The JAVA_HOME environment variable is not defined correctly This environment variable is needed to run this program NB: JAVA_HOME should point to a JDK not a JRE. Commands: nano etc/profile export JAVA_HOME="/usr/lib/jvm/jdk1.8.0_311" export PATH=$PATH:$JAVA_HOME/bin export JAVA_HOME=/usr/lib/jvm/jdk1.8.0_311 sudo gedit /etc/environment Add "JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64"" to /etc/environment Description of command: 1) This is the place to give the variable JAVA_HOME the value of the jdk. JDK from oracle is preferred. After editing the file, laptop should restart, so that the value will be set. 2, 3) This two line should be added. When we give this JAVA_HOME a path, this path will be global variable all around the Linux. 4) If after this also there is error: give 4th command to terminal: We need to update in other places as well. 5,6). We need to update in environment variable as well. Remark: This folder 'jdk1.8.0_311' is do...