You get this error because a class which has no constructor has a default constructor, which is argument-less and is equivalent to the following code:
public ACSubClass() {
super();
}
However since your BaseClass declares a constructor (and therefore doesn’t have the default, no-arg constructor that the compiler would otherwise provide) this is illegal – a class that extends BaseClass can’t call super(); because there is not a no-argument constructor in BaseClass.
This is probably a little counter-intuitive because you might think that a subclass automatically has any constructor that the base class has.
The simplest way around this is for the base class to not declare a constructor (and thus have the default, no-arg constructor) or have a declared no-arg constructor (either by itself or alongside any other constructors). But often this approach can’t be applied – because you need whatever arguments are being passed into the constructor to construct a legit instance of the class.