title: The program 'jshell' is currently not installed when trying to run jshell on Ubuntu
body: <p>I have downloaded and "manually" installed JDK 10 for Linux 64bit edition (for Ubuntu 16.04),
  <a href="http://www.oracle.com/technetwork/java/javase/downloads/jdk10-downloads-4416644.html" rel="nofollow noreferrer">Oracle Java SE Development Kit</a>
  (note: I wanted to download the Java9 JDK but this is no longer supported and I was referred to the Java 10 SE Development kit instead). </p>
  
  <p>When I try running <code>jshell</code> from a terminal window I get the following error,</p>
  
  <blockquote>
    <p>The program 'jshell' is currently not installed. To run 'jshell'
    please ask your administrator to install the package
    'openjdk-9-jdk-headless' You will have to enable the component called
    'universe'</p>
  </blockquote>
  
  <p><a href="https://i.stack.imgur.com/bdnMt.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bdnMt.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/L9mPB.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/L9mPB.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/Ouw47.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ouw47.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/bCcWm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bCcWm.png" alt="enter image description here"></a></p>
  
  <p>I dont know why the message is asking me to install openjdk when I have installed the classic java version. When I run "which jshell" I dont get any details returned.</p>
  
  <p>Can anyone help me get <code>jshell</code> installed and working ?</p>