Burk Hufnagel

Khalid A. Mughal wrote:Hi Charles,
Yes. You are right. It is a bummer.
But I guess that would be the case with any publication that had your notes and was updated by the publisher.

Ouch. Seems to me that they should at least keep the notes - you could remove anything that's no longer needed.  As for highlighting, minimally it could be kept for any text that hasn't been changed from the previous version. And if you had something highlighted that was changed, they could go back and see if the new part should be highlighted...  As a developer, that doesn't sound like a tough feature to add.

Simon Roberts wrote:The memorization issue depends on a) making it difficult for exam takers to take questions away with them (there are people who send candidates to these kinds of exams professionally for no purpose other than collecting a few questions verbatim--hopefully this is not happening as much as it used to, but who knows) and b) on cycling new questions into the pool. We used to do that pretty continuously, but I can't speak for Oracle on that topic.

I know that for the Sun exams, the pool was much larger than the number of questions on the exam, which encouraged people to actually study so they understood things and not try to just memorize answers.

Interesting question.  One of the advantages of having an eBook is that it could be updated faster and with less cost than a paper book. I'll be looking forward to the answer.

Simon,
Unfortunately, it seems that some certifications for other languages can be earned by getting an answer book and cramming for a couple of days. I haven't seen Oracle's version, but I know from experience that you actually had to learn a lot of things to pass the programmer exam. Based on the size of the new Programmer's Guide, it seems the new exam requires you to learn even more.  I wish there was a way to educate the managers that didn't depend on them already having certified developers to compare against. If you know of any, please let me know and I'll help spread the information.

Khalid,
As someone considering updating my Java certifications, I'm wondering if you have any ideas on how long someone should be prepared to study for the exam. I see that your book(s) are over 1,800 pages long and that seems rather daunting. I was a technical reviewer for a Java 5 certification book which was less than half the size, and it took several weeks so I'm thinking it'll be around two months or so. Does that seem right?

Also wondering how long it took you to write it.  I went to the book;'s website (https://www.mughal.no/jse17ocp/samples.html) and while skimming parts of Chapter 1, I noticed that in addition to teaching us about Java you're also helping people understand UML diagrams. I applaud you're work in making Java easier to understand and giving people examples of how to use UML effectively.

Thanks for your time,
Burk

Simon Roberts wrote:Studying for an exam is a great way to enhance your skills, effectiveness, and employability.  That's true, frankly, whether you pass or not, though one hopes you'd press through to success.

When looking at developer resumes, to determine whether or not to interview a candidate, I always interview people who are certified as a Java Programmer, or Java Developer.  As someone who had passed the Programmer and Developer exams for the Java 2 platform, I know that they had to have a good overall understanding of the language and the standard libraries.

Thanks for the information.  I had heard about OODA (and John Boyd) a long time ago but had never thought about using it as a way to teach something.  I'm putting together a 4-hour class on TDD and I think your suggestion will help make it a better class.

I believe that teaching something is a great way to learn more about it since I have to understand the *why* behind what I'm recommending. I find that teaching a topic means I have to look at it from multiple points of view. I've also found it helps to remember the issues I had when I was first learning it so that I can address those issues and make it easier for my "students" to succeed with it.

Thanks again,
Burk

Hello,
I'm curious bout your experience writing a Head First book. Did it change the way you think about Android and how to explain things in general?
I'm also wondering if this is a major update from the second edition?

Thanks,
Burk

I suspect it depends on what you mean by proficient.  Given that the book is 900+ pages long, it's going to take some time to go through it -- but you'll probably have a better understanding of Android, and how to write good apps for it, than you would with a different book.  Head First books tend to go deeper into a topic so you'll actually know what you're doing.

Just my two cents
Burk

Thank you! I'm looking forward to reading it.
Special thanks to the authors for their help with my performance issues. I'm still working on it, but your advice has helped me in making headway.

D & D,

Another newbie question -- I'm working on an inherited (from another developer) browser app that has a data entry form that can be used to either create a new request or edit an existing one. It uses the antd library for the various fields and I've been asked to modify the code so that when the user is editing an existing request, the Save button is disabled unless one or more of the fields has been changed.  This makes sense but I'm concerned about keeping track of whether or not anything has changed.  When the user is editing an existing request, I have access to the original data returned by a web service, so I could make use of each field's onChange method and compare it's current value with the original, but I'm hoping there's a better way. Any suggestions?

Thanks,
Burk

I'll definitely look into the testing library and profiler.

In the meantime, I found that several of the components had another class declared in the same file, but outside of the component, and it was the same code copy/pasted into those files. So, I created a separate file for it and imported it instead. The class constructors are still being called multiple times, but it did reduce the overall codebase size and means I only have to make changes in one place if there's an error in that code.

The other thing I found is that even though the constructors are called multiple times, the class methods that call external web services are only being called once. It's like it creates an instance and starts to use it, but keeps creating copies that remain unused, until the component gets the data it needs so it can be rendered. Does that make any sense to you?

Thanks in advance,
Burk

I'm relatively new to React and the application that's having issues, but I can tell you that App does not declare any components within itself. This is a web app using the antd library so App sets up the basic layout of the pate. It imports several classes like Header, Footer, Sider, and Content then declares an onCollapse method to open or close the Sider (which contains a menu) and ends with the return method that sets up the layout for the page.

Looking at the console log, I can see that when I select some of the pages from the menu the constructor only runs once, but on others, it runs multiple times. I'll check the code to see if the pages where it runs multiple times contain other class definitions.

Thanks for the info - it may help solve this mystery and improve the app's performance,
Burk

Hello David and Dawn,
I'm working on an inherited React application that's behaving oddly, and I'm hoping you can help me with it. When the app runs, it seems to call the constructor for each object three times. I'm new to React, so I did some research and found references to StrictMode -- and sure enough, the index.tsx file had the same code I see in your book:
ReactDOM.render(  <React.StrictMode>    <App />  </React.StrictMode>,  document.getElementById('root') )
So I removed the React.StrictMode tag around the <App/> tag, and rebuilt the app, but it still calls constructors three times. I searched the code and don't see any other places where React.StrictMode is being used so I'm wondering if there's anything else that might cause this kind of behavior?

Thanks for any help you can offer on this,
Burk

Mark,
This looks like a very interesting book. Is there anything in it that is specifically for programmers or software architects, or addresses a problem we tend to have?

Thanks,
Burk