Why to Call super()

Suppose I have a class named Class1. Another class extends Class2 which extends Class1.
class Class1{
Class1(){
class Class2 extends Class1{
Class21(){
super()//Why this.. Any way, super constructor is being called no??
We sometimes call super() in the constructor of the sub class to invoke the Super Class constructor. Now, my question is, Whenever we make a new instance of a class, it is any way going to call the super class constructor as per the basic Java design. Then Why, we sometimes call super() specifically.. ???
Thanx in Advance..
Naren

When java calls the super class constructor, it calls the no argument
constructor.One reason to call the constructor is if the class was
designed without a no argument constructor. You would get an error
if you extended it and didn't call its constructor.You may also want to
call a different constructor instead of the default one.

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Is there a pattern to accomplish the following?
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class AClass {
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AClass(){
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interface Setuper {
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paul.miner wrote:
jtahlborn wrote:
this is a very bad design. a class should never call a method in its constructor which can be overridden in a subclass. the behavior in this situation is "undefined" according to the JLS, and should be avoided at all costs.I agree this is bad design, but I don't think the behavior is undefined. I think the behavior is that the subclass method will see that subclass' fields in their uninitialized state, which do have defined values (int's are 0, booleans are false, references are null, etc). Are you sure this is in the JLS?you're right, i went back and looked at the JLS (12.5 in the third edition for those following along at home). method dispatch is specified to work consistently during constructor invocations (for some reason i remember it being undefined). regardless (we both agree here), it is a terrible design, because the subclasses methods are being executed before that class is initialized.

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