Java - Initialize a HashMap of HashMaps

Question

I am new to java and practicing by creating a simplistic NaiveBayes classifier. I am still new to object instantiation, and wonder what to do to initialize a HashMap of Has

Answer 1

You must create an object before using it via a reference variable. It doesn't matter how complex that object is. You aren't required to initialize it in the constructor, although that is the most common case. Depending on your needs, you might want to use "lazy initialization" instead.