Moving away from SlideShare

One of my learning activities is watching recordings of conference presentations, especially ones which have been recommended by trusted colleagues and peers. (You can find presentations which I recommend myself on YouTube and Vimeo.) After watching I usually download the slides and store them in my knowledge base, together with notes I might have taken during the presentation. At the moment my software development knowledge base is around 6G text files and PDFs, but that is a topic for another time.

From time to time I present at conferences or run a Coding Dojo. Afterwards I want to share my slides and I want you to be able to download them. In 2013 I started using SlideShare for that. I liked it and it worked well. It organised my slides and added the social aspect on top, e.g. I connected with other people sharing slides and kept track of favourites. Since Scribd acquired SlideShare I am not satisfied any more. I am facing technical problems uploading new slides again and again which is frustrating. Additionally downloading slides seems to require a paid membership. While I understand that free services need money to operate, I really want my slides to be available for download.

So I am moving away from SlideShare, or at least I am duplicating it. I did not follow my own advice to avoid third party SaaS - and as in the past I have to deal with the consequences now. I uploaded all slides I had shared on SlideShare to my own folder on my web space. It is just a folder and not as fancy as SlideShare, but you can download! Enjoy my slides.

CodeCopTour Week 7

I think it would speed things up if I cover two weeks of my Pair Programming Tour in one swoop, as I did two weeks ago. I want to share some insights besides the usual diary, so I need to increase my writing throughput. On the other hand I do not like going faster because writing a blog post takes as long as it takes. Although I know people who do speed blogging, the OCD part of my personality does not like short-cuts, obviously.

Last week I was hosted by Thomas Baldauf of the Austrian Environment Agency. I did not know Thomas but had got his name from a friend. After a short email he immediately agreed to host me without any questions which surprised me a lot. Unfortunately Thomas, the lead of the development team, did not have time to work with me in person but had prepared some developers from his team for my visit. I worked with Nexhat Gashi on a small feature of their newest web application which is based on JSF technology. I did not know JSF before I started my tour, but saw it all the time when pairing with people. Probably I will be fluent with JSF until end of November ;-)

I also worked with Martin Lackner whom I knew as long time attendee of our Eclipse DemoCamps in Vienna. Martin, an Eclipse platform veteran, worked on an MDA prototype using Xtext. I had worked with the older versions 0.7 and 1.0 before and he had prepared all the nitty-gritty details in the previous week. I reviewed his DSL and probably spoilt all his fun by proposing a different, shorter syntax. We moved forward very fast. In only one day we created a technical language to define entities and aggregates, together with full editor support, code completion, validation and proper formatting. Such is the power of Xtext - I love it. If you do not know Xtext, I really encourage you to check it out. The Eclipse Xtext project has excellent documentation and many examples which provide a starting point to get your DSL up and running in no time.

Free Lunch
The only compensation I asked for pairing was food and beverages throughout the day. It worked out well - till now I have been provided with free lunch every day. All my hosts were very polite and offered me coffee or drinks and asked me for my preferences when choosing places to eat. I never asked for anything special but went for lunch where my partners went. I visited take-away noodle stores, staff canteens and fancy restaurants. Having lunch with many people, together with the various places in Vienna I have been to, was a culinary trip of its own.

The two weeks I spent away from home, I stayed in a hotel. The host company refunded me 600 Euro for my expenses per week. It was a nice hotel, expensive but comfortable. The money was sufficient because I saved on food, eating in the company canteen now and then. Staying in a hotel and working all day was acceptable for the two weeks, and I enjoyed the rich breakfast buffet including bacon and scrambled eggs. But I would not like to stay in a hotel for extended periods of time. I am not a travelling person and I never worked like that. I enjoy going home after work, where connectivity is good and wireless network is free ;-)

Can PL/SQL be Clean?
At the end of the week I spoke at the Austrian Oracle User Group. The organizer had planned an event focusing on clean development and three friends had recommended me to him independently. I agreed to give a presentation but was not sure about the topic I should talk about. For talking to an Oracle user group, the first thing that came to my mind was PL/SQL, Oracle's database language. I have seen horrible pieces of PL/SQL and the question was if it can be written in a clean way? According to Michael Feathers, the author of Working Effectively with Legacy Code, "clean code looks like it was written by someone who cares." I presented his quote as first rule of clean code. Continuing the discussion I listed several books about clean code, including Code Complete by Steve McConnell. Steve said to "write programs for people first, computers second", which I defined as second rule of clean code. Following both rules it was obvious that even PL/SQL can be written in a clean way. I got good feedback on my presentation, especially that it was very entertaining, so I encourage you to check out the slides on Slideshare.

