General Java Questions II

constructors methods NOBODY will quote it as an authority.

How can so many people call constructors methods if they aren t.

Okay. Are they or aren t they? I holding to the definition that they are not unless it is

so common to call them that, that I will have to change.

Comments?

Answer: If you go by the JLS (Java Language Specification) and the Java API (and

you should) , then no, constructors are not methods. Consider that

Class.getMethods() returns an array of Method instances and

Class.getConstructors() returns an array of Constructor instances, and Constructor

and Method or not interchangeable (one is not derived from the other), but both

implement the Member interface. Seems to me that Java is going out of its way to

differentiate them.

Besides, the mechanics of constructors are so different from the mechanics of

methods, there seems to be no value to considering one a member of the set of the

other.

Now, as far as teaching the language goes:

Methods:

+ return types

+ called by name

+ executed multiple times

Constructors:

+ super(...) or this(...) as first instructor (often implicit)

  everything else

I very much do not like trying to lump the two concepts together, especially in

introductory courses. Conceptually they are very, very different things.

A constructor is a unique element (even if there are several). It has the name of the

class, its declaration is different, and it doesn t have the same syntax as a method. It

plays a unique role. You can call a method from a constructor, but you cannot call a

constructor from a method.

I say constructors are distinct from methods, and for students, blurring the distinction

will lead to problems.

by Chuck McCorvey, Chris Wolfe, Paul Lutus

 Q: Simple question: why constructor doesn t work in following example?

class Start { 

   public void Start() { 

      System.out.println("Konstruktor START"); 

   } 

} 

public class Test { 

   public static void main(String[] args) {

      Start s = new Start(); 

   } 

}

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