Liutauras Vilda

Pass the test? Add your name to the wall, partner.

OCMJEA Wall of Fame [order by Date]
Version	Name	Final Exam Date	Part 1 Score	Assignment Score	Story	Assignment	What's Next	Country
JEE6	Mahmut Eren	October 19, 2018	76%	147/160	-	Quick Computer	-	Turkey
JEE6	Nataraj Basappa	September 26, 2018	73%	152/160	https://www.natarajmb.com/2018/09/journey-to-ocmjea/	Quick Computer	-	UK
JEE6	Mustapha SENHAJI	February 03, 2018	73%	142/160	-	Retire Early	AWS Solutions Architect	Morocco
JEE6	Gautam Deb	December 15, 2017	76%	156/160	-	Retire Early	-	India
JEE6	Ernest Barroso	November 02, 2017	78%	131/160	Two months on the 3 steps	Gemstone International	Spring Professional Certification	Venezuela
JEE6	Francesco Fabi	October 09, 2017	71%	148/160	-	Team Doctor	TOGAF	Italy
JEE6	Om Narayan Pandey	June 26, 2017	80%	156/160	-	Dream Car	-	India
JEE6	Samrat Roy	May 24, 2017	83%	155/160	https://coderanch.com/t/680789/certification/OCM-JEA-story	Gemstone International	-	India
JEE6	Sanjay Garothaya	May 01, 2017	80%	151/160	-	Team Doctor	-	USA
JEE6	Amine Ouali Alami	April 02, 2017	78%	156/160	-	Utility international	-	Morocco
JEE5	Rajesh Narayanan	Mar 17, 2017	92%	143/160	-	Team Doctor	-	India
JEE6	L. Witkowski	Mar 1, 2017	71%	140/160	-	Retire Early	-	Poland
JEE6	Rajesh Kumar Srivastava	Jan 24, 2017	73%	139/160	-	Utility International	Expertise in Machine Learning & AI	India
JEE6	Raghavendra Desoju	Jan 23, 2017	83%	149/160	-	Quick Computer	AWS Solutions Architect	USA
JEE6	Carlo Cangemi	December 23, 2016	88%	144/160	-	Dream Car	-	Italy
JEE6	K. Tsang	Dec 2, 2016	71%	-(JEE5 upgrade)	-	-	-	Hong Kong
JEE6	Sergio Navarro Garza	May 28, 2016	83%	149/160	-	Utility International	TOGAF	Spain
JEE6	Caio Bessa	May 19, 2016	71%	143/160	-	Retire Early	IELTS	Brazil
JEE6	Mithun M S	May 05, 2016	78%	141/160	Story	Wireless Phone Company	TOGAF	India
JEE6	Yogaraj Khanal	March 23, 2016	71%	138/160	-	Quick Computer	OSCP	Nepal
JEE6	Angelo Verdicchio	Feb 05, 2016	83%	148/160	-	Factory Homes	Improve design & architecture skills	Italy
JEE5	Sourav Biswas	Feb 17, 2016	93%	144/160	-	Retire Early	Improve design & architecture skills	Australia/India
JEE6	Siddhesh Jog	Jan 27, 2016	76%	146/160	-	Wireless Phone Company	Improve design & architecture skills	India
JEE6	Mika Kilpeläinen	Dec 7, 2015	P	P	-	Gusher Oil	HTML+CSS	Finland
JEE6	Vijay SN	Nov 28, 2015	86%	145/160 90%	-	Wireless Phone Company	Improve Architect Skills	India
JEE6	Efthymia Armanidi	June 2, 2015	71%	149/160 93%	-	Team Doctor	ITIL	Greece
JEE6	Rodrigo Cayres	Oct 19, 2015	81%	153/160 96%	-	Big Smokes Cigar Shop	OCEJEE6JSFD (JSF)	Brasil
JEE6	Vijaya Raghava	Sept 26, 2015	81%	143/160	-	Team Doctor	PMP, Hadoop	India
JEE6	Claudia Arévalo	Jun 25, 2015	88%	153/160	Story	Factory Homes	TOGAF	Colombia
JEE6	Heliton Rodrigues Aranha Filho	Apr-30-2015	73%	NA (JEE5 Upgrade)	http://www.coderanch.com/t/650230/java-Architect-OCMJEA/certification/Certified-OCMJEA-finally	NA (JEE5 Upgrade)	TBD	Brazil
JEE5	K. Tsang	Mar 4, 2015	89%	144/160	part1 part2/3	Quick Computer	-	Hong Kong
JEE6	Mike Degteariov	Mar-31-2015	78%	151/160	-	Team Doctor	Hadoop	Canada
JEE6	Bora Seven	Mar-12-2015	71%	140/160	Story	Big Smokes Cigar Shop	TOGAF9	Turkey
JEE5	Heliton Rodrigues Aranha Filho	Oct-18-2014	71%	141/160	http://www.coderanch.com/t/650230/java-Architect-OCMJEA/certification/Certified-OCMJEA-finally	Factory Homes	TBD	Brazil
