Jayaraman Suresh Babu

Hi javaranchers,

I have been a somewhat silent member of Javaranch and been following the threads for a long time now. After a long procrastination (9 months after I got SCJA voucher), I finally decided time's up and started preparing two weeks ago. Today I cleared the exam with 100%. No answers were wrong.

Thanks very much java ranchers for creating such a wonderful website for the Java Community.

I will briefly post my experience below and also give some useful pointer and include a list of bookmarks that I used for preparing for the Exam. I did not study with anybook I collected online articles and studied online Java Tutorials from Sun and the UML Book pdf that is well know in this forum. These are more than enough to pass the exam with breeze.

My exam experience:
I finished the exam in 35 minutes including a review of all my answers. Most questions are easy. The only tricky (note: not tough) ones were in Java implementation of OO concepts. The questions were very tricky (for example they give class implementations and ask what results occur on compilation etc.)

I got approximately,

1. 12 questions on Java implementing OO
2. 10 Questions on Client /Server tecnologies
3. 7 Questions on general OOPs.
4. 5 Questions on UML
5. 3 Question on Algorithms including loops etc.
6. 5 Questions on rest of the topics in the syllabus such as swing, J2me etc.

Most people will easily answer all the J2ME, EJB, Client Server questions since they are straight forward. Just pay attention to Java/OO such as static methods, abstract class, inheritance etc since they are not straight forward and tricky.

I would say this exam is just too easy to pass i.e. get 68%. The trick lies in getting higher marks if aspire that.

best of luck to all.
Regards,
Jayaraman

P.S. You can download my SCJA bookmarks which I used for preparation here:

https://mspace.utep.edu/jsuresh/jay_scja.htm

I think thats wrong. Private members are fully accessible to all methods inside the class. However they simply not visible anywhere else.

Hi Brian,

Here are my answers to your questions:

You are calling an explicitly-defined no-arg constructor in the superclass. - No, I did not define any constructor in my subclass or superclass

You are calling the implicit no-arg constructor created for the super class because it has no explicit constructors.

You are calling a constructor in the super class that takes one or more args. - No, I did not define any constructor in my subclass or superclass

So then the second bullet ought to be happening. However, when you say it is taking the "implicit no-arg, constructor (default??) of super class" where is this coming from? If I am understanding right, its from the parent above it (which is Object? correct?), i.e. the grand father of my sub-class right?

Sorry If I am not getting this. But your answer is making me think again

Thanks

There are just too many of them. However, I find java.sun.com tutorials to be most concise if you already are familiar with programming. Otherwise, use a book such as "Head First Java"

Ilga,

But I think I understand why: probably it did not complain because it would have used the no-arg constructor of the Object class, the parent of my super class.

Thanks.

Ilga,

I agree with your first point. The compiler will call the default constructor which in turn will call the no-arg constructor of super-class. Howver look at the last line below. Here is the excerpt copied from Sun's Tutorial Page:

---------------
You don't have to provide any constructors for your class, but you must be careful when doing this. The compiler automatically provides a no-argument, default constructor for any class without constructors. This default constructor will call the no-argument constructor of the superclass. In this situation, the compiler will complain if the superclass doesn't have a no-argument constructor so you must verify that it does
---------------------------

Please read the last line. Even if the super-class's no-arg constructor was missing, the compiler did not complain.

Thank you Guys for your response

Hi Fred,

That really cleared things up. Thank you very much.

- Jayaraman

Hi,

I just was reading SunJava tutorial for refreshing and a few questions came to my mind.

Before I post my questions, let me give a you an excerpt from the Sun Java tutorial (from their website) on which my questions are based upon. In the Language basics chapter, Sun says that every class implicitly extends the Object class (i.e. Object is the superclass of everyclass) - agreed. Also, the tutorial says that in general when one class extends a parent class, if the subclass does not provide a default constructor, when instantiating an object of the subclass, the compiler will check and use the default no-arg constructor of its superclass. They have also mentioned that assuming one does not define a default constructor in the subclass, the compiler will verify and complain if its superclass also does not have default constructor.

Now here are my questions:

1. I defined two simple classes and inherited one class from the other. First I declared a default constructor in the parent class and no constructor in the subclass. When I instantiated a sub-class object, as the tutorial said, the compiler printed out the statement inside parent classes's no-arg constructor. However, the second time I removed the constructor from the superclass as well and compiler. This time, contrary to what the tutorial says, the compiler did not complain and the program ran fine. So is the tutorial wrong here? In the second case, is the compiler calling the constructor of the Object class?

2. I know that a subclass can I have only one superclass i.e. I cannot extend more than one class. However, every class extends Object.class as well. This means that even if I have my own subclass extending my own parent class, since implicitly every class in Java also extends Object, does this contradict what the restriction of inheriting only one parent class?

Sorry if these questions are stupid. All of your insights are appreciated.

Thanks,
Jayaram

Hi Marx,

Can you also send your material to jayapoo@gmail.com. I am also preparing for the SCJA exam. Your help is greatly appreciated.

Thanks,
Jay Suresh

Hi,

I am interested in acquiring a certification in the J2ME path. However, my company insists that developers should also be good in UML design rather then just writing thousands of lines of code. I found from the curriculam that SCJA has some UML related topics. Is that a beginners version or covers it comprehensively all UML related issues?. So is SCJA worth for getting certfied in UML related issues in addition to the Java coding?

Thanks,
Jay