result array
92 * @param $resultArray The array holding the result from query
95 protected final function setResultArray (array $resultArray) {
96 $this->resultArray = $resultArray;
100 * Updates the current entry by given update criteria
102 * @param $updateInstance An instance of an Updateable criteria
105 private function updateCurrentEntryByCriteria (LocalUpdateCriteria $updateInstance) {
106 // Get the current entry key
107 $entryKey = $this->key();
109 // Now get the update criteria array and update all entries
110 foreach ($updateInstance->getUpdateCriteria() as $criteriaKey => $criteriaValue) {
112 $this->resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS][$entryKey][$criteriaKey] = $criteriaValue;
114 // Mark it as out-dated
115 $this->outDated[$criteriaKey] = 1;
120 * "Iterator" method next() to advance to the next valid entry. This method
121 * does also check if result is invalid
123 * @return $nextValid Whether the next entry is valid
125 public function next () {
126 // Default is not valid
129 // Is the result valid?
130 if ($this->valid()) {
131 // Next entry found, so count one up and cache it
133 $this->currentRow = $this->resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS][$this->currentPos];
142 * Seeks for to a specified position
144 * @param $index Index to seek for
147 public function seek ($index) {
148 // Rewind to beginning
151 // Search for the entry
152 while (($this->currentPos < $index) && ($this->valid())) {
159 * Gives back the current position or null if not found
161 * @return $current Current element to give back
163 public function current () {
164 // Default is not found
167 // Does the current enty exist?
168 if (isset($this->resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS][$this->currentPos])) {
170 $current = $this->resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS][$this->currentPos];
178 * Checks if next() and rewind will give a valid result
180 * @return $isValid Whether the next/rewind entry is valid
182 public function valid () {
183 // By default nothing is valid
187 //*NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] this->currentPos=' . $this->currentPos);
189 // Check if all is fine ...
190 if (($this->ifStatusIsOkay()) && (isset($this->resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS][($this->currentPos + 1)])) && (isset($this->resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS][0]))) {
200 * Returns count of entries
202 * @return $isValid Whether the next/rewind entry is valid
204 public function count () {
206 return count($this->resultArray[BaseDatabaseBackend::RESULT_INDEX_ROWS]);
210 * Determines whether the status of the query was fine (BaseDatabaseBackend::RESULT_OKAY)
212 * @return $ifStatusOkay Whether the status of the query was okay
214 public function ifStatusIsOkay () {
215 $ifStatusOkay = ((isset($this->resultArray[BaseDatabaseBackend::RESULT_INDEX_STATUS])) && ($this->resultArray[BaseDatabaseBackend::RESULT_INDEX_STATUS] === BaseDatabaseBackend::RESULT_OKAY));
216 //*NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('[' . __METHOD__ . ':' . __LINE__ . '] ifStatusOkay=' . intval($ifStatusOkay));
217 return $ifStatusOkay;
221 * Gets the current key of iteration
223 * @return $currentPos Key from iterator
225 public function key () {
226 return $this->currentPos;
230 * Rewind to the beginning and clear array $currentRow
234 public function rewind () {
235 $this->currentPos = -1;
236 $this->currentRow = array();
240 * Searches for an entry in data result and returns it
242 * @param $criteriaInstance The criteria to look inside the data set
243 * @return $result Found result entry
246 public function searchEntry (LocalSearchCriteria $criteriaInstance) {
247 $this->debugBackTrace('[' . '[' . __METHOD__ . ':' . __LINE__ . ']: Unfinished!');
251 * Adds an update request to the database result for writing it to the
254 * @param $criteriaInstance An instance of a updateable criteria
256 * @throws ResultUpdateException If no result was updated
258 public function add2UpdateQueue (LocalUpdateCriteria $criteriaInstance) {
259 // Rewind the pointer
262 // Get search criteria
263 $searchInstance = $criteriaInstance->getSearchInstance();
265 // And start looking for the result
267 while (($this->valid()) && ($foundEntries < $searchInstance->getLimit())) {
270 $currentEntry = $this->current();
272 // Is this entry found?
273 if ($searchInstance->ifEntryMatches($currentEntry)) {
275 $this->updateCurrentEntryByCriteria($criteriaInstance);
282 // If no entry is found/updated throw an exception
283 if ($foundEntries == 0) {
284 // Throw an exception here
285 throw new ResultUpdateException($this, self::EXCEPTION_RESULT_UPDATE_FAILED);
289 $this->setAffectedRows($foundEntries);
291 // Set update instance
292 $this->setUpdateInstance($criteriaInstance);
296 * Setter for affected rows
298 * @param $rows Number of affected rows
301 public final function setAffectedRows ($rows) {
302 $this->affectedRows = $rows;
306 * Getter for affected rows
308 * @return $rows Number of affected rows
310 public final function getAffectedRows () {
311 return $this->affectedRows;
315 * Getter for found value of previous found() call
317 * @return $foundValue Found value of previous found() call
319 public final function getFoundValue () {
320 return $this->foundValue;
324 * Checks whether we have out-dated entries or not
326 * @return $needsUpdate Whether we have out-dated entries
328 public function ifDataNeedsFlush () {
329 $needsUpdate = (count($this->outDated) > 0);
334 * Adds registration elements to a given dataset instance
336 * @param $criteriaInstance An instance of a StoreableCriteria class
337 * @param $requestInstance An instance of a Requestable class
340 public function addElementsToDataSet (StoreableCriteria $criteriaInstance, Requestable $requestInstance = NULL) {
341 // Walk only through out-dated columns
342 foreach ($this->outDated as $key => $dummy) {
343 // Does this key exist?
344 //* DEBUG: */ echo "outDated: {$key}<br />\n";
345 if ($this->find($key)) {
347 $criteriaInstance->addCriteria($key, $this->getFoundValue());
353 * Find a key inside the result array
355 * @param $key The key we shall find
356 * @return $found Whether the key was found or not
358 public function find ($key) {
359 // By default nothing is found
362 // Rewind the pointer
365 // Walk through all entries
366 while ($this->valid()) {
367 // Advance to next entry
370 // Get the whole array
371 $currentEntry = $this->current();
373 // Is the element there?
374 if (isset($currentEntry[$key])) {
379 $this->foundValue = $currentEntry[$key];
381 // And stop searching
391 * Solver for result index value with call-back method
393 * @param $databaseColumn Database column where the index might be found
394 * @param $wrapperInstance The wrapper instance to ask for array element
395 * @para $callBack Call-back object for setting the index;
396 * 0=object instance,1=method name
398 * @todo Find a caching way without modifying the result array
400 public function solveResultIndex ($databaseColumn, DatabaseWrapper $wrapperInstance, array $callBack) {
401 // By default nothing is found
404 // Is the element in result itself found?
405 if ($this->find($databaseColumn)) {
407 $indexValue = $this->getFoundValue();
408 } elseif ($this->find($wrapperInstance->getIndexKey())) {
410 $indexValue = $this->getFoundValue();
414 call_user_func_array($callBack, array($indexValue));