Searched on Google with the first line of a JAVA stack trace?

We can recommend more relevant solutions and speed up debugging when you paste your entire stack trace with the exception message. Try a sample exception.

Recommended solutions based on your search

java.util.ConcurrentModificationException: null at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:966) at java.util.LinkedList$ListItr.next(LinkedList.java:888) at com.vaadin.navigator.Navigator.fireAfterViewChange(Navigator.java:650) at com.vaadin.navigator.Navigator.navigateTo(Navigator.java:580) at com.vaadin.navigator.Navigator.navigateTo(Navigator.java:526) at de.oio.ui.MainUI.beforeViewChange(MainUI.java:34) at com.vaadin.navigator.Navigator.fireBeforeViewChange(Navigator.java:601) at com.vaadin.navigator.Navigator.navigateTo(Navigator.java:553) at com.vaadin.navigator.Navigator.navigateTo(Navigator.java:526) at com.vaadin.navigator.Navigator$UriFragmentManager.uriFragmentChanged(Navigator.java:140)