title: “An error has occurred. See the log file..” problem to install eclipse on Ubuntu 18.04.4 LTS
body: <p>I installed eclipse on Ubuntu 18.04.4 LTS but can't open ecilpse. An error message pop up.</p>
  
  <p>error message:</p>
  
  <pre><code>An error has occurred.  See the log file /home/sumon/.eclipse/org.eclipse.platform_3.8_155965261/configuration/1582634683890.log
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/V1yIG.png" rel="nofollow noreferrer">error message screenshot. </a></p>
  
  <p>log file:</p>
  
  <pre><code>sumon@sumon-Vostro-1450:~$ cat /home/sumon/.eclipse/org.eclipse.platform_3.8_155965261/configuration/1582634683890.log
  !SESSION Tue Feb 25 18:44:43 BDT 2020 ------------------------------------------
  !ENTRY org.eclipse.equinox.launcher 4 0 2020-02-25 18:44:43.927
  !MESSAGE Exception launching the Eclipse Platform:
  !STACK
  java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter
      at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:471)
      at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:588)
      at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
      at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:626)
      at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
      at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
      at org.eclipse.equinox.launcher.Main.main(Main.java:1414)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/dibmh.png" rel="nofollow noreferrer">log file screenshot.</a></p>
  
  <p>How to solve this problem? I like to mention that I installed another version of eclipse before and uninstall this.</p>