JDK Prerequisite

Owned by Megan Ellis
Aug 23, 2022
4 min read

You must install the supported version of OpenJDK Java Development Kit (JDK) before installing frevvo. The Insight Server requires the JAVA_HOME environment variable to be set to the installation directory for the Java package that you install.

This page refers specifically to a JDK installation on a Windows system. If you are installing on Unix you will need to adjust some of the specifics accordingly.

Follow the steps below:

 On This Page:

 

Check to see if JDK is already installed

If you are not sure whether you have the supported version of JDK installed correctly, please confirm by doing the following:

  1. Run a complete directory search  for the JDK

    1. Run a complete directory search(using the 'All File and Folders' option if available) on your drives for the occurrence of 'jdk' in the filename to search for the JDK.

      1. If your results retrieve a folder with the name 'jdk' immediately followed by a series of version numbers (for example, jdk-11.0.2), then your JDK has been installed. You should double-check the contents of this folder to ensure that the installation files are intact. If you are unsure about this, proceed to Install JDK section to re-install it. Otherwise, proceed to step 4 in that section to check that your JAVA_HOME environment variable has been set correctly.
    2. If you do not retrieve results as explained above, then it is highly likely that your JDK has not been installed. Go to the applicable installation section below for the instructions.

Install JDK

 To install JDK, follow these instructions:

  1. Download the supported version of Java JDK. There are several vendors who source the supported JDK version as OpenJDK. Here is a suggested resource: Adopt OpenJDK (select the JVM HotSpot and the correct OpenJDK version). For more information about selecting an OpenJDK vendor see this article.
  2. Download the supported JDK version.
  3. When the download has finished, run the Java installer. At one point, you will be asked to choose a directory to install to. Make note of this directory for use later.
  4. Check that the JAVA_HOME environment variable has been set correctly.
    1. Open the 'Start' menu, choose 'Run', type cmd in the 'Run' dialog box, and click the 'OK' button.
    2. In the command prompt window, type echo %JAVA_HOME% and then press Enter.
    3. View the result:
    4. If a directory path is displayed that looks similar to one of the following examples, with the letters 'jdk' immediately preceding a series of version numbers, and this path matches the location where you installed the JDK in step 3, then your JDK has been successfully installed and your JAVA_HOME environment variable has been set correctly. ''Examples of typical JAVA_HOME environment variable values'':

      • C:\Program Files\Java\jdk11.0.2
      • C:\Progra~1\Java\jdk11.0.2_9
      • C:\Java\jdk11.0.2_9
      • C:\jdk11.0.2

    5. If nothing is displayed or you do not see 'jdk' immediately followed by a series of version numbers (like one of the examples above), then you need to set the JAVA_HOME environment variable. Please follow these instructions to set your JAVA_HOME environment to the directory where you have just installed the JDK. By default, this directory is under C:\Program Files(x86)\Java for a 32-bit Windows System. You will find it under c:\Program Files on a 64 bit Windows system.

Mac & Linux OS

The above instructions are intended for installation on a PC. For customers using Mac or Linux OS, the steps may vary depending on your OS configuration. Here is an example of steps to install JDK on a Mac using Homebrew.

 Click to expand Mac installation steps...
  1. Type the command prompt: brew tap adoptopenjdk/openjdk
  2. Type the command prompt: brew search adoptopenjdk. This lists available jre/jdk versions
  3. Find the version you want to install, ex. adoptopenjdk11-jre.
  4. Type the command prompt: brew install adoptopenjdk11-jre
  5. Type the command prompt: ls -lsa /Library/Java/JavaVirtualMachines/
    1. Confirm java was installed.
  6. Type the Command prompt: java -version
    1. Confirm the version being used.

The command you use will depend on what Linux distribution you use. For example, Fedora uses dnf, OpenSUSE uses zypper, Debian and Ubuntu use apt, Slackware uses sbopkg, FreeBSD uses pkg_add, and Illumos-based OpenIndiana uses pkg. Please refer to the appropriate OS documentation for the correct command(s).

Visit the OpenJDK documentation or the AdoptOpenJDK documentation for more details.

Locate the JDK Installation Directory 

If you already know the installation path for the Java or Software Development Kit, go to the Set the JAVA_HOME Environment Variable section below. Otherwise, find the installation path by following these instructions:

  1. Unless you changed the installation path for the Java Development Kit during installation, it will be in a directory under C:\Program Files(x86)\Java for a 32 bit architecture and under c:\Program Files for a 64 bit Windows system. Using Explorer, open the directory C:\Program Files(x86) or Program Files\Java.
  2. Inside that path will be one or more subdirectories such as jdk11.0.2. If you have just installed the Java Development Kit, it will be installed to the newest directory, which you can find by sorting by date. For example, it may be installed in C:\Program Files\Java\jdk11.0.2. This is the installation path.

Set the JAVA_HOME Environment Variable

Once you have identified the JDK installation path:

  1. Open the Control Panel.
  2. Click the System icon
  3. Click Advanced System Settings.
  4. Click the Environment Variables button.
  5. Under System Variables, click New.
  6. Enter the variable name as JAVA_HOME.
  7. Enter the variable value as the installation path for the Java Development Kit.
  8. Click 'OK'.
  9. Click 'Apply Changes' or 'OK'

Return to Quick Start Installation Guide for frevvo in house if you are evaluating frevvo or to Database Setup if you are configuring an external database in your in-house environment.