$schemamarkup = get_post_meta(get_the_ID(), 'schemamarkup', true); if(!empty($schemamarkup)) { echo $schemamarkup; }

How to Install OpenJDK on Ubuntu 18.04 Bionic Gnu/Linux

May 20, 2018 | By the+gnu+linux+evangelist.

Java 12

    OpenJDK 12 Ubuntu 18.04 Installation Guide