Update info - how to currently set Java_home?

I'am trying to get Maven running. I have installed JDK and Maven. Thus I have been trying to set the Java_home variable for three days now, I cannot get it working.

I have followed the instructions of another askUbuntu Topic:

• How to set JAVA_HOME for Java?
• How to set Maven home PATH on Ubuntu as User

This doesn't work. Not any explanation explains how to set the path, they rather give examples how to set their path.. So I have no idea whats wrong with mine, it is the location to the file in the etc/environment.

I installed maven by downloading the correct latest version on the site. Extracted and installed it in opt directory using known sudo-commands.

I created the maven.sh file myself, since there wasn't a file like this in the profile.d directory. You can see how I set that in the cat output and the picture below.

The Java_Home set in my etc/environement though is: JAVA_HOME="/usr/lib/jvm/java-11-openjdk-amd64";This used to be /usr/opt/jdk-13.0.1 (which you will see the terminal give back the first time), because thats how I thought It needed to work according to explanation how to install Maven.

When I source my maven.sh, I get the right mvn -version in the terminal. When I close terminal, I have to source it again.

Here my terminal feedback on the versions, rember that after the first 3 commands (version -java, -mvn and echo) I source my maven.sh file manually:

mussche@MuskiProBook:~$ java -version
openjdk version "11.0.11" 2021-04-20
OpenJDK Runtime Environment (build 11.0.11+9-Ubuntu-0ubuntu2.20.04)
OpenJDK 64-Bit Server VM (build 11.0.11+9-Ubuntu-0ubuntu2.20.04, mixed mode, sharing)

mussche@MuskiProBook:~$ mvn -version
The JAVA_HOME environment variable is not defined correctly,
this environment variable is needed to run this program.

mussche@MuskiProBook:~$ echo $JAVA_HOME
/usr/opt/jdk-13.0.1

mussche@MuskiProBook:~$ java -version
openjdk version "11.0.11" 2021-04-20
OpenJDK Runtime Environment (build 11.0.11+9-Ubuntu-0ubuntu2.20.04)
OpenJDK 64-Bit Server VM (build 11.0.11+9-Ubuntu-0ubuntu2.20.04, mixed mode, sharing)

mussche@MuskiProBook:~$ mvn -version
Apache Maven 3.8.2 (ea98e05a04480131370aa0c110b8c54cf726c06f)
Maven home: /opt/maven
Java version: 11.0.11, vendor: Ubuntu, runtime: /usr/lib/jvm/java-11-openjdk-amd64
Default locale: nl_NL, platform encoding: UTF-8
OS name: "linux", version: "5.11.0-27-generic", arch: "amd64", family: "unix"

mussche@MuskiProBook:~$ echo $JAVA_HOME
/usr/lib/jvm/java-11-openjdk-amd64

mussche@MuskiProBook:~$ cat /etc/environment
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin"
JAVA_HOME="/usr/lib/jvm/java-11-openjdk-amd64"

mussche@MuskiProBook:~$ cat /etc/profile.d/maven.sh
export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
export M2_HOME=/opt/maven
export MAVEN_HOME=/opt/maven
export PATH=${M2_HOME}/bin:${PATH}

/etc/profile.d/maven.sh content:

How to install maven correct? How to set the variables, where to find the files that need to be changed, and exactly how to change them?

I solved the issue. I don't exactly why, but after several restarts (not after just one) the path got set instantly instead of me having to manually source it.

Kr,

Yannick

For ubuntu - to add Java-openJdk and Maven

1. Install OpenJDK through CLI
2. Move Maven and Gradle to /opt/

Working config for openjdk-17

sudo vim /etc/profile

export JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64
export PATH=$PATH:$JAVA_HOME/bin
export CLASSPATH=$JAVA_HOME/jre/lib/ext:$JAVA_HOME/lib/tools.jar

export GRADLE_HOME=/opt/gradle-8.1
PATH=$PATH:$GRADLE_HOME/bin

export MAVEN_HOME=/opt/apache-maven-3.9.1
PATH=$PATH:$MAVEN_HOME/bin

I saw one restart required, then check mvn --version