Question

If I create an instance of a class in Java, why is it preferable to call a static method of that same class statically, rather than using this.method()?

I get a warning from Eclipse when I try to call static method staticMethod() from within the custom class’s constructor via this.staticMethod().

public MyClass() { this.staticMethod(); }

vs

public MyClass() { MyClass.staticMethod(); }

Can anyone explain why this is a bad thing to do? It seems to me like the compiler should already have allocated an instance of the object, so statically allocating memory would be unneeded overhead.

EDIT:

The gist of what I’m hearing is that this is bad practice mainly because of readability, and understandably so. What I was really trying to ask (albeit not very clearly) was what differences there are at ‘compilation’, if any, between calling MyClass.staticMethod() or this.staticMethod().

Answer 1

MyClass.staticMethod() makes it clear that you are calling a static (non-overrideable) method.

this.staticMethod() misleads the reader into thinking that it is an instance method.

staticMethod() is also on the misleading side (though I normally do it that way).

If you think of people reading your code as unfamiliar with it you tend to try to make the code clearer, and this is a case where the code is clearer by having ClassName.method instead of instance.method.