08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
SPL: The Missing Link in Development
1. SPL: The Missing Link in Development
Jake Smith
Dallas PHP - 7/13/2010
2. What is SPL?
• A
library
of
standard
interfaces,
classes,
and
functions
designed
to
solve
common
programming
problems
and
allow
engine
overloading.
Definition Source: http://elizabethmariesmith.com/
3. SPL Background
• Provides Interfaces, Classes and Functions
• As of PHP 5.3 you can not turn off SPL
• Poor documentation root of poor
adoption.
10. iterator_to_array
• Takes an iterator object, an object that
implements Traversable
• All iterators implement Traversable
11. spl_object_hash
• MD5 hash of internal pointer
• When objects are destroyed their object
hash is released
• Object Hash ID can/will be reused after
destruction.
13. ArrayObject
• Allows objects to act like arrays
• Does not allow usage of array functions on
object
• Built in methods: ksort, usort, asort,
getArrayCopy
14. SplFileInfo
• Object that returns information on Files/
Folders
• isDir, isFile, isReadable, isWritable, getPerms
(returns int), etc.
Example Source: http://us3.php.net/manual/en/class.splfileinfo.php
17. SplSubject
<?php
class ExceptionHandler implements SplSubject
{
private $_observers = array();
public function attach(SplObserver $observer)
{
$id = spl_object_hash($observer);
$this->_observers[$id] = $observer;
}
public function detach(SplObserver $observer)
{
$id = spl_object_hash($observer);
unset($this->_observers[$id]);
}
public function notify()
{
foreach($this->_observers as $obs) {
$obs->update($this);
}
}
public function handle(Exception $e)
{
$this->exception = $e;
$this->notify();
}
}
Example Source: http://devzone.zend.com/article/12229
18. SplObserver
Class Mailer implements SplObserver {
public function update(SplSubject $subject)
{
// Do something with subject object
}
}
// Create the ExceptionHandler
$handler = new ExceptionHandler();
// Attach an Exception Logger and Mailer
$handler->attach(new Mailer());
// Set ExceptionHandler::handle() as the default
set_exception_handler(array($handler, 'handle'));
Example Source: http://devzone.zend.com/article/12229
19. ArrayAccess
• OffsetExists - Values exists for key, returns
boolean
• OffsetSet - Set value for key
• OffsetGet - Return value for key
• OffsetUnset - Remove value from array
• Note that if the array is numerically indexed, a call to array_values() will be required to re-index
the array if that is the behaviour required.
Example Source: http://www.phpro.org/tutorials/Introduction-to-SPL-ArrayAccess.html
20. ArrayAccess Example
<?php
class book implements ArrayAccess
{
public $title;
public $author;
public $isbn;
public function offsetExists( $offset )
{
return isset( $this->$offset );
}
public function offsetSet( $offset, $value)
{
$this->$offset = $value;
}
public function offsetGet( $offset )
{
return $this->$offset;
}
public function offsetUnset( $offset )
{
unset( $this->$offset );
}
}
Example Source: http://www.phpro.org/tutorials/Introduction-to-SPL-ArrayAccess.html
21. Iterator
• Provides basic iterator functionality
(foreach)
• Interface requires the following methods
• current(), key(), next(), rewind(), valid()
22. Recursive Iterator
• A foreach only goes top level, but many
times you need to dig deeper
• Recursive Iterator extends Iterator and
requires hasChildren() and getChildren()
23. Countable
• Internal Counter
<?php
class loopy
{
public function count()
{
static $count = 0;
return $count++;
}
public function access()
{
$this->count();
// Method logic
}
}
24. SeekableIterator
• Other iterators must start at beginning of
an array, but seekable allows you to change
iteration start point.
<?php
class PartyMemberIterator implements SeekableIterator
{
public function seek($index)
{
$this->rewind();
$position = 0;
while ($position < $index && $this->valid()) {
$this->next();
$position++;
}
if (!$this->valid()) {
throw new OutOfBoundsException('Invalid position');
}
}
Example Source: http://devzone.zend.com/article/2565
27. ArrayIterator
<?php
// Using While
/*** create a new object ***/
$object = new ArrayIterator($array);
/*** rewind to the beginning of the array ***/
$object->rewind();
/*** check for valid member ***/
while($object->valid())
{
/*** echo the key and current value ***/
echo $object->key().' -> '.$object->current().'<br />';
/*** hop to the next array member ***/
$object->next();
}
// Using Foreach
$object = new ArrayIterator($array);
foreach($object as $key=>$value)
{
echo $key.' => '.$value.'<br />';
}
Example Source: http://www.phpro.org/tutorials/Introduction-to-SPL.html#6
28. LimitIterator
• Used similar to Limit in SQL
<?php
// Show 10 files/folders starting from the 3rd.
$offset = 3;
$limit = 10;
$filepath = '/var/www/vhosts/mysite/images'
$it = new LimitIterator(new DirectoryIterator($filepath), $offset, $limit);
foreach($it as $r)
{
// output the key and current array value
echo $it->key().' -- '.$it->current().'<br />';
}
30. DirectoryIterator
<?php <?php
$hdl = opendir('./'); try
while ($dirEntry = readdir($hdl)) {
{ /*** class create new DirectoryIterator Object ***/
if (substr($dirEntry, 0, 1) != '.') foreach ( new DirectoryIterator('./') as $Item )
{ {
if(!is_file($dirEntry)) echo $Item.'<br />';
{ }
continue; }
} /*** if an exception is thrown, catch it here ***/
$listing[] = $dirEntry; catch(Exception $e)
} {
} echo 'No files Found!<br />';
closedir($hdl); }
foreach($listing as $my_file)
{
echo $my_file.'<br />';
}
31. RecursiveDirectory
Iterator
• Move out of the top level and get all
children files/folders
<?php
$dir = '/Users/jsmith/Sites/vhosts/test.local/wwwroot';
$iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($dir));
// could use CHILD_FIRST if you so wish
foreach ($iterator as $file) {
echo $file . "<br />";
}
32. GlobIterator (5.3)
• Very Similar to DirectoryIterator
• Only use if you want to convert old glob
code into an iterator object
• returns SplFileInfo Objects
35. SplFixedArray
• Array with pre-defined dimensions
• Shows great speed for setting and
retrieving
• If you change Array dimensions, it will
crawl.
36. SplHeap
• Automatically reorder after insert, based
off of compare() method
• Extract is similar to array_shift()
• Great memory usage!
Example Source: http://www.slideshare.net/tobias382/new-spl-features-in-php-53
37. SplMaxHeap
• Subclass of SplHeap
• When you extract() a value it will return in
order from greatest to least
<?php
$heap = new SplMaxHeap();
$heap->insert('b');
$heap->insert('a');
$heap->insert('c');
echo $heap->extract()."n";
echo $heap->extract()."n";
echo $heap->extract()."n";
// OUTPUT:
// c
// b
// a
Example Source: http://www.alberton.info/php_5.3_spl_data_structures.html
38. SplMinHeap
• Subclass of SplHeap
• When you extract() a value it will return in
order from least to greatest
<?php
$heap = new SplMinHeap();
$heap->insert('b');
$heap->insert('a');
$heap->insert('c');
echo $heap->extract()."n";
echo $heap->extract()."n";
echo $heap->extract()."n";
// OUTPUT:
// a
// b
// c
Example Source: http://www.alberton.info/php_5.3_spl_data_structures.html
39. SplDoublyLinkedList
• Do not know size of list/array
• Can only be read sequentially
• Less processing power required, on large
data sets provides better memory usage
