Java SDK Installation Guide

The Fluvio Java library should work with any version of Java greater than version 8, but we have specifically tested it on Java 8, 11, 15, 16, and 17. In order to see whether you have the Java Development Kit (JDK) installed and to see what version it is, run the following:

$ javac --version
javac 16.0.1      # You might have something different

If you don’t already have a JDK installed, visit the Oracle website in order to download it. Choose the link for your platform, then run the installer and follow the instructions. When the installation is complete, double-check that you can execute Java from the command line:

$ javac --version

There are two environment variables we need to make sure are right, your PATH and another one called JAVA_HOME. If you were already able to execute javac --version, you can skip this extra PATH setup, but you may still need to set up JAVA_HOME.

 

Setup PATH and JAVA_HOME

If you still can’t execute javac, you may need to update your PATH. Make sure you remember where you installed your JDK. We’ll give examples of common locations where it might get installed below. To update these variables, we’ll update a file called ~/.bashrc.

On Mac, we’ll add a line to the end of your ~/.bashrc that looks something like this:

export PATH="/Library/Java/JavaVirtualMachines/jdk-16.0.1.jdk/Contents/Home/bin:${PATH}"
export JAVA_HOME="/Library/Java/JavaVirtualMachines/jdk-16.0.1.jdk/Contents/Home"

On Linux, “installing” Java essentially amounts to unzipping the download file in a particular directory. I tend to put the JDK right into the home directory, e.g. ~/jdk1.8.0_181/. Wherever you unzipped your JDK, you’ll want to use that path when setting the following variables in ~/.bashrc:

export PATH="${HOME}/jdk1.8.0_181/bin:${PATH}"
export JAVA_HOME="${HOME}/jdk1.8.0_181/"

 

Install Gradle

Gradle is a build tool that we’ll be using for this project. It will help us to download the Fluvio library and compile everything correctly. [Visit the gradle website] to download and install it. When you’re done, you should be able to run the gradle --version command.

Visit the gradle website

 

Setting up the project for Fluvio development

Now we’re going to use gradle to help us set up the project. Let’s create a new directory for the project:

$ mkdir fluvio-java-app && cd fluvio-java-app

Run gradle init inside the directory:

$ gradle init

Select type of project to generate:
  1: basic
  2: application
  3: library
  4: Gradle plugin
Enter selection (default: basic) [1..4] 2

Select implementation language:
  1: C++
  2: Groovy
  3: Java
  4: Kotlin
  5: Scala
  6: Swift
Enter selection (default: Java) [1..6] 3

Split functionality across multiple subprojects?:
  1: no - only one application project
  2: yes - application and library projects
Enter selection (default: no - only one application project) [1..2] 1

Select build script DSL:
  1: Groovy
  2: Kotlin
Enter selection (default: Groovy) [1..2] 1

Select test framework:
  1: JUnit 4
  2: TestNG
  3: Spock
  4: JUnit Jupiter
Enter selection (default: JUnit 4) [1..4] 1

Project name (default: java): fluvio-java-app
Source package (default: fluvio.java.app):

> Task :init
Get more help with your project: https://docs.gradle.org/7.0/samples/sample_building_java_applications.html

BUILD SUCCESSFUL in 31m 43s
2 actionable tasks: 2 executed