In static classes don't use constructors. So each static method should fulfill check its dependencies, and the calling code needs to initialize all the parameters of the method, if you do not use the default values.
the calling code needs to initialize all the parameters of the method
$a = $this->var;
1. If the class has a static method the class can't be designer?
2. What kind of dependency is it? You can transfer everything you need
Inside of a static class you cannot refer to a class property? For example, $a = $this->var;
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