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doubt in constructor...

Ganeshkumar cheekati
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Joined: Oct 13, 2008
Posts: 362
SOURCE:www.javabeat.net

It is giving compilation error as
can not find symbol Base()
In Base class´┐Ż..
Here I am calling long parameterized constructor in Test2l class only..
But why this error?
Can anyone explain me?



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Seetharaman Venkatasamy
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Joined: Jan 28, 2008
Posts: 5575

compiler calls super() inside the Test2l() constructor implicitly. so,it calls Base() which is not there
Aditya Keyal
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Joined: Dec 01, 2008
Posts: 71
In any derived class if you have a constructor it MUST explicitly call some constructor of the parent class.
If you do not specify then it looks for the default constructor of the Base class.
In your case the default constructor of the Test2 class does not explicitly call the parameterized constructor of the Base class.
Thus the compiler searches for the default which it cannot find and thus the error. Try removing the default constructor or alternatively calling the parameterized constructor from the default. It will work


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Ganeshkumar cheekati
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Joined: Oct 13, 2008
Posts: 362
but here it is invoking parameterized constructor in Test2l i.e Test2l(long)

by using new Test2l(2);

why should it go for default constructor in Test2l?

Ganeshkumar cheekati
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Joined: Oct 13, 2008
Posts: 362
the compiler add super(); implicitly so it search for default constructor in Base class which is not available
thats why it is showing error..

it doesnot matter which constructor we are invoking we must satisfy compile rules...

am i right?
James Tharakan
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Joined: Aug 29, 2008
Posts: 580

Yes you are right..


SCJP 6
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Vinay Dinakar
Greenhorn

Joined: Dec 30, 2008
Posts: 17
compiler look for default constructor of base class because you used this code .

Test2l()
{
}


remove above line and it will compile properly.


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Bear Bibeault
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"vinay ds", please check your private messages for an important administrative matter.


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Punit Singh
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Joined: Oct 16, 2008
Posts: 952
If you do not call explicitly super(...) from your constructor, then only compiler will add super().

for your code compiler is adding super() in second constructor.


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