JEE6	Rahul Sharesth	Sep-19-2014	83%	141/160	-	Dreamcar	TBD	India
JEE6	Mahavir Singh	Aug-10-2014	71%	140/160	-	Utility International	Improve Architect skills	India
JEE5	Anuj Sethi	Jul-1-2014	90%	141/160	-	Team Doctor	Improve architect skills	IRE
JEE6	Raffaele Sangiovanni	May-1-2014	80%	153/160	-	Wireless Phone Company	Scrum	ITA
JEE5	Pothiraj Marichamy	Mar-1-2014	95%	P	-	Team Doctor	TBD	USA
JEE5	Uma Monday	2014-02-28	95%	145/160	-	Gemstones International	TOGAF9	USA
JEE5	Sirish K Somanchi	2013-06-11	78%	152/160	-	Team Doctor	TOGAF9	India
JEE5	Marco Bresciani	2013-01-31	64%	134/160	-	Wireless Phone Company	Ruby and RoR	Italy
JEE5	Subrahmanyam BV	2012-12-15	89%	152/160	-	Team Doctor	-	India
JEE5	Sachin Dixit	08-Dec-2012	78%	144/160	-	Team Doctor	PMP	India
JEE5	Diego Lins de Freitas	11-October-2012	85%	140/160	-	Quick Computer	IEEE - CSDP	Brazil
JEE5	Juan Gonzalez del Pino	11-October-2012	P	P	Story	Gusher Oil	Not sure	Spain
JEE5	Chandra S Billanuka	15-July-2012	P	P	-	Wireless Phone Company	TBD	USA
JEE5	Chennakrishna R Gottam	29-July-2012	P	P	-	Gusher Oil	PEGA	USA
JEE5	Srinivasulu Kopparapo	06-July-2012	P	71%	"Here"	Gusher Oil	Java Enterprise Edition Certified Master	USA
JEE5	Sudha Sundar	18-Feb-2012	P	153/160	Here	Gusher Oil	Oracle IT Implementation Specialist, PMP	USA
JEE5	Neeraj Javiya	21-Jan-2012	P	P	Here	Team Doctor	TBD	USA
JEE5	Mahesh R. Desai	12-Dec-2011	P	P	-	NA (JEE5 Upgrade)	Oracle Linux Fundamentals, PMP	California, USA
JEE5	Sada Kurapati	22-Dec-2011	95%	146/160	Part I Story	Gusher Oil	TOGAF	USA
JEE5	Mahesh R. Desai	12-Dec-2011	P	P	-	NA (JEE5 Upgrade)	Oracle Linux Fundamentals, PMP	California, USA
JEE5	Eric Manuguerra	04-Oct-2011	85	P	-	Factory Homes	TBD	France
JEE5	Mayur Bodkhe	27-Sep-2011	P	143/160	-	Wireless Phone Company	TBD	UK
JEE5	Sankha S Pathak	27-Aug-2011	P	155/160	-	Wireless Phone Company	TOGAF	INDIA
JEE5	Vignesh Murali Natarajan	21-Aug-2011	100	P	-	Big Smokes Cigar Shop	PMP?	India
JEE5	M. A. Riveros T.	21-Aug-2011	P	P	-	Dreamcar	TBD	Colombia
JEE5	Jari Timonen	29-JUN-2011	P	P	Part1	Factory Homes	-	Finland
JEE5	Roxana Crisan	17-Jun-2011	93	P	-	Dreamcar	TBD	Romania
JEE5	Tan Chin Sheng	12-Jun-2011	96	P	-	Factory Homes	TOGAF9	Singapore
JEE5	Ashutosh Sharma	29-Mar-2011	P	P	Here	Big Smokes Cigar Shop	TOGAF9	USA
JEE5	Martin Zisler	19-Jan-2011	P	P	-	Gusher Oil	JEE6 Webservices	Switzerland
JEE5	Wolfgang Unger	21-Dec-2010	P	P	-	Big Smokes	Holiday in Brazil	Germany
JEE5	Jeanne Boyarsky	17-Nov-2010	87	P	Here	Factory Homes	TBD	USA
JEE5	Rupesh Kumar	17-Nov-2010	82	P	-	Dream Car	TBD	USA
JEE5	Sylvain Duchesne	12-Nov-2010	P	P	-	Dream Car	SCEA for Java EE6 - Upgrade	Canada
JEE 5	Ravi Iyer	21-Oct-2010	P	P	Story	Factory Homes	-	India
JEE5	Kuppusamy Venkatasubramanian	19-Jul-2010	85	P	Here	Dream Car	TBD	Singapore
JEE5	Varun Chopra	03-Mar-2010	96	P	Story	Factory Homes	TBD	-
JEE5	Jose Luis Iturbide	24-Apr-2009	71	P	Story	Factory Homes	Spring & Android	Mexico
J2EE	Gabriel Belingueres	30-Dec-2008	85	91	-	Fly By Night	-	-
J2EE	Stefan Meier	29-Dec-2008	89	77	Story	Fly By Night	SCEA5 Upgrade	-
J2EE	Mahesh R. Desai	12-Dec-2008	81	89	Story	Fly By Night	SCEA for Java EE6 - Upgrade	California, USA
J2EE	Paul Michael	5-Nov-2008	91	77	Story	Fly By Night	Flex or .Net	-
J2EE	Abhinav Srivastava	6-jul-2008	89	95	here	Fly By Night	-	-
J2EE	Ashish Sarin	15-Aug-2008	70	92	here	Fly By Night	TOGAF	-
J2EE	Patrick Williams	14-Nov-2007	85	87	Story	Fly By Night	SCJD & Upgrades	-

