Top 10 Reasons Java Programs Envy Scala (Presentation)

Posted on September 20, 2015 by Graham Lea

From the archive: Originally posted in October 2011, I was reminded today of this post from my old blog, Graham Hacking Scala. I thought I should bring it over and give it a bit of a refresh…

In October 2011, I presented a talk at the 2nd meeting of the (then) new ScalaSyd Meetup. I talked through the “Top 10 Reasons Java Programs Envy Scala” in an attempt to give Java developers a taste of some little things that could make them much more productive if they switch to Scala.

Interestingly, in almost 4 years, very little has changed. Yes, Java 8 now has lambdas, but the standard collections library still makes very little use of them, forcing you to convert any collection to a stream before lambdas can be used, and pretty much nothing else mentioned in the talk has made its way into Java SE. People are still writing up lists of how to use Java better, but the fact is that a lot of Java best practices are either built into or easier to achieve in Scala.

Anyway, if you want get the real scoop on Java vs Scala and hear what all the Scala kids are raving about:

hit play on the SoundCloud recording below, and then
follow your way through the Prezi below that.

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Do you even know the first thing about REST?

Posted on January 23, 2015 by Graham Lea

It’s not unusual to see examples where people think they are “doing REST”, but are not. A lot of people are trying to use simple web technologies in their microservice architectures, but I suspect there’s a prevalent idea that if you are using HTTP and sending JSON back and forth, you’re doing REST, which is simply not the case. (We’re talking about the Representational State Transfer style of software architecture here, in case you’re lost.)

Spring’s REST

Spring’s Web MVC Framework documentation says in the first paragraph: “With the introduction of Spring 3.0, the @Controller mechanism also allows you to create RESTful Web sites and applications…” Further on, introducing its @RestController interface, it says: “It’s a very common use case to have Controllers implement a REST API, thus serving only JSON, XML or custom MediaType content.” So, does creating a web service using a @RestController-annotated class magically make it a RESTful service?
No. Such no.

Not so REST

The big thing I see developers getting wrong when trying to use web technologies for inter-service communication is that they continue to think about operations. Continue reading →

RxJava Threading Examples

Posted on July 3, 2014 by Graham Lea

I recently used RxJava while creating an add-on for Stash, the Git repository management tool from Atlassian. The plugin’s called “Who’s the Expert?” and it analyses commits to a repository to help answer two questions:

“Who has contributed the most to this project over the past few years?” and
“Who has made the most significant changes in recent months?”

A Problem Worthy of RxJava’s Attention

In order to achieve this, the plugin has to process a lot of data: it pulls all commits on the default branch for the last 2.5 years and analyses the content of every single one. I knew two things about this code in advance: first, there were going to be a lot of steps to go from a repository name to a leaderboard of the most influential committers, and second, I was pretty certain I’d need some multi-threading mojo in order to get it to perform in an acceptable time frame.
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Graham’s Guide to Learning Scala

Posted on November 23, 2012 by Graham Lea

From The Archives: This article is one of the all-time most popular posts from my previous blog Graham Hacking Scala. I thought it worth updating and re-printing it here.

It’s a pretty widely-accepted view that, as a programmer, learning new languages is a Good Idea™ . Most people with more than one language under their belt would say that learning new languages broadens your mind in ways that will positively affect the way you work, even if you never use that language again.

With the Christmas holidays coming up and many people likely to take some time off work, this end of the year presents a great opportunity to take some time out from your week-to-week programming grind and do some learning.

With that in mind, I present “Graham’s Guide to Learning Scala”. There are many, many resources on the web for learning about Scala. In fact, I think there’s probably too many! It would be quite easy to start in the wrong place and quickly get discouraged.

So this is not yet another resource to add to the pile. Rather, this is a guided course through what I believe are some of the best resources for learning Scala, and in an order that I think will help a complete newbie pick it up quickly but without feeling overwhelmed.

And, best of all, it has 9 Steps!