What is MapStruct?According to MapStruct website:MapStruct is a code generator that greatly simplifies the implementation of mappings between Java bean types based on a convention over configuration approach. The generated mapping code uses plain metho…
MapStruct is a code generator that greatly simplifies the implementation of mappings between Java bean types based on a convention over configuration approach. The generated mapping code uses plain method invocations and thus is fast, type-safe and easy to understand.
Inject MapStruct mapper in Blueprint OSGi
Such mappings are sometimes necessary in our integration projects. We also use OSGi to create our applications and Blueprint for dependency injection. Blueprin Maven Plugin makes it very easy to use, providing annotation support.
MapStruct supports component models like cdi, spring and jsr330, so generated classes could be used as beans. Fortunately, Blueprint Maven Plugin uses annotations from JSR 330, such as Singleton or Named.
The only thing we have to do is to add property componentModel with value jsr330 to a mapping interface:
@Mapper(componentModel = "jsr330")
public interface PersonMapper {
Person toDomain(PersonDto personDto);
}
and now we can inject PersonMapper to our beans:
@Singleton
@AllArgsConstructor
public class CreatePersonHandler {
private final PersonRepository personRepository;
private final PersonMapper personMapper;
// ...
}
Blueprint Maven Plugin will generate an XML file with bean PersonMapperImpl and inject it to CreatePersonHandler:
Generate all mappers with JSR 330 annotations
If you have multiple mappers and all of them should be beans, then you can simply add one compiler argument in configuration and all the mappers will have @Singleton and @Named annotations by default.
Recently at TouK we had a one-day hackathon. There was no main theme for
it, you just could post a project idea, gather people around it and hack
on that idea for a whole day - drinks and pizza included.
My main idea was to create something that could be fun to build and be
useful somehow to others. I’d figured out that since Confitura was just
around a corner I could make a game, that would be playable at TouK’s
booth at the conference venue. This idea seemed good enough to attract
Rafał Nowak @RNowak3 and Marcin Jasion
@marcinjasion - two TouK employees, that with me
formed a team for the hackathon.
The initial plan was to develop a simple mario-style game, with
preceduraly generated levels, random collectible items and enemies. One
of the ideas was to introduce Confitura Man as the main character, but
due to time constraints, this fall through. We’ve decided to just choose
a random available sprite for a character - hence the onion man :)
How the game is played?
Since we wanted to have a scoreboard and have unique users, we’ve
printed out QR codes. A person that would like to play the game could
pick up a QR code, show it against a camera attached to the play booth.
The start page scanned the QR code and launched the game with username
read from paper code.
The rest of the game was playable with gamepad or keyboard.
Technicalities
Writing a game takes a lot of time and effort. We wanted to deliver, so
we’ve decided to spend some time in the days before the hackathon just
to bootstrap the technology stack of our enterprise.
We’ve decided that the game would be written in some Javascript based
engine, with Google Chrome as a web platform. There are a lot of HTML5
game engines - list of html5 game engines and you could easily create a
game with each and every of them. We’ve decided to use Phaser IO
which handles a lot of difficult, game-related stuff on its own. So, we
didn’t have to worry about physics, loading and storing assets,
animations, object collisions, controls input/output. Go see for
yourself, it is really nice and easy to use.
Scoreboard would be a rip-off from JIRA Survivor
with stats being served from some web server app. To make things harder,
the backend server was written in Clojure. With no experience in that
language in the team, it was a bit risky, but the tasks of the server
were trivial, so if all that clojure effort failed, it could be
rewritten in something we know.
Statistics
During the whole Confitura day there were 69 unique players (69 QR codes
were used), and 1237 games were played. The final score looked like
this:
Barister Lingerie 158 - 1450 points
Boilerdang Custardbath 386 - 1060 points
Benadryl Clarytin 306 - 870 points
And the obligatory scoreboard screenshot:
Obstacles
The game, being created in just one day, had to have problems :) It
wasn’t play tested enough, there were some rough edges. During the day
we had to make a few fixes:
the server did not respect the highest score by specific user, it was just overwritting a user’s score with it’s latest one,
there was one feature not supported on keyboard, that was available on gamepad - turbo button
server was opening a database connection each time it got a request, so after around 5 minutes it would exhaust open file limit for MongoDB (backend database), this was easily fixed - thou the fix is a bit hackish :)
These were easily identified and fixed.
Unfortunately there were issues that we were unable to fix while the
event was on:
google chrome kept asking for the permission to use webcam - this was very annoying, and all the info found on the web did not work - StackOverflow thread
it was hard to start the game with QR code - either the codes were too small, or the lighting around that area was inappropriate - I think this
issue could be fixed by printing larger codes,
Technology evaluation
All in all we were pretty happy with the chosen stack. Phaser was easy
to use and left us with just the fun parts of the game creation process.
Finding the right graphics with appropriate licensing was rather hard.
We didn’t have enough time to polish all the visual aspects of the game
before Confitura.
Writing a server in clojure was the most challenging part, with all the
new syntax and new libraries. There were tasks, trivial in java/scala,
but hard in Clojure - at least for a whimpy beginners :) Nevertheless
Clojure seems like a really handy tool and I’d like to dive deeper into
its ecosystem.
To run the server you need to have a local MongoDB installation. Than in
server’s directory run:
$ lein ring server-headless
This will start a server on http://localhost:3000
To run the game you need to install dependencies with bower and than
run
$ grunt
from game’s directory.
To launch the QR reading part of the game, you enter
http://localhost:9000/start.html. After scanning the code you’ll be
redirected to http://localhost:9000/index.html - and the game starts.
Conclusion
Summing up, it was a great experience creating the game. It was fun to
watch people playing the game. And even with all those glitches and
stupid graphics, there were people vigorously playing it, which was
awesome.
Thanks to Rafał and Michał for great coding experience, and thanks to all the players of our stupid little game. If you’d like to ask me about anything - feel free to contact me by mail or twitter @zygm0nt
Recently at TouK we had a one-day hackathon. There was no main theme for
it, you just could post a project idea, gather people around it and hack
on that idea for a whole day - drinks and pizza included.
My main idea was to create something that could be fun to build and be
useful somehow to others. I’d figured out that since Confitura was just
around a corner I could make a game, that would be playable at TouK’s
booth at the conference venue. This idea seemed good enough to attract
>Conclusion