CodeCopTour Week 3

I was waiting for the legal advisor of TechTalk to review the five lines I wrote about my visit at their office the week before, which caused some delay in my blogging queue, but now I am back on track and will continue with week number three of my tour. I started the week with going to the country-side of Lower Austria. While driving I reflected about my tour (and I already published my thoughts here). Markus Schinerl had invited me to stay at his house for three days. Markus runs a small company called sdguide.org which is specialized in calculating metrics like the carbon footprint for factories in the pulp and paper industry. Pulp and paper is a very competitive industry and customers like governments demand the highest environment-conserving certificates from their paper providers. Sdguide's office was located in an old house and due to old age and structural damage it was under construction and looked terrible, see the image on the right side. Some windows were broken and we worked on a raw, wooden construction resembling a table. However we had a powerful computer, two keyboards and two huge screens - no problem there ;-)

Spreadsheet Monstrosities
Markus used a gigantic spreadsheet to enter all parameters needed for such a calculation. It contained roughly 200 input parameters and 500 metrics for up to 50 product parts resulting in huge files with thousand of lines. Obviously Excel was reaching its limits and he needed something more powerful. We spent the first day discussing the domain of carbon footprint and created a small diagram defining the core elements of his calculations. Although we did not write any code it was a productive day because I helped Markus to reflect on his needs and he explained the requirement to me at the same time. We came to the shared conclusion that he needed a real database, but one that he might be able to develop himself, so we ended with Visual Basic (for Applications aka VBA) and MS Access. Although I did not fancy VBA it was the best choice for his needs and he liked the idea that he would be able to use parts of our VBA code in his spreadsheets as well.

Markus had used VBA some years ago and I had never worked with it before. It took us half of a day googling and reading StackOverflow until we got fluent and then we flew. VBA does not offer much and I missed a lot like unit testing, collection classes, closures and much more, still we made good progress. At the end of the second day, actually the very end of the day - it was 10pm, we had built full end-to-end functionality. Of course it was not finished and only calculated one simple formula of one metric for one product part without considering scenarios, different years or different customers. Still it showed the way. I had aimed for that because we needed to know if the chosen design would work. It looked good. During the third day we added more features Markus wanted to investigate, we even created an infix math parser to evaluate arbitrary formulas. It was great and I learned a lot.

Being Brutal
Back in Vienna I helped a small team of developers to improve their refactoring skills. The developers liked practice and I chose Adrian Bolboaca's Brutal Refactoring Game. I had participated in Adrian's session during XP2013 earlier this year and had liked it a lot. It is a programming challenge focusing on refactoring. The brutal part is that each code smell needs to be refactored right now, regardless how small it is. This makes an excellent exercise to train developers in spotting code smells and refactoring them. Adrian lists 17 code smells as the base of the game and I asked the team to prepare short presentations about each of them. At the beginning of the session the developers presented the material to the audience. I just love when trainees teach themselves ;-) During the sessions I collected all the smells I had flagged. Half of them was about naming, i.e. "name not from domain" and "name not revealing intent" which did not surprise me because naming is a difficult problem. Further 30% were "Primitive Obsession" and "lack of tests", common problems in most code bases. One participant was disappointed that he did not hit each of the 17 smells at some point during the game - maybe I will add some game like achievements for completionists like him.

Even for a small group it was demanding to watch out for the smallest code smell in several evolving code bases at the same time. I noticed that pairs kept hitting the same smells again and again. Besides naming, which all participants had to deal with, one pair was "obsessed with primitives" several times, whereas another team had trouble writing tests to cover their design ideas. A fast typing pair, two developers who knew their IDEs well, created a lot of code, but as soon as I found a smell they were unable to remove it by refactoring and had to delete the new code and start over. Although I was as brutal as possible and challenged the participants a lot, I got positive feedback after the exercise and all participants learned something.

