1Z0-815 book as only study guide for the exam

[Darko Stojanovski]

Hi Jeanne Boyarsky & Scott Selikoff.

I am new to Java, but not at programing, as I program in Cobol for a long time. As Java and Cobol in big companies go hand by hand, I wanted to learn Java, get certified so I selected your book for 1Z0-808, from the great reviews and my colleagues recommendation to have a head start untill new 815 book is published.
I find the book very well organized and logically explained so that the beginners can understand. But when I tried some Whizlabs free tests, I find out that in some topics details are missing or I think they are missing :-)

For ex. acording to the book page 23, "You can add underscores anywhere except at the beginning of a literal, the end of a literal, right before a decimal point, or right after a decimal point." , the question 2 from the Whizlabs "float f4 = 12.345_F;" should be correct, but its not, because _ can not be put before F or L also.

Third question from Whizlabs, is asking about Arrays.fill , but that function is not in the book (or maybe it shouldn't be and the test is asking something out of scope the exam) etc.

So, my question is, is the book meant as a complete guide for beginners like me? How do I make sure that I study all the material that I need for the exam?

Thank you in advance

Kind Regards

[Sander Hollaar]

"float f4 = 12.345_F;"

I'd say the literal ends before the 'F', which makes the underscore be a the end of the literal, which is not allowed.

[Campbell Ritchie]

Welcome to the Ranch

Have you tried the code? My JShell didn't like it:-

float f = 12.345_f;
|  Error:
|  illegal underscore
|  float f = 12.345_f;
|                  ^

jshell>  

I would have thought that Arrays#fill() is something basic you ought to know about anyway.

[Darko Stojanovski]

Thanks for the answers guys.

I now know that is not correct, what I am trying to say is that for someone new to Java (like me for ex :-), reading the book and the explanation, then going thru the chapters Review Questions and thinking that you understand it, it was strange to see the question in the Whizlabs, as there was nothing similar mentioned before.

In reality, it's more like "Underscores are allowed in numeric literals only between digits. This means that you cannot use underscores in the beginning or the end of the numeral literal, right before a decimal point, or right after a decimal point. You cannot use it with prefixes such as 0x or 0b and suffixes as L and F."

Also, your remark about "Arrays.fill is something basic" is actualy answering my first question, are the exam books a complete guide to for learning for the exam. It seems they are not. But on the other hand, we have Head First Java book in the office and Arrays.fill is also not mentioned.

[Sander Hollaar]

In reality, it's more like "Underscores are allowed in numeric literals only between digits

Not true I'm affraid, this compiles:

int number = 0xA_AA;

[Scott Selikoff]

Yes, it is absolutely meant as a complete guide for taking the exam.  If you don’t know Java or programming at all, though, you may want to start with something else.

For material, it’s not uncommon to see material that may or may not be in scope in study material or practice software.  There’s a number of reasons for it.  Oracle is free to modify the exam at any time, so it’s possible they changed what is in scope.  They can even modify objectives, although this is less common.  They can even put “beta questions” in the exam that are unscored (do not contribute to your score).

They can also purposely put out of scope material, when in fact they are testing you on something else.  For example, maybe Arrays.fill() is out of scope, but the question is really about knowing whether you can modify a final variable.  Keep an eye out for things like this!

Finally, material is sometimes released too quickly (everyone wants to be first!) and may include topics from previous java 7/8 exams that is no longer in scope.  I know when the 1Z0-815 exam first came out there was a lot of debate and confusion among providers about this.  Jeanne and I have thought very carefully (and had many debates) about what is and is not in scope.

The best advice I can offer you is this... assume at least one thing on the exam will surprise you but that it probably won’t matter.  My apologies to those who have failed by one point, but most people score with some buffer.  Of course nothing is stopping you from learning out of scope material.  We often include valuable things that we know are out of scope as side bars in our books.

[Darko Stojanovski]

Thank you Scott for the detailed answer.

I will definitely read some more "Java for beginners" stuff and hopefully together with your books pass the exam.

[Paul Anilprem]

The exam objectives published by Oracle do not list every topic in detail. This poses a serious problem for content authors to keep the content aligned very closely with what is asked in the exam. In fact, the exam objectives of the OCP Java 11 exams are even more coarse grained than the previous version. They have omitted several topics that they mentioned explicitly in the objectives of the Java 8 exams. Since no one except Oracle knows exactly what all is covered, it is not really possible to provide exact i.e. nothing more and nothing less type of coverage of the exam.

Online mock exams and Print On Demand books that have a faster update cycle have an advantage here because they can modify content as and when information about the exam becomes available.

Scott Selikoff wrote:
The best advice I can offer you is this... assume at least one thing on the exam will surprise you but that it probably won’t matter.  My apologies to those who have failed by one point, but most people score with some buffer.  Of course nothing is stopping you from learning out of scope material.  We often include valuable things that we know are out of scope as side bars in our books.

This is definitely good advice. Having spent considerable amount of time here on coderanch, I have observed that some readers get very disturbed by seeing even a tiny bit of content that is seemingly out of scope. But better to know more than less, right?  

[Campbell Ritchie]

The material isn't out of scope, but only off the syllabus for the exam. That is something different. The exam has to have a syllabus and that has to be restricted otherwise there might be complaints and legal challenges to the exam. The full scope of knowledge about programming in Java® is however virtually infinite. Scott and Paul are right: it is, “better to know more than less.”

[Darko Stojanovski]

Thank you Paul and Campbell for the advices.

I will definitely study to LEARN Java, not just to pass the exam.

[Campbell Ritchie]

Darko Stojanovski wrote:Thank you . . .

That's a pleasure

Remember that many of the questions in the exam present you with bad code, whereas learning to program requires you to write good code.