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

Solutions on the web

via jabref by fhiguera
, 2 years ago
This exception has no message.
via sourceforge.net by Unknown author, 2 years ago
java.lang.NullPointerException: 	at net.sf.jabref.groups.GroupTreeNode.hashCode(GroupTreeNode.java:383)	at javax.swing.tree.TreePath.hashCode(Unknown Source)	at java.util.Hashtable.hash(Unknown Source)	at java.util.Hashtable.put(Unknown Source)	at javax.swing.tree.VariableHeightLayoutCache.addMapping(Unknown Source)	at javax.swing.tree.VariableHeightLayoutCache.access$000(Unknown Source)	at javax.swing.tree.VariableHeightLayoutCache$TreeStateNode.setParent(Unknown Source)	at javax.swing.tree.DefaultMutableTreeNode.insert(Unknown Source)	at javax.swing.tree.DefaultMutableTreeNode.add(Unknown Source)	at javax.swing.tree.VariableHeightLayoutCache$TreeStateNode.expand(Unknown Source)	at javax.swing.tree.VariableHeightLayoutCache$TreeStateNode.expand(Unknown Source)	at javax.swing.tree.VariableHeightLayoutCache.ensurePathIsExpanded(Unknown Source)	at javax.swing.tree.VariableHeightLayoutCache.setExpandedState(Unknown Source)	at javax.swing.plaf.basic.BasicTreeUI.updateExpandedDescendants(Unknown Source)	at javax.swing.plaf.basic.BasicTreeUI$Handler.treeExpanded(Unknown Source)	at javax.swing.JTree.fireTreeExpanded(Unknown Source)	at javax.swing.JTree.setExpandedState(Unknown Source)	at javax.swing.JTree.expandPath(Unknown Source)	at net.sf.jabref.groups.GroupSelector.revalidateGroups(GroupSelector.java:838)	at net.sf.jabref.groups.GroupSelector.revalidateGroups(GroupSelector.java:860)	at net.sf.jabref.groups.GroupSelector.revalidateGroups(GroupSelector.java:851)	at net.sf.jabref.PrefsDialog3$OkAction$1.update(PrefsDialog3.java:253)	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)	at java.lang.reflect.Method.invoke(Unknown Source)	at spin.Invocation.evaluate(Invocation.java:175)	at spin.over.SpinOverEvaluator.evaluate(SpinOverEvaluator.java:62)	at spin.ProxyFactory.evaluteInvocation(ProxyFactory.java:85)	at spin.JDKProxyFactory$SpinInvocationHandler.invoke(JDKProxyFactory.java:102)	at com.sun.proxy.$Proxy0.update(Unknown Source)	at net.sf.jabref.PrefsDialog3$OkAction.actionPerformed(PrefsDialog3.java:259)	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)	at java.awt.Component.processMouseEvent(Unknown Source)	at javax.swing.JComponent.processMouseEvent(Unknown Source)	at java.awt.Component.processEvent(Unknown Source)	at java.awt.Container.processEvent(Unknown Source)	at java.awt.Component.dispatchEventImpl(Unknown Source)	at java.awt.Container.dispatchEventImpl(Unknown Source)	at java.awt.Component.dispatchEvent(Unknown Source)	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)	at java.awt.Container.dispatchEventImpl(Unknown Source)	at java.awt.Window.dispatchEventImpl(Unknown Source)	at java.awt.Component.dispatchEvent(Unknown Source)	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)	at java.awt.EventQueue.access$200(Unknown Source)	at java.awt.EventQueue$3.run(Unknown Source)	at java.awt.EventQueue$3.run(Unknown Source)	at java.security.AccessController.doPrivileged(Native Method)	at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)	at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)	at java.awt.EventQueue$4.run(Unknown Source)	at java.awt.EventQueue$4.run(Unknown Source)	at java.security.AccessController.doPrivileged(Native Method)	at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)	at java.awt.EventQueue.dispatchEvent(Unknown Source)	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)	at java.awt.EventDispatchThread.run(Unknown Source)