The Java User Groups of Austria
For the rest of the week I went "on tour" with the Java Klassentreffen 2013. The Klassentreffen is a series of events organized by the Austrian Java training company Ciit and sponsored by Oracle. It is a mixture of sales pitches and technical presentations, covering various aspects of Java. Technically the Klassentreffen did not meet my requirements for the pair programming tour, but the organizers had invited me to speak and food was provided. Together with Martin Ahrer, the founder of the eJUG Austria, I introduced the audience to Java and Java related user groups in Austria. I started my talk with the reasons to attend user groups, then covered the core groups of Java, Eclipse, Android and Scala and finished the presentation with Open Source, Software Craftsmanship and upcoming Code Retreats. (For details and links please open the slides.) Later the leaders of several groups told me about new registrations, so I guess my presentation was a full success.

CodeCopTour Week 1

Finally my Journeyman tour started last week. My first host was Raphael Stary from letsplay.io, a fresh startup creating the next level of social games. The "next level of social games" sounded like a mixture of FarmVille and World of Warcraft ;-) - playing with your friends using your mobile phone - hot stuff! Raphael was very kind and it was a great experience. After some initial chitchat he revealed his plans for me: to use my Java skills for creating the server side component of his newest game. We spent three days pairing intensively and I was happy with our result, an almost complete back-end including integration tests. All the discussions about the domain and the technical details of browser based games sparked the idea to create my own game. I used to code little games many years ago and had forgotten the joy of doing so. Maybe I will create something small after my tour when things have settled down again.
Being in Sektor5, a relaxed local coworking space, I took the opportunity to visit another startup, Blossom, a lean Kanban board. Blossom was founded a few years ago, and after winning some funding they mainly operate in the San Francisco area now. Blossom has customers from companies like Twitter or Google, an impressive feat for a Viennese startup. Blossom CTO Nik Graf paired with me for two days. He showed me their impressive technology stack and I saw many technologies I had never seen before, probably too much to digest in two days. I enjoyed the atmosphere of a real technology startup. Rock on guys! (I confess I am a Blossom fan boy now, just like half of the coworking space ;-)

During my tour I plan to visit as many user group meetings as possible. The Vienna Ruby Group meets in the same coworking space and I squeezed myself into the agenda and introduced the Ruby enthusiasts of Vienna to the idea of Software Craftsmanship and the Journeyman Tour. After the presentations we had a great discussion about craftsmanship, pair programming, and quality in general. I liked talking to passionate developers and will attend future meetings as well.

Last week was a blast. I learned a lot both about our craft and myself. My journal is full with notes and findings, which I will share in shorter posts in the next days.

Moved to Slideshare

After watching a presentation about SlideShare by Luis Suarez, the "E-mail-less Man", I decided to give it a try. I brushed up some of my past presentations and uploaded them to SlideShare. New slides will be added occasionally, so stay in touch. Thank you Luis for motivating me ;-)

My Favourite Topic

Last month I had the opportunity to take part in a job assessment of the Austrian Software Test Experts. The managing directors and I have been friends since long as would be expected from guys who say that "software test is cool" and a "fanatic about code quality". I was looking forward to meeting the whole staff of testing experts.

The CEO had asked me to prepare an introduction and a short presentation about some code quality related topic. Unfortunately I had a very busy time and wasn't able to prepare anything in-depth. The night before I just hacked together a little presentation by copying all kind of slides from some of my previous presentations. Stealing the joke from Uncle Bob's talk Craftsmanship and Policy (2:30), I titled it My Favourite Topic, which is of course - me. ;-)

Feedback
I didn't take the presentation too seriously however the CEO said it was hilarious, almost comedy styled. People who had known me liked it a lot. But it turned out that I did a really poor job. Half of the audience didn't get the joke and therefore did not know what I was talking about. They got the humorous, self-deprecating introduction wrong and were discussing if I was disrespectful or just unprofessional. They hauled me over the coals.

