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A Scala “file find” utility

By Alvin Alexander. Last updated: September 9 2019

I wanted some specific features in a “find” utility, and when I couldn’t figure out how to get them with combinations of find, awk, and other Unix commands, I wrote what I wanted in Scala. Those features are (a) showing matching filenames, (b) showing the line that matches my search pattern, and underlining the pattern in the output, (c) showing the line numbers of the matches, and (d) showing an optional number of lines from the file before and after each match.

Some RxJava example source code (Hackers at Cambridge tutorials)

By Alvin Alexander. Last updated: March 3 2019

I recently watched the three Hackers at Cambridge Introduction to RxJava videos, and coded along with them. If you’re interested in some example RxJava code, here’s what I typed in.

The first thing you do is create a new Gradle/Java project with these commands:

mkdir MyProject
cd MyProject
gradle init --type java-application

With that project created you can begin creating some Java/RxJava code.

Beginning Java Game Development with LibGDX (source code)
URL
https://github.com/apress/beg-java-game-dev-w-libgdx
alvin December 28, 2017 - 9:17am

The source code for Beginning Java Game Development with LibGDX is at the URL shown.

Scalafmt, a source code formatter for Scala alvin October 28, 2017 - 2:15pm

Scalafmt is a source code formatter for Scala.

Show me your flowcharts and conceal your tables ...

By Alvin Alexander. Last updated: October 20 2017

“Show me your flowcharts (source code), and conceal your tables (domain model), and I shall continue to be mystified; show me your tables (domain model) and I won’t usually need your flowcharts (source code): they’ll be obvious.”

~ Fred Brooks, “The Mythical Man Month”

(text in parentheses added by me)

< back to my photo gallery
LaTeX and The Matrix alvin October 8, 2017 - 8:17pm

Sometimes I think working with LaTeX is like sitting at the controls of the Nebuchadnezzar in The Matrix.

A look at how the Scala `lazy val` syntax gets converted into Java code (bytecode)

By Alvin Alexander. Last updated: March 22 2019

Table of Contents

  1. A little `lazy val` conversion example
  2. A second `lazy val` conversion example
  3. One more `lazy val` conversion example
  4. The end
Table of Contents1 - A little `lazy val` conversion example2 - A second `lazy val` conversion example3 - One more `lazy val` conversion example4 - The end

I don’t have any major conclusions to share in this blog post, but ... what I was curious about is how Scala implements “lazy val” fields. That is, when the Scala code I write is translated into a .class file and bytecode that a JVM can understand, what does that resulting code look like?

How to format source code blocks in Scaladoc comments alvin June 10, 2017 - 4:38pm

As a quick note, if you want to embed a Scala source code example in your Scaladoc comments, just put the source code block in between {{{ and }}} characters in your comments, as shown in this example:

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