Constructors.

[Ritu Kapoor]

Query: What is the use of declaring a constructor as protected, when we know that the constructors are not inherited.

[Pradeep bhatt]

Protected constuctors can be called by subclasses and also classes within the same package.

[agrah upadhyay]

Although constructors are not inherited yet they aare called implicitly by run time system or explicitly by U

[Akhilesh Trivedi]

This seems tricky. Guess, if I have a "private" constructor and inherit a subclass from it. Now, when I would instantiate a sub-class sub-class constructor will be called which will in-turn call super class constructor, but is that accessible???

 
class Super
{
 private Super()
{
System.out.println("super");
}
}
 
class sub extends Super
{
public sub()
    {
System.out.println("hello");
}
 
}
public class someClass
{
public static void main(String arg[])
{
    sub s = new sub();
}
}

Shows error. Good... thank you all.

[A Kumar]

Hi,

As akhil had mentioned in his post...

We cannot instantiate the class with only private constructor..

Such class object can be created only in that same class...

So in the event of inheriting this class...you cannot instantiate an object of the sub class...since the base class constructor is not visible to the sub class..

If it is protected ....it is visible in any other class withing this package and any other class that extends this base class...

So we can instantiate an object of this sub class..

But if we want to instantiate an object of the base class elsewhere ...in a different package..it behaves as a private scope...whether you are extending that class or not...

In case you are extending...you can cannot create directly the base class.. instance...but you can create instance of the extended class.. in this extended class..


[ October 05, 2005: Message edited by: A Kumar ]

[Ritu Kapoor]

Thanks to kumar & Akhil.