Code Quality Assurance v2

Last week I gave my presentation on code quality assurance, for the second time this year, and it looks like it will become an integral part of the lecture. That would be great. Maybe one or another soon-to-be developer will get interested by the ways of the craftsmanship and not become a Duct Tape programmer.

I was quite nervous in the beginning of the presentation as I had never spoken in front of so few people :-) Honestly, giving it the second time helped me a lot and I was much more relaxed and didn't hide behind my laptop most of the time. There were few students, but they asked clever questions in the end. Only one student complained about too much mathematics needed to solve the prime factors kata. Well it's not that complicated, but maybe I will try the word wrap kata next time.

Dear Students
There is a list of references at the end of the slides, only a few but you should read them. Go ahead, read them now! I will wait here. If you are desperate you might listen to the recording of last year's quality assurance presentation. It's missing the demos, but my explanations should give you a general idea of what's going on. Good luck and don't succumb to the dark side!

Concepts of Functional Programming

Last week I had the pleasure to give a presentation at Javaabend in Vienna. Javaabend (German for Java evening) is a local Java user group event organised by openForce Information Technology at irregular intervals.

A Little Rant
This presentation has a long history, so I will start with a little rant. Last year when I started playing around with Scala, we (read some enthusiastic employees) formed an informal study group to have a look at functional languages and Scala in particular. In the beginning we made good progress and had quite some fun and met biweekly. Unfortunately the organisation had a strange attitude to training (as well as to public relations) and we were disbanded. Being stubborn as I am, I managed to establish a budget from "another source" after some time and started preparing this presentation for the monthly "Developer Round Table". The presentation was postponed several times and in the end I left the company for good.

Scope of Presentation
Now let's come back to the presentation. Talking about the principles of functional programming is a bit off-topic for the Code Cop and it's just scratching the surface of the core principles: purity, higher order functions, closures, currying, continuations and (well not really) monads. I'm no expert on functional programming, so feel free to comment corrections or clarifications. Especially the concept of monads is a bit mysterious.

Slides
Download the Concepts of Functional Programming slides. As usual the slides are not very useful without my explanations because they entirely consist of single words and/or images. This is my take on the current presentation style. I received some good feedback on the style and especially the images. One attendee even told me that the images were "too" good for him, he was distracted by them. (Thank you Flickr community for all these wonderful CC licensed images.)

Discussion
After the presentation there was an interesting discussion on the advantages of functional programming over the imperative style, e.g. Java.

• Is it easier to get things done with many lines of simple, imperative code, compared to one line of functional code (that most definitely does not look simple when you are new to the area)?
• Are the functional paradigms more difficult to comprehend? Is this the reason that functional programming isn't used as widespread as the imperative one? Would the average developer produce bad quality code when using functional languages?

These are difficult questions, only time will tell.

Resources

• Slava Akhmechet explains functional programming for the rest of us. This is a nice overview and definitely worth reading.
• Tony Morris posted slides of his talk what functional programming means.
• Some code examples were taken from Ruby Blocks, Closures, and Continuations.
• A good resource for all concepts is Wikipedia.

Acknowledgement
Researching the core principles of functional programming was part of a System One Research Day.

Code Quality Assurance

Last week I had the opportunity to give an one hour presentation on code quality assurance as part of the lecture on software testing to students of the Fachhochschule Technikum Wien. By "code quality assurance" I meant principles and techniques used by software developers to test their software and keep it free of bugs.

I believe that the most important ingredient of code quality is the mind-set of the developer. So I started with some slides about the Zero-Defect Mindset and Software Craftsmanship. Then I did a live demo performing the Prime Factors Code Kata to show the basics of unit testing, Test-Driven Development and regression testing. This was the main part of the presentation.

After that I explained the principles of code coverage, continuous integration, static code analysis and code reviews to the students. I mixed the theory (slides) with hands-on examples on the newly created Java code using EclEmma, Hudson, PMD and ReviewClipse.

