#SingletonClass

Phuture\Coherence\Support\SingletonClass

abstract class SingletonClass

Singleton base class that ensures only one instance of a class exists throughout the application lifecycle.

This class implements the Singleton design pattern, which restricts the instantiation of a class to a single instance and provides global access to that instance. The pattern works by:

• Making the constructor private to prevent direct instantiation
• Preventing cloning via a private __clone() method
• Preventing unserialization via __wakeup() to avoid creating duplicate instances
• Providing a static getInstance() method that returns the single instance

Important: Use this pattern only when strictly necessary. The Singleton pattern can make code harder to test and maintain due to hidden dependencies and global state. In most cases, a Dependency Injection container is the recommended approach as it provides better testability, flexibility, and follows SOLID principles.

Example:

 1namespace Phuture\Coherence;
 2
 3use Phuture\Coherence\Class\SingletonClass;
 4
 5class MyService extends SingletonClass
 6{
 7    public function doSomething() { ... }
 8}
 9
10$service = MyService::getInstance();

#Methods

#__construct()

protected function __construct()

Class is singleton and cannot be instantiated directly.

#__call()

public function __call(string $name, array $arguments): void

Handle calls to undefined instance methods.

Throws

• MemberAccessException — If the called method does not exist on the class

#__callStatic()

public static function __callStatic(string $name, array $arguments): void

Handle calls to undefined static methods.

Throws

• MemberAccessException — If the called static method does not exist on the class

#__clone()

private function __clone()

Class is singleton and cannot be cloned.

#__serialize()

public function __serialize()

Class is singleton and cannot be serialized.

#__unserialize()

public function __unserialize(array $data)

Class is singleton and cannot be unserialized.

#getInstance()

public static function getInstance(): self

This static method controls the access to the singleton class. On the first run, it creates a singleton instance and places it into a private static field. On subsequent runs, it returns the existing instance previously stored in the static field.

Returns self — A single instance of the current class