Does It Make Sense to Mark a Static Class as Final in PHP?

While it is technically possible to mark a static class as final in PHP, it is not considered a common or meaningful practice:

final class MyClass
{
  public static function foo(): string
  {
    return 'bar';
  }

  public static function baz(): string
  {
    return 'qux';
  }
}

Marking static classes as final in such a way does not serve any functional purpose because:

1. Static classes are not designed to be instantiated or extended, and;
2. Static classes are implicitly final by nature.

In PHP, static classes are typically used to group related utility functions or methods together without the need for object instantiation. If you specify the final keyword on a static class, it may give the impression that the class is meant to be extended, which can be misleading and unnecessary.

If you find yourself wanting to extend a static class solely to make its static methods available for use, it is worth questioning the design decision. This approach suggests a potential design flaw or a misunderstanding of the language features.

Instead of extending a static class, a better approach would be to define the static methods separately, in a utility class or namespace, and access them directly without the need for inheritance:

StaticClass::method();

By separating the static methods into their own utility class or namespace, it becomes more apparent that they are standalone functions or methods designed to be accessed directly. This helps maintain clarity and avoids confusion regarding the intended use of the classes, and promotes better code organization, usability, and ease of maintenance.