Running a Minecraft Server With Docker

Sun Feb 28 2021

Close your eyes for one moment and imagine that everything you host runs in docker containers. You no longer need to battle system dependencies, and configurations are more manageable; it is now easier to backup and transfer your applications.

In my quest to dockerize everything, I am now dockerizing my Minecraft server. Minecraft is a relatively simple application to host since it is just a single Java application that you need to run. To put this in Docker, we need to declare a Java Docker image that launches our Minecraft server.

FROM openjdk:8u232

WORKDIR /root/minecraft

CMD java -Xmx2048M -jar spigot-1.10.jar -o true

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Running Scala Code in Docker

Sat Feb 13 2021

Alrighty, folks, this blog post is pretty straightforward from the title. We are going to be running Scala code in Docker containers. Specifically, we will be using SBT and docker-compose. SBT is a built tool primarily used by Scala developers, and docker-compose is a tool for defining docker environments.

To start, we need to create a simple Docker container that can build our scala code. From an existing Java JDK container, SBT is straightforward to install from a package manager.

FROM openjdk:8u232

ARG SBT_VERSION=1.4.1

# Install sbt
RUN \
  mkdir /working/ && \
  cd /working/ && \
  curl -L -o sbt-$SBT_VERSION.deb https://dl.bintray.com/sbt/debian/sbt-$SBT_VERSION.deb && \
  dpkg -i sbt-$SBT_VERSION.deb && \
  rm sbt-$SBT_VERSION.deb && \
  apt-get update && \
  apt-get install sbt && \
  cd && \
  rm -r /working/ && \
  sbt sbtVersion

RUN mkdir -p /root/build/project
ADD build.sbt /root/build/
ADD ./project/plugins.sbt /root/build/project
RUN cd /root/build && sbt compile

EXPOSE 9000
WORKDIR /root/build

CMD sbt compile run

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Parallel Java Performance Overview

Fri Aug 07 2020

More cores = better performance, simple maths. Although it makes intuitive sense that more processing power would be advantageous, that is not always the case. There are multiple implementation paradigms and libraries for making a program run parallel; you have parallel streams, threads, and thread pools. However, there is no clear cut winner because many factors affect parallel program performance: the number of tasks, IO, amount of work in each task. This post aims to review the significant paradigms and factors affecting multi-threaded performance by looking at empirical data generated in Java. Additionally, topics like NQ and Amdahl’s law are examined within the context of the experiments presented.

1 Single Threaded

To gain ground for comparison, we establish a baseline task to get performed. We want to execute a list of tasks and store the results in a collection. On a single thread, this is merely a traversal with a mapping.

@Override
public List<E> runTasks(Vector<Work<E>> tasks)
{
    return tasks.stream()
        .map(Work::runTask)
        .collect(Collectors.toList());
}

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Fun With Functional Java

Mon Jul 13 2020

It’s time I tell you all my un-popular opinion: Java is a fun language. Many people regard Java as a dingy old language with vanilla syntax. Please don’t fret; I am here to share the forbidden knowledge and lure you into the rabbit hole that is functional programming esque syntax in Java. And yes, this goes way beyond merely having lambda statements.

1 Ways to create a list

The plain old way of making a list would look something like this:

List<Integer> myList = new ArrayList<Integer>();
myList.add(1);
myList.add(2);
myList.add(3);

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Gremlin in 10 Minutes

Sat Jul 28 2018

1 What is Gremlin?

Gremlin is a graph traversal language: think of Gremlin as the SQL for graph databases. Gremlin is not a graph database server, it is a language; but, there is a Gremlin Server and a Gremlin Console available for interacting with graph databases. It is possible to use Gremlin on large database platforms like Titan and HBase.

2 Graph Data Base Basics

A graph database is based on graph theory. A graph is composed of nodes, edges, and properties. A key object/component in a graph database is stored as a node. Nodes are connected via edges representing relationships. For example, you may represent people as nodes and have edges representing friendships. You can assign properties to both nodes and edges. A person (node) may have the properties of age and name, where a friendship (edge) may have a start date property.

2.1 Why Graph Databases?

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