Prerequisites¶

Windows¶

The following software has to be installed locally:

Java Development Kit: for instance the Oracle Java SE Development Kit 13 or the OpenJDK
MQTT broker: for instance Eclipse Mosquitto or EMQ

Then make sure that the JAVA_HOME environment variable is set and points to your JDK installation.

Linux¶

The examples were tested under Ubuntu 18.04 using JDK 15 and Maven 3.6.0.

Note

During testing we noticed that there are several incompatibilities between the different Java and Maven versions. Therefore, a bit of trial and error might be required to get it running on a different system.

Getting the JDK

sudo add-apt-repository ppa:linuxuprising/java

sudo apt update

sudo apt install oracle-java15-installer

If you want to set up the new installed java as the default, you can also install the following package:

apt-get install oracle-java15-set-default

This will configure the required environment variables using a profile.d configuration file.

Note

Different shell applications handle profile.d differently. In the case of zsh the profile.d configuration path is not loaded at all. Therefore, the following lines should be added to your .zshrc file.

#JAVA PATHS
export J2SDKDIR=/usr/lib/jvm/java-15-oracle

export J2REDIR=/usr/lib/jvm/java-15-oracle

export PATH=$PATH:/usr/lib/jvm/java-15-oracle/bin:/usr/lib/jvm/java-15-oracle/db/bin

export JAVA_HOME=/usr/lib/jvm/java-15-oracle

export DERBY_HOME=/usr/lib/jvm/java-15-oracle/db

Getting Maven

apt-get install maven

Getting Mosquitto

sudo apt-get install mosquitto

Installation¶

Step I: Building the Java package and installing Lablink resources¶

To build the JAR file for the examples, under Windows issue the following command in the root directory of the examples package:

mvnw clean package

For Linux run:

mvn clean package

Note

This command will start Maven, a build automation tool for Java, in the background. It will compile the Java source files from subfolder src and put all generated outputs in a subfolder called target. The first time you run this script, all dependencies will be copied to your local system, which may take a while and produce a lot of output in your terminal. The build process is configured through the Project Object Model, which is stored in the pom.xml file

By default, this will also retrieve all other Lablink resources that are required to run the examples. More specifically, the following JAR files are copied to sub-folder target/dependency:

Configuration Server: config-0.1.0-jar-with-dependencies.jar
Datapoint Bridge: dpbridge-0.0.1-jar-with-dependencies.jar
Simple Sync Host: sync-0.0.1-jar-with-dependencies.jar

After successfull installation, also the Javadoc API documentation of the examples package is available (see index.html in subfolder target/site/apidocs).

Step II: Starting the configuration server¶

Start the configuration server by executing script run_config.cmd in subfolder scripts/0_config. For Linux, use the run_config.sh script. This will make the content of database file examples-config.db available via http://localhost:10101.

Note

Once the server is running, you can view the available configurations in a web browser via http://localhost:10101, see below.