PHP 7 New Features

  • Scalar type hints
  • Return type declarations
  • Anonymous classes
  • The Closure::call() method
  • Generator delegation
  • Generator return expressions
  • The null coalesce operator
  • The space ship operator
  • Throwables
  • Level support for the dirname() function
  • The Integer division function
  • Uniform variable syntax

Public interfaces

A public interface is a set of code that third-party developers can call, implement, or build as a plug-in. Magento guarantees that this code will not change in subsequent releases without a major version change.

Public interfaces for a module are marked with @api annotation.

Install PHP 7 Centos 7

Run the following command s in the given order

yum -y update

yum -y install epel-release

yum install -y

yum -y update

yum -y install php71u php71u-pdo php71u-mysqlnd php71u-opcache php71u-xml php71u-mcrypt php71u-gd php71u-devel php71u-mysql php71u-intl php71u-mbstring php71u-bcmath php71u-json php71u-iconv php71u-soap php71u-fpm  php71u-cli 

service httpd restart

php -v

Serializing Objects

o Functions: serialize() / unserialize()

o Magic method __sleep() is executed with serialization, if available o allows you to specify which properties should be stored (serialized) and which should not be stored

o Can also create/change properties for serialization

o Magic method __wakeup() is executed with deserialization, if available ex: to open a database connection unique to the object


Object cloning is creating a copy of an object. An object copy is created by using the clone keyword and the __clone() method cannot be called directly. In PHP, cloning an object is doing a shallow copy and not a deep copy. Meaning, the contained objects of the copied objects are not copied. If you wish for a deep copy, then you need to define the __clone() method.

When an object is cloned, PHP 5 will perform a shallow copy of all of the object’s properties. Any properties that are references to other variables will remain references.

Once the cloning is complete, if a __clone() method is defined, then the newly created object’s __clone() method will be called, to allow any necessary properties that need to be changed.

 class Customer {
 private $name;
 public function setName($name) {
 $this->name = $name;
 public function getName() {
 return $this->name;
 public function __clone() {
 $c = new Customer();
 return $c;
 $c1 = new Customer();
 $c2 = clone $c1;

 echo $c1->getName()."\n";
 echo $c2->getName()."\n";


Way of storing data in a browser to id / track a user . Create (set) cookies with the setcookie() or setrawcookie() function and It must be called before sending any output to browser .

It can delay script output using output buffering, to allow time to decide to set cookies or send headers

Setcookie() params are defined according to specifications:

  • $name=value string
  • $value=value string
  • $expire=date optional; default is session end
  • $path=path specifies urls in a domain for which cookie is valid
  • $domain=domain_name check on domain attributes of cookies against host internet domain name
  • $secure cookie only transmitted via secure channels (https); boolean
  • $httponly cookie only made accessible via http protocol, not javascript; boolean

Access with $_cookie or $_request superglobals . Cookie data from the client is automatically sent to $_cookie, if params of variables_order() include “c” (environment/get/post/cookie/server) . It will overwrite itself if name, path, domain, secure, and http_only are identical .

Cookies are part of the http header o as with sessions, multiple values can be assigned to an array and To assign all values to only one cookie, can use serialize() or implode() with first value