Other Java Certification Wall of Fames

SCJA Wall of Fame

SCJP Wall of Fame

SCJD Wall of Fame

SCBCD Wall of Fame

Please be aware of this.

Please be aware, that GitHub is experiencing problems (seem to be serious) over the day https://status.github.com/messages

Website isn't consistently accessible. Services don't get synchronised with other platforms. etc...

I see..

I had also few problems with system freeze. Mine problem was (at least I think and didn't experience again), that I used to use caffeine app to prevent computer going to sleep in any way (hdd sleep, screen sleep, etc.), so this app didn't work after system upgrade, so every time computer screen went to sleep, or screen saver went on, computer got frozen.

So what I did: turned off screen saver (don't need them), turned off hdd sleep after X minutes, turned off screen sleep after X minutes (anyway I liked always keep my mac with caffeine on) - and didn't experience any freeze again.

Anyway, you are right, but I'm expecting some update any time soon, so the issues would be addressed. This has been true with almost all releases of macOS. The difference is, that problems disappear after some time, while on MS Windows they grow like mushrooms after the rain, and unfortunately barely somebody picks them.

Sresh Rangi and Gerard Charles, will get back to you later... seeing some good comments

Piet Souris wrote:I also had a look at your code. My first impression is that I get a sense of over-desinging here and there, making things more complex than necessay. Perhaps it is the modern way of dong, I don't know, but for instance this Builder.build() looks a bit cumbersome.
...
About the RegenerationRules, why do you fix the 2 and the 3, given that the class is final? I had a similar class, with two fields: List<Integer> stayAlive and ditto: becomeAlive, that were parameters of my constructor.

Yes, probably it was over-designed here. It was really a wacky builder pattern implementation (with an idea to augment), which in turn served very little.

The thought behind that was, that I took some hypothetical future requirement of some extra rules let's say:
RegenerationRules.Builder rules = new RegenerationRules.Builder(); rules.withLivingNeighbors(..).withBrickWalls(..).withDragons(..)..And I thought I could let them change over the moment in time...
But since I did not attempt to implement non of these extra's, I most likely over-complicated without seeing obvious deficiencies and went down the wrong route. Yet more experiments to come. Thanks!

Piet Souris wrote:...determine the neighbors of a Location... but that method is not foolproof...

Good point, missed it. Thanks for the comments!

Piet Souris wrote:But please report your impressions at the GDCR with your code!

