In this post, we will see how to get started with January on the command line.

Requirements

• Knowing how to use vi or any other command line editor
• Havin maven installed
  • On Windows: https://www.mkyong.com/maven/how-to-install-maven-in-windows/
  • On Linux: apt install maven

How-to

1. Go into the directory you want to create your project in and execute following command:

   mvn archetype:generate \
   -DgroupId=com.test \
   -DartifactId=mvnExample \
   -DarchetypeArtifactId=maven-archetype-quickstart \
   -DinteractiveMode=false
   

   This may take some time if it is the first time you use Maven. After the execution of the command you can move into the newly created folder and see the folders and files of the project.

2. Now you have to add the January dependency to you project, in order to do that edit the pom.xml file with vi or whatever you prefer. You have to add following code between the two ‘dependencies’ tags:

   <dependency>
       <groupId>com.github.yannick-mayeur</groupId>
       <artifactId>org.eclipse.january</artifactId>
       <version>2.0.2</version>
   </dependency>
   

3. You can now add some code that uses the January library into the App.java file at src/main/java/com/test. Here is some example code:

   Dataset dataset = DatasetFactory.createFromObject(new double[] { 1,2, 3, 4, 5, 6, 7, 8, 9 });
   // Print the output:
   System.out.println("shape of dataset: " + Arrays.toString(dataset.getShape()));
   System.out.println("toString of dataset: " + dataset.toString());
   System.out.println("toString, with data, of dataset: \n" + dataset.toString(true));
   

   Don’t forget to import the relevant libraries:

   import java.util.Arrays;
   import org.eclipse.january.dataset.Dataset;
   import org.eclipse.january.dataset.DatasetFactory;
   

4. You can then compile the project with mvn clean package and execute it with
   mvn exec:java -Dexec.mainClass="com.test.App"