Working with Directory Iterators and Proxy Classes with PHP 5 - Improving the functionality of the proxy class
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Since the initial functionality provided by the prior "ProxyDirectoryProcessor" class is pretty limited, it would be desirable to add to it some additional methods. These will help with performing some useful tasks, such as retrieving the access timestamps that correspond to the different directory entries, as well as fetching some information concerning the respective index nodes.
Aside from all the operations that I mentioned before, it's necessary to define another specific method. This method will be responsible for creating a directory processor object when this process will be required by the proxy class in question.
Therefore, keeping in mind all the functionality that I want to give to the proxy class, below I listed its improved signature. Have a look at it, please:
// define 'DirectoryProcessor' class
class ProxyDirectoryProcessor{
private $dirPath;
private $dirProcessor=NULL;
public function __construct($dirPath='defaultPath'){
if(!is_dir($dirPath)){
throw new Exception('Invalid input directory');
}
$this->dirPath=$dirPath;
}
// get directory path
public function getPath(){
if($this->dirProcessor==NULL){
$this->createDirectoryProcessor();
}
return $this->dirProcessor->getPath();
}
// get size of directory entries
public function getSize(){
if($this->dirProcessor==NULL){
$this->createDirectoryProcessor();
}
return $this->dirProcessor->getSize();
}
// get names of directory entries
public function getFileNames(){
if($this->dirProcessor==NULL){
$this->createDirectoryProcessor();
}
return $this->dirProcessor->getFileNames();
}
// get timestamps of directory entries
public function getTimeStamps(){
if($this->dirProcessor==NULL){
$this->createDirectoryProcessor();
}
return $this->dirProcessor->getTimeStamps();
}
// get last-access timestamps of directory entries
public function getLastTimeStamps(){
if($this->dirProcessor==NULL){
$this->createDirectoryProcessor();
}
return $this->dirProcessor->getLastTimeStamps();
}
// get last access timestamps of inodes
public function getInodeLastTimeStamps(){
if($this->dirProcessor==NULL){
$this->createDirectoryProcessor();
}
return $this->dirProcessor->getInodeLastTimeStamps();
}
// instantiate dirProcessor object
private function createDirectoryProcessor(){
$dirObj=new DirectoryProcessor($this->dirPath);
$this->dirProcessor=$dirObj->getDirectoryProcessor();
}
}
As you can see above, now the proxy class is capable of performing all the additional tasks that I discussed a few lines before, since I included some extra methods. Most of them deal with different types of timestamps. Besides, you'll realize that there's a new method called the "createDirectoryProcessor()" object, which is tasked with returning to calling code a directory processor object. That was easy, wasn't it?
All right, at this stage, the previously defined proxy class possess some decent functionality. This functionality is logically provided by a directory processor object, according to the definition for the proxy pattern. So what's the next step? Naturally, the next thing that I'm going to do is show you the signature for the pertinent directory processor class, in this way getting the pattern's schema completed.
To learn how this new directory processor class will be created, please click on the link shown below and keep reading.
Next: Completing the proxy pattern >>
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