The latest expert opinions, articles, and guides for the Java professional.

Get ready for the next wave of JRebel for Android features

We recently released JRebel for Android 1.0. The feedback from the community has been great and we are working hard on delivering even more value for all users. Today we are excited to reveal a few features that we have been tinkering with since the release.

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Looking back at 2015 and Happy 2016!

Another year is coming to its logical conclusion and we’re extremely happy to welcome the upcoming 2016. New Year’s Eve is the perfect time to look back at RebelLabs achievements from the year and make plans for the future.

2015 was a great year, we worked hard on creating the best technical, yet opinionated content for you. So not only would you learn something or refresh the knowledge about Java, but also get a chance to look at technology from a different point of view or solidify your opinions with more arguments.

Hopefully we did a great job and you learn a thing or two and enjoyed reading us.

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Programming Language Development Made Easy by Sven Efftinge & Miro Spönemann

The last Virtual JUG presentation session of 2015 was all about programming language development, both general purpose and domain specific languages or DSLs. We had the amazing duo of speakers that commit a large chunk of their time into the development on a language development framework, called Xtext. You might have heard of it,  because it was behind the Xtend language that unconventionally compiles into Java rather than JVM bytecode.  

The combination of Sven Efftinge and Miro Spönemann delivered a brilliant presentation on how general programming languages get developed, including a real demo showing how to build a small programming language, together with integrations with Java and the tooling support for the IDEs. All that in around 50 minutes! What a time to be alive!

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Profiling RESTful Services with XRebel


Application developers can test applications that have RESTful endpoints and see the performance metrics using XRebel, the performance tool for Java development.

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Exploring the virtues of microservices with Play and Akka

Let’s talk about microservices. This is a fairly well hyped topic about the architecture of software systems, but I don’t want to dive into a discussing the rights and wrongs of the debate on whether microservices are the bee’s knees or just another reincarnation of service oriented architecture, SOA.

Instead, in this first post of a series on microservices I want to look at the qualities that make microservices important and how various frameworks or technology stacks play nicely together.

So today we’ll talk about the features that make a microservices architecture possible and how Typesafe’s stack with Play framework and Akka, the toolkit for message-driven applications, enable these features. Maybe they don’t, or maybe there are other stacks that do it better. For now we plan to explore the microservices landscape for a while, so stay with us and suggest where to look next to investigate your favorite frameworks.

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Announcing JRebel for Android 1.0 — Android Development Awakens!

Have you been naughty or really naughty this year?

Mutation Testing in Java with pitest by Henry Coles

Henry Coles

The latest Virtual JUG session was about a somewhat mystical and intriguing subject: mutation testing! Luckily for us, the speaker we had is one of the world class experts on the topic –Henry Coles.

Henry is the Head of Innovation at NCR, in Edinburgh. For the last 15 years he’s been working at becoming a better software engineer and has been developing award winning systems in industries ranging from energy trading and smart metering through to life insurance and finance.

You can find him on Twitter: @0hjc and ask all the questions about the session, about mutation testing, code and tests quality and software engineering in general.

He is also the author of the mutation testing library for Java, pitest. So, Henry has vast experience and knowledge of the matters involved and was generous enough to share his expertise with us in this session.

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Java 8 Best Practices Cheat Sheet

RebelLabs Java 8 cheat sheet

Java 8 has already been with us for quite some time. Let’s reflect on it and talk about the best practices that have naturally grown in its typical usage.

In this post we’ll look at the hot topics of the Java 8 language: default methods, lambdas and streams and using Optional to represent absent values.

We hope this post can give you an idea of some of the best practices on using Java 8 features and still have readable and maintainable code. If you liked it, don’t forget to print the handy 1 page cheat sheet we prepared with the takeaways from the post so you can print it out and put it under your less experienced colleague’s coffee cup.

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A Fluent API or not a fluent API? That is the Question!

Fluent API or not?

Nowadays with the variety of programming languages available to you, it’s tough to stick to the coding rules of your favorite choice without looking at what else is available.

I have been a professional Java developer for many years now, but I’m keen to always look at what is being done in the industry by all kinds of actors and I have to admit to something: there is cool stuff out there, in other programming languages. The cool stuff isn’t just the features or syntactic sugar constructs, but it’s also the coding standards that get my attention. In this post I want to talk about fluent APIs.

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