We open a terminal and look for the location of java:
manuel@zonademanel:~ ? whereis java
java: /usr/bin/java /etc/java /usr/bin/X11/java /usr/share/java /usr/share/man/man1/java.1.gz
What we are looking for is /usr/bin/java continue on the command line to find the absolute path , as this is only a symbolic link.
manuel@zonademanel:~ ? ls -lah /usr/bin/java
lrwxrwxrwx 1 root root 22 may 19 2015 /usr/bin/java -> /etc/alternatives/java
manuel@zonademanel:~ ? ls -lah /etc/alternatives/java
lrwxrwxrwx 1 root root 39 dic 7 11:52 /etc/alternatives/java -> /usr/lib/jvm/java-8-oracle/jre/bin/java
I modified my /etc/environment file with the following values
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/usr/lib/jvm/java-8-oracle/jre/bin" JAVA_HOME="/usr/lib/jvm/java-8-oracle/jre"
If I do not want to relogin I can reload the changes with:
source /etc/environment
??And run mvn -version correctly
manuel@zonademanel:~ ? mvn -version
Apache Maven 3.0.5
Maven home: /usr/share/maven
Java version: 1.8.0_77, vendor: Oracle Corporation
Java home: /usr/lib/jvm/java-8-oracle/jre
Default locale: es_MX, platform encoding: UTF-8
OS name: "linux", version: "3.16.0-70-generic", arch: "amd64", family: "unix"