Hello can anyone answer this questi

[Dilenger4]

Hello can anyone answer this question for me.
Ive been looking over this block of code below.


They say that the class defines a method not a constructor since it has a return value. The method happens to have the same name as the class but that is irrelevant.

So i have one question.

1.)If the method happens to have the same name as the class and it is returning a value then this should result in a complation error. How can this not.

Thanks.




public class MyClass{
long var;

public void MyClass(long param){var = param;}

public static void main(String[] args){
MyClass a,b;
a = new MyClass();
b = new MyClass(5);
}
}

 

[Swamphen]

First:

the reserved word "new" in front of a name as in
"new MyClass()" will cause the compiler to look for a constructor with the same name and the same amount and type of parameters (aka the same syntax).

A constructor should always be declared as:
public Constructorname (parameters) { code }

So, in your code you have for instance "a = new MyClass()", but you don't have a constructor MyClass, since you put the reserved word "void" in front of the constructorname.

Second:

Normally a methodname should begin with a small letter and a class- and constructorname with a capital letter. And normally you wouldn't name a method the same way as your constructor. But there is no hard rule that you can't do it.
So, your declaration "public void MyClass(...) {...}" gives raise to a method named MyClass. And this will not give a compilation error, since it is perfectly legal. But, you obviously should consult the method by giving a message like "MyClass(5)" and not by "a = new MyClass(5)".

Hope this helped.

Swamphen

 

[Dilenger4]

Thanks for the help. This was one of those trick questions that they try and give you on the Java Programmer Exam. =C)