title: After migrating from free Vaadin 7 to Vaadin 8, licence is required?
body: <p>I am migrating a Java 7 project that makes use of Vaadin 7 to Java 11 and Vaadin 8.</p>
  <p>With Java 7/Vaadin 7 the project was using the following Vaadin libs:
  <a href="https://i.stack.imgur.com/UL5YD.png" rel="nofollow noreferrer">Vaddin7 modules</a></p>
  <p>For the migration we followed the guide described here: <a href="https://vaadin.com/docs/v8/framework/migration/migrating-to-vaadin8" rel="nofollow noreferrer">https://vaadin.com/docs/v8/framework/migration/migrating-to-vaadin8</a>
  However, after deploying I had the surprise that Vaadin is asking for license as I can understand
  from this exception</p>
  <pre><code>Caused by: java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11.XToolkit
          at java.base/java.lang.Class.forName0(Native Method)
          at java.base/java.lang.Class.forName(Class.java:315)
          at java.desktop/java.awt.Toolkit$2.run(Toolkit.java:588)
          at java.desktop/java.awt.Toolkit$2.run(Toolkit.java:583)
          at java.base/java.security.AccessController.doPrivileged(Native Method)
          at java.desktop/java.awt.Toolkit.getDefaultToolkit(Toolkit.java:582)
          at java.desktop/java.awt.Desktop.isDesktopSupported(Desktop.java:328)
          at java.desktop/java.awt.Desktop.getDesktop(Desktop.java:302)
          at com.vaadin.pro.licensechecker.SystemBrowser.open(SystemBrowser.java:27)
          at com.vaadin.pro.licensechecker.VaadinComIntegration.openBrowserAndWaitForKey(VaadinComIntegration.java:26)
          at com.vaadin.pro.licensechecker.LicenseChecker.checkLicense(LicenseChecker.java:56)
          at com.vaadin.pro.licensechecker.LicenseChecker.checkLicense(LicenseChecker.java:36)
          at com.vaadin.server.VaadinServletService.verifyLicense(VaadinServletService.java:67)
          at com.vaadin.server.VaadinServletService.&lt;init&gt;(VaadinServletService.java:49)
          at com.vaadin.spring.server.SpringVaadinServletService.&lt;init&gt;(SpringVaadinServletService.java:56)
          at com.vaadin.spring.server.SpringVaadinServlet.createServletService(SpringVaadinServlet.java:150)
          at com.vaadin.server.VaadinServlet.createServletService(VaadinServlet.java:396)
          at com.vaadin.server.VaadinServlet.init(VaadinServlet.java:226)
  </code></pre>
  <p>The project is not using any of the commercial add-ons, so I need further guidance on how to migrate to Vaadin 8 free edition.</p>