Indeed these were my goals to have some prior experiments done as my homework, so could have more productive time there after being fallen to few traps already!

salvin francis wrote:I looked at your code a bit more in-depth today and the following questions came to my mind :

Why can one not instantiate World ? The only way you are allowing is via a empty() method which generates according to a fixed SIZE of 10

Why is World square ? (as in number of rows=number of columns)

Well, one CAN instantiate world, and that is exactly through a method empty(). I think it is expressive and tells what one can expect from such a created world, meaning the world to be empty.
At this stage I did not concentrate much on such aspects as world's height, width, shape.. I might do care about them when I come to the moment of GUI need and in particular if I would want users to be able to set world size, but once again, at this stage my main goals were to experiment with design decisions, and so the different aspects of code could be tested throughout without exposing much/or at all of their internals, or in isolation if we can call it like that.

salvin francis wrote:
I see that you have implemented this as a fixed world with cells which are either Alive or Empty. The way I approached this was that I made an implementation which only kept Alive cells. There were no "Empty" cells.
Actually this is what fits in the real world philosophy too. In real life, we would observe a 'petri dish' with some cells. These cells would grow/die depending on various conditions, the 'petri dish' is their domain/world. With the implementation of "Empty" it looks like the world has some "slots" where a cell can reside or not.

Just food for thought

This your thought made me stop and think for a while. Sounds reasonable what you say. I see the way to avoid EMPTY and have only ALIVE, I'll try such approach as haven't tried yet. Thanks!


NOTE: (to those who follow)... The main reason of mine to start this project was/is to experiment with various designs implementing this game. I wouldn't say there is obviously good or obviously bad design(s). And I wanted to try some of these (designs) before I attend GDC event, so I would have some of my own prior experience in order to be more productive during the event.

First, pie slices to those who haven't got yet!!!

Some interesting points floating around, which in turn already allowed me to see some deficiencies with my current design. I need to absorb/experiment with each of these first.

But even now, I already can say a big thanks for your time and constructive criticism - I'll get back to each of you (salvin, Piet, Sresh), either late night today or other day once manage to spend some time on it.

In case somebody reads, one of my colleague here, Stephan, raised some concerns (behind the hood, within GitHub platform) regarding the topology, where I mixed up two different contexts Location and Direction into one - Location, and as a result represented directions where to move in order to find neighbours by reusing Location class (and that is bad), which actually represents an absolute path within a world map. So separated these lately and now there are Location and Direction (appear as an inner enum as it is needed just there for the moment).

Another point we discussed that I have an enum Cell which implements (/-ed actually) Mutable interface. And there he had a point. Enum is an immutable from Java's stand point, and to implement Mutable interface was a bit odd, even though the ideas underneath didn't clash much as simply two different domains interfered Java's (immutable enum) and automaton game (where cell mutates). As a result I renamed Mutable idea within the domain entirely, so it became:

Mutable -> Regenerable
Mutable.mutate() -> Regenerable.regenerate()
MutationRules -> RegenerationRules

And these make much more sense now. Thanks to him.

However, we still got an argument whether to represent Cell as an enum is a good idea. Maybe to have Cell as a regular class with an inner enum State ALIVE, ETC... would be better. I must say I had implemented that 2 days ago - well, more experiments to come.

It is very interesting little project to work on.

salvin francis wrote:I ran that program and it just printed a huge log of dots and zeros !!!
Even a simple JFrame with a single textarea would be great.

Yet again, first of all, thanks for reviewing it.

Yeah. Agree, it isn't user friendly and much interactive yet. But I have created for myself an enhancement item, so at some point will get it done.

However, at this stage my main goal was to come up with a design so it would be simple to understand, easy enough extend and very importantly to test. Tried to keep separate pieces responsible as much as their need to be responsible for, so changing something I wouldn't need to rewrite tests from scratch and similar. Interesting, but initially that was exactly my experience. Started with semi TDD, thought came up with a fairly nice approach, however, trapped to a situation, that I was not able to test everything without exposing objects internals as for instance Location class was relying on World's internal data structure to count alive neighbours around, and I did want to have minimum getters, minimum mutation... etc. So most of the time such figuring out design, but I'll have time for GUI, just my designer's skills aren't anywhere great.

salvin francis wrote:I am glad to see that your glider "wraps-around" the world.

Yep, since all action happens on an infinite grid, I was looking for the way to put this concept in place.

Thanks for comments.

salvin francis wrote:minor suggestions: Maybe World.SIZE could have an access modifier (probably public) ?

