hello scala

The “Hello, Scala” paperback is just $10 alvin November 29, 2019 - 11:00am

November 29, 2019: A few days ago I made the PDF version of “Hello, Scala” free, and today I made the paperback version of “Hello, Scala” available again, and reduced it’s price from $20 to just $10. Click the image below to buy the book on Amazon.

As I’ve noted before, the contents of this book are being updated and improved, and in the future it will be available as Scala Book. The HTML version of those contents are currently available on the docs.scala-lang.org site.

“Hello, Scala” PDF is now free alvin November 26, 2019 - 5:31pm

November 26, 2019: The PDF version of my book “Hello, Scala” is now free, and you can download it by clicking on the image below.

Future “updated and improved” versions of the book are being released as Scala Book. Currently an HTML version of the book is available here on the scala-lang.org website, and we’ll have PDF, MOBI, and ePub versions of that available once the creation process is automated and a few other issues are resolved.

But for now, click on the image below if you’d like to download the PDF of Hello, Scala for free:

Hello, Scala PDF

An introduction to Akka Actors

Table of Contents1 - An Akka “Hello, world” example2 - A second example3 - More examples4 - Where Akka fits in5 - Source code6 - Key points7 - See also

This is an excerpt from my book, Hello, Scala. In this lesson I’ll show two examples of applications that use Akka actors, both of which can help you get started with my larger “Alexa written with Akka” = Aleka application.

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An Akka “Hello, world” example

First, let’s look at an example of how to write a “Hello, world” application using Akka.

Writing a “Hello” actor

An actor is an instance of the akka.actor.Actor class, and once it’s created it starts running on a parallel thread, and all it does is respond to messages that are sent to it. For this “Hello, world” example I want an actor that responds to “hello” messages, so I start with code like this:

Hello, Scala (free preview)

Note: The print version of Hello, Scala on Amazon will be going up to $20 (USD) this Saturday, April 13, 2019. It’s currently just $10, so you know, buy it while it’s on sale and all that. :)

If you like free things, here’s a link to a free preview (PDF) of the new version of my book, “Hello, Scala.” The book is 257 pages long, and the free preview contains the first 120 pages of it, so I hope it’s a significant preview.

July, 2019 Update: Hello, Scala was previously available in PDF and Kindle versions, but hopefully there are some big changes coming, so those versions are no longer for sale.

We Said Hello, Goodbye (Don’t Look Back)

Sorry I haven’t written much this week, I’ve been working on designs for the cover of a new book. But I can share one thing, my favorite song of the week, We Said Hello, Goodbye (Don’t Look Back), by Phil Collins. Some of the lyrics:

Well it really don’t matter much where you are
’cause home is in your heart
It’s a feeling that you wake with one day
Some people keep running all of their life
And still find they haven’t gone too far
They don’t see it's the feeling inside
The feeling inside.

Hello, Scala book (an introduction to Scala book)

July, 2019: Hello, Scala, is now available only in print form:

It was previously available in PDF and Kindle format, but there are some big changes planned, so those versions have been removed for the time being.

As the subtitle of the book shows, the purpose of this book is to help you learn the Scala programming language with small, easy lessons. The book consists of a little over 50 lessons, and it’s 258 pages long.