Invalid input URL error in Eclipse - eclipse

Question

During setup of my project in eclipse, I have facing this error in error logs:
java.io.IOException: Unable to resolve plug-in "platform:/plugin/org.jboss.tools.seam.ui/icons/seam16.png".
at org.eclipse.core.internal.runtime.PlatformURLPluginConnection.parse(PlatformURLPluginConnection.java:61)
at org.eclipse.core.internal.runtime.FindSupport.find(FindSupport.java:290)
at org.eclipse.core.runtime.FileLocator.find(FileLocator.java:152)
at org.eclipse.jface.resource.URLImageDescriptor.getStream(URLImageDescriptor.java:152)
at org.eclipse.jface.resource.URLImageDescriptor.getImageData(URLImageDescriptor.java:120)
at org.eclipse.jface.resource.URLImageDescriptor.access$3(URLImageDescriptor.java:118)
at org.eclipse.jface.resource.URLImageDescriptor$URLImageDataProvider.getImageData(URLImageDescriptor.java:74)
at org.eclipse.swt.internal.DPIUtil.validateAndGetImageDataAtZoom(DPIUtil.java:393)
at org.eclipse.swt.graphics.Image.<init>(Image.java:731)
at org.eclipse.jface.resource.URLImageDescriptor.createImage(URLImageDescriptor.java:271)
at org.eclipse.jface.resource.ImageDescriptor.createImage(ImageDescriptor.java:240)
at org.eclipse.jface.resource.ImageDescriptor.createImage(ImageDescriptor.java:218)
at org.eclipse.ui.internal.dialogs.ViewLabelProvider.getImage(ViewLabelProvider.java:93)
at org.eclipse.jface.viewers.ColumnLabelProvider.update(ColumnLabelProvider.java:35)
at org.eclipse.jface.viewers.ViewerColumn.refresh(ViewerColumn.java:141)
at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:946)
at org.eclipse.jface.viewers.AbstractTreeViewer$UpdateItemSafeRunnable.run(AbstractTreeViewer.java:117)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.ui.internal.JFaceUtil.lambda$0(JFaceUtil.java:44)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:173)
at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:1025)
at org.eclipse.jface.viewers.StructuredViewer$UpdateItemSafeRunnable.run(StructuredViewer.java:475)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.ui.internal.JFaceUtil.lambda$0(JFaceUtil.java:44)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:173)
at org.eclipse.jface.viewers.StructuredViewer.updateItem(StructuredViewer.java:2159)
at org.eclipse.jface.viewers.AbstractTreeViewer.createTreeItem(AbstractTreeViewer.java:840)
at org.eclipse.jface.viewers.AbstractTreeViewer.lambda$0(AbstractTreeViewer.java:817)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.eclipse.jface.viewers.AbstractTreeViewer.createChildren(AbstractTreeViewer.java:792)
at org.eclipse.jface.viewers.TreeViewer.createChildren(TreeViewer.java:595)
at org.eclipse.jface.viewers.AbstractTreeViewer.createChildren(AbstractTreeViewer.java:763)
at org.eclipse.jface.viewers.AbstractTreeViewer.setExpandedState(AbstractTreeViewer.java:2459)
at org.eclipse.ui.dialogs.FilteredTree$1.recursiveExpand(FilteredTree.java:586)
at org.eclipse.ui.dialogs.FilteredTree$1.runInUIThread(FilteredTree.java:529)
at org.eclipse.ui.progress.UIJob.lambda$0(UIJob.java:95)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:37)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:182)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4213)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3820)
at org.eclipse.jface.window.Window.runEventLoop(Window.java:818)
at org.eclipse.jface.window.Window.open(Window.java:794)
at org.eclipse.ui.handlers.ShowViewHandler.openOther(ShowViewHandler.java:102)
at org.eclipse.ui.handlers.ShowViewHandler.execute(ShowViewHandler.java:77)
at org.eclipse.ui.internal.handlers.HandlerProxy.execute(HandlerProxy.java:291)
at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:92)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:55)
at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:305)
at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:239)
at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:132)
at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:152)
at org.eclipse.core.commands.Command.executeWithChecks(Command.java:494)
at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:487)
at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:210)
at org.eclipse.ui.internal.handlers.LegacyHandlerService.executeCommand(LegacyHandlerService.java:390)
at org.eclipse.ui.internal.ShowViewMenu$1.run(ShowViewMenu.java:139)
at org.eclipse.jface.action.Action.runWithEvent(Action.java:473)
at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:565)
at org.eclipse.jface.action.ActionContributionItem.lambda$4(ActionContributionItem.java:397)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:86)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4428)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1079)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4238)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3817)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1150)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1039)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:153)
at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:680)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:594)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:388)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:653)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:590)
at org.eclipse.equinox.launcher.Main.run(Main.java:1499)
at org.eclipse.equinox.launcher.Main.main(Main.java:1472)

Answer 1

The missing seam16.png probably no longer exists in the updated or uninstalled org.jboss.tools.seam.ui plug-in but is still used in the user interface which is persisted.
In this case, switching to a new workspace (File > Switch Workspace) or resting the perspective (Window > Perspective > Reset Perspective...) should fix the error.
If other or newer errors occur, this has nothing to do with the missing PNG but might be caused by the same update. You can revert an update: in Help > About Eclipse click on the Installation Details button and see Installation History tab. But before that, a Help > Check for Updates would be worth a try.