Doing the demo was fun and the whole presentation was a success. For the demo I tried to stick to Scott Hanselman's Tips for a Successful Technical Presentation, esp. font size (Lucida Console, 16pt). Here is my "BigFonty" checklist:

• Create a new, clean user profile for presentation only.
• Set icons to large and number of colours to maximum.
• Remove all icons from the desktop and choose a plain desktop background. I like to minimise all windows if I get lost between them.
• Disable any screen saver and turn off energy saving. Otherwise they will definitely activate at the most annoying moment.
• Set the command shell font to Lucida Console 16 point, bold, green on black. Have the default shell point to your main demo directory.
• Clean up the browser, remove unnecessary tool bars and symbols. Unfortunately, at least in Windows, new users always have tons of crap on the desktop and in the browser.
• Set the default browser page to empty or your main demo web-site.
• Set the font size in your browser to very large and enable override of font sizes in styles. This is done in some accessibility sub-menu.
• Use the browser in full screen mode (F11). You need all the space available for the large text.
• Set the main font in your IDE to Lucida Console 16. In Eclipse it's enough to change the Text Font (in the Basic category in the sub-menu Colours and Fonts in Appearance).
• Turn on line numbering in the IDE for quick reference of single lines.
• Maximise the IDE and use a full screen source window whenever possible. In Eclipse just press Ctrl-M to maximise a view.
• Start all applications like IDE or any server before the presentation. They may take some time.

(Download slides or source of Prime Factors Code Kata.)

Update 20 April 2010

Student Feedback

Today I got the feedback evaluation from FH Technikum Wien. Several students mentioned my presentation as exciting and full of practical experience. :-) One called my presentation idiosyncratic - I don't mind, it definitely was. It's only weak point was that students were not able to study using the slides alone. Next time I will prepare some handouts with more information.

Update 8 May 2010

German Podcast of Presentation

I finally managed to post-process the (German) audio stream of the talk and combine it with the slides. Watch the quality assurance podcast (in German). It's still missing the demos, but my explanations should give you a general idea what's going on.

First Eclipse DemoCamp Vienna

It all started when my buddy and Eclipse Xtext committer Michael Clay told me about the Eclipse DemoCamp idea with so much enthusiasm that I agreed to help him organising the first Eclipse DemoCamp in Vienna.

We lined up with the local Java Student User Group and started inviting speakers. To our surprise there was absolutely no problem to find speakers and even sponsors. 200 emails later we ended up with 10 presentations and 8 sponsors (beside the Eclipse Foundation which sponsors all demo camps).

When Jeff and Chris of EclipseSource offered a presentation, we were delighted but had to drop our own talks about Free Quality and Code Metric Plugins and Xtext NG to provide some space for these well known Eclipse veterans. (So, as usually there was no time for code quality topics ;-) Interest of people to attend as well as give a speech was quite high. I'm sure we could have added a second track but did not want to because of Bjorn Freeman-Benson's recommendation for Eclipse X Days.

JSUG had organised the room and infrastructure for us. The enthusiasts of the core team helped the speakers prepare their stuff while I was giving them our Eclipse DemoCamp shirts. When the presentation started there were more than 80 people in the room. I had the pleasure to welcome them and present the agenda. Although I only had ten slides I was very nervous. It was the first time I spoke in front of that many people.

Werner Keil started with an introduction of the Spatio-Temporal Epidemiological Modeler (STEM). He talked about its general application and importance. In the end he played an interesting video showing simulated infection rates throughout the world.

Next the Lixto development team presented some features of their RCP based screen scraper and how they used JFace components to render the different GUIs of the Lixto Visual Developer application.

The Eclipse plugin ReviewClipse was presented by Christoph Mayerhofer. It's a useful tool to make code reviews easier and thus more likely to be done. Obviously a code cop has to love it. Currently I'm reading all diffs from junior developers every morning. So I'll give it a try.

Chris Aniszczyk and Jeff McAffer are both seasoned speakers and furthermore good entertainers. In a whirlwind tour of the Toast demo application they showed what you can do with EclipseRT technologies. Believe me, it's cool stuff.

The last presentation of the first block was about e4, the future platform of Eclipse, given by well known Eclipse committer Tom Schindl. Tom is probably one of the most motivated Eclipse enthusiasts. You can feel the fire burning in him when he's talking about his work, very stimulating. And he hates singletons as much as I do. Good boy.

