Per Lundholm

Continue reading: How to hire a real star developer

How to hire a real star developer

What makes the difference between a star developer and a day coder? First of all, with a star developer I don’t mean star as in ”famous”, rather as in ”elite”.  And, a day coder is OK to be, no disrespect here. We need you as much as we need the elite.

My point here is that if you wish to hire a real star, you need to know what to look for.

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Continue reading: Window, Scene and Node coordinates in JavaFX

Window, Scene and Node coordinates in JavaFX

Here is an illustration on how the coordinate systems of the screen and JavaFX objects relate to each other. It is a great thing with JavaFX that you seldom bother about screen coordinates. Instead you rely on layout managers to position your nodes on screen. A node has its own coordinate system, should you like to do some positioning, e.g. in a game.
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Continue reading: An Analog Clock in JavaFX

An Analog Clock in JavaFX

JavaFX is great fun but there are so many ways of doing things. You can use FXML, you can use images to build things piecewise or you can write code for a live, scalable design.  The latter is the case here where I show how I created an analog clock using Java code.

Analog Clock with desktop in background
The clock is designed with the clockwork in a separate class and the face in another.

This text shows some example JavaFX code in Java slightly above introductory level. You should have your development set up and done at least a first program.

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Continue reading: Clamp The Code

Clamp The Code

This a picture of me used on our front web page. If you don’t see it there, try reloading.

What’s the matter with me on the picture?  What am I trying to say?

Per Code Clamping
Per Code Clamping

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Continue reading: Lessons on the looks of UI

Lessons on the looks of UI

My mother’s sister is past 80 and still running her own company. Naturally, I do her IT-support since -95 when she realised that it was important to utilise a computer for her business.
The other day I was installing an invoice program for her. She has been using an Excel template, designed by my wife. But new regulations on VAT made her go for specialised software. She choose a well established product. It turned into a lesson for me.
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Continue reading: On Unit Testing and Mockito

On Unit Testing and Mockito

This is just a blog post to point to my presentation of the aforementioned subject. Or should I say, “prezi”, because there are no slides, just a big picture with a path through it. That’s is the way of Prezi presentations and as a first timer, I felt liberated. Slides are so dull!

The content of my presentation is aimed at those with some experience of unit testing that would like a dose of philosophy on testing styles. Classical or Mockist? State or Behavior? Also, if you are not that familiar with Mockito, take this prezi for a spin!

Here is the link to the prezi! That’s all for now.

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Continue reading: Product Owner’s Product and Project Board

Product Owner’s Product and Project Board

The team has its Scrum board as an information radiator. It is an excellent way of getting an overview of the sprint. But what about us, the product owners, don’t we need that too? Of course we do, we too have a need for an overview of our work and to radiate information. The stakeholders pass by and ask “what’s in next sprint”, “when will we migrate”. We’d like to just answer with a light gesture towards the wall. It is all there for everyone to see.

Let me tell you how our project owner board works, as an example.Continue reading

Continue reading: Shared Values Build Teams

Shared Values Build Teams

What makes a group of good people a great team? I believe that shared values and experiences are fundamental. While there are many team-building activities available, such as paint ball and boule, I’d like to think that software development teams need more than that.

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Continue reading: The TDD Tetrahedron, version 2.0

The TDD Tetrahedron, version 2.0

The TDD Tetrahedron, or if you wish, pyramid, has reached 2.0. Like cars, the new model is bigger and comes with new technology.

By pure coincidence, I ran into somebody willing to print this. So here it is, the version 2.0 of the TDD Tetrahedron. The new version has sides of 100 mm and it is made of plastic.

What’s it for?

Well, if you didn’t use the older version, you may be wondering what’s so great about this. It is all about mental focus.

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Continue reading: Becoming a Product Owner, Part 2

Becoming a Product Owner, Part 2

Here is part 2, a week has past. I think as I write so it is a bit different in style and content than my other posts here.

It has been a hectic week, this first week as PO/SM. First of all, it was only four days thanks to national day. Then there were two new developers from Russia which meant twice as many developers as we had before, not counting me. Simple, you just tell people to pair program. That works out if they are well enough to come to work. Which they weren’t. So they russians were left a bit hanging. I had a lot to do just to keep the team running, at least according to my standards.

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Continue reading: Becoming a Product Owner, Part 1

Becoming a Product Owner, Part 1

I am programmer and Scrum Master but has been offered to become Product Owner for the same part of the product I am currently working on. I decided to accept the offer and this is my live story, written as I go. Perhaps this will be of interest to you.

First of all, to me, this was not a decision I took lighthearted. However, I do have the fortune of peer coaching at Crisp and the offer came the same morning we had our last coaching. That was a timing like there was a meaning behind.

