title: Eclipse has an internal error during Launching
body: <p>I am facing this issue with eclipse (Its eclipse Oxygen) I am unable to run a simple Java program<br>
  This happen after I modified the project to be a Maven project.<br>
  what I tried so far:<br>
  I updated the software using (help > check for updates)<br>
  deleted the Workspace, and created a new one.  </p>
  
  <p><a href="https://i.stack.imgur.com/xzORu.png" rel="noreferrer"><img src="https://i.stack.imgur.com/xzORu.png" alt="printScreen"></a></p>
  
  <pre><code>!ENTRY org.eclipse.core.jobs 4 2 2017-12-21 13:15:48.670
  !MESSAGE An internal error occurred during: "Launching MailProcessor".
  !STACK 0
  java.lang.NullPointerException
      at org.eclipse.jdt.launching.JavaRuntime.isModularJava(JavaRuntime.java:1043)
      at org.eclipse.jdt.launching.JavaRuntime.isModularConfiguration(JavaRuntime.java:1020)
      at org.eclipse.jdt.launching.JavaRuntime.computeJREEntry(JavaRuntime.java:2341)
      at org.eclipse.m2e.jdt.internal.launch.MavenRuntimeClasspathProvider.computeUnresolvedClasspath(MavenRuntimeClasspathProvider.java:93)
      at org.eclipse.jdt.internal.launching.RuntimeClasspathProvider.computeUnresolvedClasspath(RuntimeClasspathProvider.java:57)
      at org.eclipse.jdt.launching.JavaRuntime.computeUnresolvedRuntimeClasspath(JavaRuntime.java:1509)
      at org.eclipse.jdt.launching.AbstractJavaLaunchConfigurationDelegate.getBootpathExt(AbstractJavaLaunchConfigurationDelegate.java:299)
      at org.eclipse.jdt.launching.AbstractJavaLaunchConfigurationDelegate.getVMSpecificAttributesMap(AbstractJavaLaunchConfigurationDelegate.java:615)
      at org.eclipse.jdt.launching.JavaLaunchDelegate._OT$callOrig(JavaLaunchDelegate.java:71)
      at org.objectteams.Team._OT$terminalCallNext(Team.java:598)
      at org.objectteams.Team._OT$callNext(Team.java:582)
      at org.eclipse.objectteams.otdt.internal.debug.adaptor.launching.JDTLaunchingAdaptor._OT$callNext(JDTLaunchingAdaptor.java:56)
      at org.eclipse.objectteams.otdt.internal.debug.adaptor.launching.JDTLaunchingAdaptor._OT$callReplace(JDTLaunchingAdaptor.java:56)
      at org.objectteams.Team._OT$callAllBindings(Team.java:557)
      at org.eclipse.jdt.launching.JavaLaunchDelegate.callAllBindings(JavaLaunchDelegate.java)
      at org.eclipse.jdt.launching.JavaLaunchDelegate.launch(JavaLaunchDelegate.java)
      at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:885)
      at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:739)
      at org.eclipse.debug.internal.ui.DebugUIPlugin.buildAndLaunch(DebugUIPlugin.java:1039)
      at org.eclipse.debug.internal.ui.DebugUIPlugin$8.run(DebugUIPlugin.java:1256)
      at org.eclipse.core.internal.jobs.Worker.run(Worker.java:56)
  </code></pre>