Half an hour planned break was way too short to eat 400 sandwiches together with water, Red Bull and smoothies. Michael even went to fetch some beer because Chris had written that he is looking forward to Austria and the Austrian Stiegl Bier. People were enjoying the sandwiches, standing together in small groups and chatting away. Unfortunately I didn't have time to talk to everybody I knew.

Our "modelling track" was opened by Robert Handschmann's demo of the Serapis language workbench. It looked mature and makes model driven development quite easy. I liked most that Robert was able to answer all questions regarding additional features by simply showing the feature in the workbench.

After that Maximilian Weißböck explained the basics of Model Driven Software Development and showed how easy it's to add stuff when you have a working modelling solution. He finished with the advice to always use a modelling approach because the tools (read Xtext) are mature enough to pay off even for small projects.

Next Karl Hönninger gave a short demo of openXMA, a RIA technology based on EMF and SWT. Now XMA is not your 'new and sexy' technology, but it's 'improving'. The new openXMA DSL is based on Xtext and combines domain and presentation layer modelling. Karl used a series of one minute screencasts to demo the XMA Eclipse tool chain. That's a good idea to make sure that the demos work and still to be flexible enough to skip parts of the demo.

Then Florian Pirchner showed how they had created dynamic RCP Views enriched with Riena Ridgets that interpret their EMF model and update in real-time: Riena-EMF-Dynamic-Views. Redview seemed like magic to me (either that or I was already getting tired ;-).

Unfortunately I was not able to attend the last presentation given by Philip Langer about model refactoring by example. Michael and I were busy preparing to move on to the chosen "beer place". In the end approx. 30 people made it there. In the nice atmosphere of our own room we had some beer and vivid discussions. For example I have some (blurred) memories of Michael showing slides of some Xtext presentation on his notebook. The evening ended when the waiter threw us out half an hour past closing time (midnight).

Organising a demo camp is work. But it's also fun. And obviously it paid off. It was great. Thank you everybody for making it such a nice evening. Maybe we'll see each other again next year.

Practical Unit Testing

In the beginning of June I gave a presentation about practical unit testing with JUnit at the Java Student User Group in Vienna. JSUG is a small group of dedicated students that formed last year. The scope was practical as well as pragmatic - in fact just bits of information I considered useful for the daily development. It was good to see young developers that are eager to write tests. I hope when they are thrown into legacy code later in their career that their principles will not just crumble.

Download the Practical Unit Testing presentation slides.

Resources used in the slides:
This section contains links to topics I talked about. I give a list of all my sources. Hopefully Google does not punish me for creating this link-farm like page ;-)

JUnit basics used sources from Unit testing (Wikipedia), JUnit.org & JUnit, Early look at JUnit 4, Design to Unit Test, Test-driven design, Part 1 & Part 2; Checkstyle, FindBugs and PMD.

The mocking chapter used sources from jMock, EasyMock (Easier testing with EasyMock), Initializing bean using EasyMock, Mocking & Spring, Oh no, we're testing the Mock! and the Law Of Demeter.

Singletons are a pain for testing: Patterns I Hate, Singletons Are Evil and Why Singletons are Evil, Refactor singleton, Test flexibly with AspectJ and mock objects with AspectJ and the Google Singleton Detector.

There are some tools to help testing J2EE apps: HtmlUnit/HttpUnit, HttpClient, Testing Servlets and ServletUnit, Jetty, Cactus, Simple-JNDI, MockEJB and ActiveMQ.

Tuning the tests means often tuning the database: DbUnit, H2 and HSQLDB.

The Code Coverage chapter talks about EMMA (EclEmma), Cobertura, Agitar but Don't be fooled by the coverage report, Crap4j, Testability Explorer.

A new trend is testing with scripts: Unit test your Java code faster with Groovy or Using JRuby for Java testing, RSpec, JRuby, JtestR and ScalaCheck/Specs.

Finally some cool tools for testing and the build are JUnitPerf, SWTBot, XmlUnit, Distributed JUnit and GridGain.