It is not supposed to be full-time either, so I need to choose what I shall do the rest of my day. It turned out that initially there was no choice. It was not possibly to find a Scrum Master to fill in my gap. The next sprint I will be both PO and SM. Hua!Continue reading

Continue reading: Tools of Our Trade

Tools of Our Trade

Today we developers are high in demand, at least here in Sweden. My client is now persuading russians to immigrate only because there are not enough of skilled programmers. While there still are people that think one programmer is as good as another, give or take some experience, others have realized that there is a huge difference.Continue reading

Continue reading: State of My Agile Mind

State of My Agile Mind

It has been 10 years since the Agile Manifesto was written and although I have not been following the agile community for that long, I have been a developer in Scrum teams since 2007. In total, I have done system development for 30+ years so I have lived and breathed both waterfall and RUP before trying Scrum.

So what is on an agile developer’s mind these days? Here are my current reflections on three things today, Agile Development, Architecture and Acceptance Testing.

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Continue reading: The TDD Pen

The TDD Pen

Hi there.

Just wanted to show you our latest widget: The TDD Pen.

You may think that it is an ordinary pen but it is not. When you hold this pen you immediately become a superb programmer. Not only will you write tests that cover all your code, you will also write bug-free code and refactor everything into stunning beauty!

You only have to figure out how to hold a pen in one hand and still type the keyboard without being embarrassingly slow. 🙂

Picture of TDD Pen

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Continue reading: Write Legacy Code and Secure Your Job

Write Legacy Code and Secure Your Job

In this day and age with unstable economics, constant change in how to work with software, new languages and databases popping up from nowhere, it is important to cement yourself into your position at work.

Follow this guide and be sure of never being fired, no matter what.Continue reading

Continue reading: Canned Wicket Test Examples

Canned Wicket Test Examples

Unit testing of the GUI is not the same as unit testing through the GUI. We are interested in the logic of the GUI rather than the placement and order of the GUI widgets on screen.

Testing the logic makes the tests less sensitive to changes in presentation but introduces the problem of JavaScript dependent features. AJAX is in the vogue so we wish to be able to do testing of that too without being forced to start a browser. There is some support for AJAX in Wicket that may be reached using the test framework that is part of Wicket. However, it is not straightforward to use and there are some pitfalls.

Here are three examples of avoiding those, one for each of the check box, drop down and radio group controls.Continue reading

Continue reading: Some Gotchas for Java Developers Learning JavaFX

Some Gotchas for Java Developers Learning JavaFX

In an earlier post, I had attached slides from a presentation on JavaFX that contained some code examples. I discovered that at least one of them, the ball game, stopped working when I switched to JavaFX 1.3.

I would say it is a quite subtle difference.

What happened was that the onKeyPressed and onKeyReleased were not called. My immediate reaction was that it was due to some bug in JavaFX but yesterday I realized what had happened.

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Continue reading: Agile and Architecture

Agile and Architecture

Yesterday I held a presentation on the subject "Agile and Architecture" at EDB. They have an internal competence network which meet

regularly and discuss agile processes and methods.

My point in this presentation was that every system has an architecture that determines the qualities of it. Given a set of functions, different architectures will give these functions different qualities, such as performance and cost of maintenance.

This is still true, no matter if you do waterfall, RUP or Scrum.

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Continue reading: Lean vs Traditional Project Management

Lean vs Traditional Project Management

This week, we have Mary Poppendieck with us. She held an evening seminar which inspired me to think about the differences between Lean and traditional project management. I also am inspired by the questions I get from my spouse on this.

I thought that it would be interesting to do a side-by-side comparison between the two. I am no process expert, I am just a programmer who has been the subject of 30 years of different processes. I have seen DOD 2167, RUP, PROPS, PEJL, XP, Scrum and a few others. So this is just my humble opinion.

See also what Henrik Kniberg wrote earlier in his blog.Continue reading

Continue reading: Jada jada JavaFX – Why I Love the Idea

Jada jada JavaFX – Why I Love the Idea

The other day I held a three-hour workshop, an introduction to JavaFX for some colleagues. The great thing about doing it, is that it forced me to answer the question: why is it necessary to create a new language just for GUI?

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Continue reading: The TDD Tetrahedron, version 1.0

The TDD Tetrahedron, version 1.0

The TDD Tetrahedron has reached version 1.0.

As I write this, we have a course on advanced TDD with Robert C Martin as teacher.  I took the opportunity to introduce the first version to the participants.
 Uncle Bob and the TDD Tetrahedron
Uncle Bob and the TDD Tetrahedron.

