title: Java won't install on Ubuntu
body: <p>I have begun working of building a custom Android HAL. In order to do this I am setting up a new Linux install and had an error when trying to run make.</p>
  
  <pre><code>make could not find jdk tools.jar
  </code></pre>
  
  <p>After digging around forums and attempting to solve this problem I tried to uninstall Java and reinstall it. Now when I type this:</p>
  
  <pre><code>java -version
  </code></pre>
  
  <p>I get this error:</p>
  
  <pre><code>Command 'java' not found, but can be installed with:....
  </code></pre>
  
  <p>This suggests it's uninstalled. However, when I go to install with </p>
  
  <pre><code>sudo apt install openjdk-11-jre-headless
  </code></pre>
  
  <p>I get told this:</p>
  
  <pre><code>openjdk-11-jre-headless is already the newest version (10.0.1+10-3ubuntu1).
  </code></pre>
  
  <p>So obviously somewhere it thinks it's still installed but I have no idea how to resolve this.</p>