Nah Stephan some time ago suggested, and once again re-read Effective Java by Joshua Bloch, so basically I give visibility as much as it is needed and no more. On that point of view, I'd prefer that even interfaces would provide an ability to implement package-private methods, as sometimes (and I faced this situation too), I exposed method (meaning had to make public) without real need of that, i.e. Cell.mutate() is public, while perfectly could work with package-private visibility.

Jeanne Boyarsky wrote:In World, the indentation of this code misleads about what it does. Since the two forEach() statements are aligned, they imply that they are operating on the same stream.

First - thankful for a review and comments.

Agreed. Indentation was misleading. With streams kind of can get messy when always aligning by the dot ".". I simply now just let IDE to format for me based on by default pre-configured its rules.

Jeanne Boyarsky wrote:More importantly, calling map.put() in a forEach isn't good practice. Is there any reason you can't use a collector which would dispense with the inner forEach() entirely.

That's a good one! I was so concentrated on design, so got less than optimum at other points. Initially I simply had 2 habitual loops, so later decided to replace with forEach, hence got horrible blocks. Just refactored to use collectors you suggested in empty(); nextGeneration(); methods, indeed much better as it hides internals how data structure gets populated. However, a bit struggled until remembered how to do it with specific Map's implementation.

Jeanne Boyarsky wrote:I'm not a fan of the default method in Mutate. It feels like a hack since it isn't used for legacy code.

Well. I was researching about default before attempted to use it. To my disappointment, since Java moving towards modernising herself, I don't understand why default is so implied to be used only for legacy code. It is such a nice feature to have in my opinion (makes even slimmer gap between interface vs abstract class) and it fitted perfectly to my idea. Upon hypothetical requirements change mutable(s), i.e. Monster just need to implement that interface without providing any extras; and define their mutation rules. I'm not up (convinced yet) for removing it and implementing this method in the very same way in each and every concrete Mutable implementation.

Thanks for the comments once again!

Junilu Lacar wrote:If I had a collection of Book objects, would bookList.toArray(Book[]::new) be easier to read than bookList.toArray(new Book[0])?

With no doubts. new Book[0] is confusing as hell to me, because it gives an impression that it will create a 0 length array, and since we know arrays can't expand, it gives a feeling while Book[]::new suggests me that it will create an array of the needed size whatever that size might be, which in fact I don't need to know. That's how my brains interpret that.

Hello Ranchers,

For a long time I was fascinated about this project, but never attempted to implement it myself. That's changed.
So decided to create a personal construction site and work at it to practice and experiment with various design decisions implementing this cellular automaton.

For the past 3-4 days I wrote and re-wrote.. this project countless number of times (small portion of commits history recorded).
The version I have currently is something I think I could try to justify why I have it like that, and to what angle it has flexibility to offer so I chose to implement it that way.

However, do extra pairs of eyes see some illogical design decisions, or have tips what to think about how this could be improved further to avoid some potential limitations I could face when some hypothetical requirements change?

Don't get fooled by the width of the project (only very few source files), but it really taught me many lessons already, and I believe it will again.

From the very first versions I came up with, this recent version I think got shorter twice, I think it has more flexible design, it was way easier to test and achieve good enough test coverage. I'm currently at a stage when I need some subtle tips to move on further refinements (or.. fixes).

Please find project implementation at my GitHub area. For those who don't know the mentioned project, please read the description on Wikipedia.

Thanks.

Software craftsmanship events worth knowing, attending...

(sorted by the 'when' in an ascending order)

Name	When	Where	About
Hackathon	~Mid of October (lasts 1-2 day(s))	Physical attendance. Facilitated all around the world.	A design sprint-like event in which computer programmers and others involved in software development, including graphic designers, interface designers, project managers, and others, often including subject-matter-experts, collaborate intensively on software projects.
Global Day of Coderetreat	~Mid of November (lasts 1 day)	Physical attendance. Facilitated all around the world.	Intensive practice event, focusing on the fundamentals of software development and design.
Advent of Code	~1st Dec - ~25th Dec (25 days long)	Online attendance.	Fun series of small programming puzzles for a variety of skill levels.

And modulus really help you to extract digits.

Think how dividing and using modulus operator you can extract individual digits. Brute force way to understand is to get calculator and play a bit (with some pretty predictable numbers to use for division, modulus) and see what you get.