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Continue reading: TDD Illustrated

TDD Illustrated

I am planning an introductory course on TDD. In that process I have been thinking about how to convey the productivity gain with TDD.

Being a visual person, I had an idea that would illustrate this in a few pictures. Here they are for your scrutiny and enjoyment!

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Continue reading: The TDD Tetrahedron

The TDD Tetrahedron

Are you looking for some concrete expression for Test Driven Development? Let me give you a glimpse of what I am working currently on – the TDD Tetrahedron.

The idea originates from when a colleague at Crisp, David Barnholdt, wrote about not focusing on one step at the time. So I thought for a while and came up with this idea, a tetrahedron where each side displayed “failing test”, “implementation” and “refactor”, respectively.

tdd tetrahedron

You turn it and look at the first side where you read “failing test”. You write a failing test and turn it again, reading “implementation”. Write the implementation and run the test to get the green bar. Once again you turn the tetrahedron and read “refactor”. You look for something to refactor, confident that if you do, you will be supported by unit tests all the way.

Or the thing just sit on your table to tell everyone how cool you are as being a TDD programmer. At least wish to be. 🙂

Anyways, here are some sneak preview pictures of the greatest thing that ever happened to the world of programming, ta da – the TDD Tetrahedron!

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Continue reading: Change Based Configuration Management

Change Based Configuration Management

Configuration Management (CM) is crucial to any software project as neglecting it will easily get you in big trouble. It may look like bad luck, but it is not.

A CM-plan will deal with several matters, from simple to decide things, such as naming of releases to more advanced subjects, such as branching strategy. I will talk about the latter today.

There are of course different ideas about what a good branching strategy should be. It is my firm belief that it must be aligned with the subject at hand, namely changes.

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Continue reading: Beyond Basic TDD

Beyond Basic TDD

This coming spring we will host a course with Robert C Martin on advanced TDD. I would really appreciate the input from my experienced TDD readers on what they consider to be the largest obstacles when it comes to TDD. This is your chance to shape the event so that it is customized to meet your needs.

A few months ago we hosted a very popular course with Michael Feathers. He talked about refactoring legacy systems and of course, unit tests which are an essential part of that. But the crowd cried out for more.

I have been practicing TDD for two years. I program in Java and frequently use Mockito and Wicket. The latter has support for unit testing web interfaces and it is great although it has its quirks.

But what is everyone else doing?

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Continue reading: Not the Fixed Price Contract

Not the Fixed Price Contract

The fixed price contract has been discussed here at the Crisp blog by others. It is broken by design as it creates more problem than it fixes.

On the way from JAOO I talked to Udi Dahan and that made it fall into place in a different fashion. Not that this is what he said, this is what he sparked.

The fixed price contract is not necessarily fixed price, a contract or evil.

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Continue reading: Design Principles for Error Handling

Design Principles for Error Handling

Besides understanding the most important structures of a system, it is an architect’s responsibility to understand and influence the design principles.

One common and important set of principles are those of error handling. It is good to have the same principles throughout the system as it produces fewer surprises and mistakes.

In this post, I will discuss some principles that including checked exceptions and Null Object, which you may not fancy. But it is always good to think this subject through, so please come along.

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Continue reading: The Last on Code Review

The Last on Code Review

Code quality. It has been haunting me for so long I forgot when I started to think about it. Do other people think about it? For sure. Do everyone? Certainly not.

I was doing RUP and before that some waterfall process from DoD. Before that I was programming Fortran. Now, what has been my single most important recommendation for reaching code quality?

Peer code review.

But enough. It just struck me how much I do not miss code reviews.

I’ll tell you why and I’ll tell you what is the replacement, because there should be one.

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Continue reading: Modal Windows Considered Harmful

Modal Windows Considered Harmful

On the Wicket user’s mailing list there was a question about modal windows and it set me off. Since my excellent wisdom 😉 is larger than just modal windows and Wicket, I thought that it would be of interest to all of you, dear readers.

I have discovered that the modal windows that was gone when web applications started to spread, are starting to come back. And they are bad, even if they are not as bad as the goto statement that was accused the same way as I just did: harmful.

A modal window is something that pops up in the face of the user, screaming its importance by not letting the user touch anything else until the modal window had its way.

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Continue reading: Stable Interfaces – any good?

Stable Interfaces – any good?

I once worked in a rather large project, about 1000 persons. There are many stories about that project but the one that I’m thinking of now is that we loved to say "stable interface, we must have stable interfaces".

Now, stable means not changing which means nothing gets better. So why would anyone want stable interfaces? And what should we say about the opposite, "unstable"?

Stable interfaces is a cornerstone in tactics for modifiability, so how do stability and modifiability go hand in hand?

Do you see my finger?

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