Today I have an interesting topic related to object oriented programming concept in php for you all. Many of us may be wondering “What is exactly design patterns and how to use it in our application?” Design patterns are architecture of programming which will help developers to understand, update and extend the code easily. Shortly we can say design patterns are solution of the different problems of application. There are various design patterns available, today let me explain what is singleton design pattern exactly and how to use it in your application.
What is singleton design pattern?
Singleton
pattern which doesn’t allow system to create more than one instance of the
class. Generally creating object will allocate some memory space. So creating
multiple object for each class will take unnecessary more memory space and slow
down your application, which can be avoided using singleton pattern. We can say
like it is an object oriented principle which will allow you to create better
architectural program and can boost up performance also.
For
example -
Class DB
{
public function __construct()
{
…………….
}
public function connection()
{
……………..
}
public function query()
{
……………..
}
}
$db = new DB();
$db->connection();
$db->query();
In above example each
time you try to connect with database it will create new object of the class
and creating new connection which will allocate unnecessary more memory unintentionally.
How to use singleton
design pattern?
Let see how can we solve above common problem with singleton design pattern –
Class DB
{
private static
$instance = NULL;
private function
__construct() {………. }
public function
connection(){…………}
public function
query() { …………. }
public static function get_instance()
{
if(is_null(self::$instance)) {
self::$instance = new DB();
}
return self::$instance;
}
}
In this
above example get_instance() method will create single instance of the class
only if property is null else it will return the existing instance of the
class.
For
example singleton pattern -
$dbobj
= DB::get_instance();
$dbobj->query();
Like
this we can overcome from creating unnecessary memory space and use existing
object of class if exists already. Conclusion we can say singleton pattern is
allowing us to limiting to create number of object for same class, and it is
really easy to use.
Hope you
all understand the concept now and enjoying my posts. Please visit for my new
post, soon I am going to bring up some new applications and libraries which
will make your work simple.
You can also join my technical groups and stay updated, You can simply click on the follow us links below-
