Can php have private static methods?

php can private static methods. Static private methods provide a way to hide static code from outside the class; this can be useful if several different methods (static or non-static) need to use it, i.e. code reuse.

The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer

I understand that static means that an object does not need to be Instantiation makes this property/method available. I also understand that this applies to private properties and methods as well as public methods. What I want to know is what static private functions can benefit you from. For example:

class Beer {
    static private $beertype = "IPA";
    private function getBeerType() {
            return self::$beertype;
    }
    static public function BeerInfo() {
            return self::getBeerType();
    }
}
print Beer::BeerInfo() . "\n";

As long as getBeerType() is called from the static public method, the private method will execute fine without instantiating the object. If a static public method has access to all private methods (static and non-static), what is the benefit of declaring a method static private?

With strict error reporting turned on, I do get the warning that I should make getBeerType() static, although it still allows me to run the code. I did some research and it seems that other languages ​​(Java) will force you to declare a private method as static when a static public method is called. Looks like PHP lets you get away with this. Is there a way to force it to throw an error and not execute?

Static private methods provide a way to hide static code from outside the class. This may be useful if several different methods (static or non-static) need to use it, i.e. code reuse.

Static methods and static variables (sometimes called class methods and class variables) are a way of putting code and data into a namespace. You can also think of class variables as variables attached to the class itself, of which (by definition) there is only one, as opposed to instances of the class, of which there may be zero, one, or more. Class methods and class variables can be used to work with properties that not only remain the same across all instances but are actually the same.

An example of a class variable is a database handler in an ORM entity object. All instances are their own objects, but they all need access to the same database handler to load and save themselves.

Private vs. public is an entirely separate quality, I doubt you're stumbling over something. Private methods cannot be called and private variables cannot be accessed from code outside the class. Private methods are typically used to implement "internal" logic on an object that is not accessible outside the object. This restriction can be achieved through instance methods and class methods.

An example of a private class method could be a factory method. There may be three factory calls to create objects that may differ in terms of the arguments provided. But most of the operations are the same. So it goes into the private static method called by the non-private factory method.

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