sts4: java.util.concurrent.TimeoutException after sometime of usage when using content assist

Hi,

sometimes after some usage of the Eclipse Spring Tools version, I’m getting UI freezes when trying to use content-assist (Ctrl+Space). There is also a stacktrace in my journalctl -f [1].

I’m not sure why it happens though. I always just use the IDE as normal and after some time of usage without problems, I’m getting this problem. A restart of the IDE fixes the problem.

Specs:

• Fedora 29
• Java 11 (not sure if this could be the cause, I will try Java 8 for some time and then report back here)
• Eclipse STS Version: 4.0.1.RELEASE
• No plugins installed

I’m happy to provide additional info if needed.

[1]:

Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at java.util.concurrent.CompletableFuture.timedGet(CompletableFuture.java:1771)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1915)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.springframework.tooling.boot.ls.jdt.SpringBootJavaCompletionProposalComputer.computeCompletionProposals(SpringBootJavaCompletionProposalComputer.java:55)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jdt.internal.ui.text.java.CompletionProposalComputerDescriptor.computeCompletionProposals(CompletionProposalComputerDescriptor.java:336)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jdt.internal.ui.text.java.CompletionProposalCategory.computeCompletionProposals(CompletionProposalCategory.java:340)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.collectProposals(ContentAssistProcessor.java:334)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.computeCompletionProposals(ContentAssistProcessor.java:291)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.text.contentassist.ContentAssistant$2.lambda$0(ContentAssistant.java:2012)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at java.util.Collections$SingletonSet.forEach(Collections.java:4767)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.text.contentassist.ContentAssistant$2.run(ContentAssistant.java:2011)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.text.contentassist.ContentAssistant.computeCompletionProposals(ContentAssistant.java:2008)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.text.contentassist.CompletionProposalPopup.computeProposals(CompletionProposalPopup.java:561)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.text.contentassist.CompletionProposalPopup.lambda$0(CompletionProposalPopup.java:491)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:72)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.text.contentassist.CompletionProposalPopup.showProposals(CompletionProposalPopup.java:486)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.text.contentassist.ContentAssistant.showPossibleCompletions(ContentAssistant.java:1822)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitEditor$AdaptedSourceViewer.doOperation(CompilationUnitEditor.java:189)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.ui.texteditor.ContentAssistAction.lambda$0(ContentAssistAction.java:85)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:72)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.ui.texteditor.ContentAssistAction.run(ContentAssistAction.java:84)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.action.Action.runWithEvent(Action.java:476)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.jface.commands.ActionHandler.execute(ActionHandler.java:121)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:96)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at sun.reflect.GeneratedMethodAccessor72.invoke(Unknown Source)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at java.lang.reflect.Method.invoke(Method.java:498)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:58)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:320)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:254)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:164)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:156)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.commands.Command.executeWithChecks(Command.java:497)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:490)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:207)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.executeCommand(KeyBindingDispatcher.java:308)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.press(KeyBindingDispatcher.java:582)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.processKeyEvent(KeyBindingDispatcher.java:651)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.filterKeySequenceBindings(KeyBindingDispatcher.java:441)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.access$2(KeyBindingDispatcher.java:384)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher$KeyDownFilter.handleEvent(KeyBindingDispatcher.java:96)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:89)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Display.filterEvent(Display.java:1752)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1373)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1400)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1383)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1412)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Widget.gtk_key_press_event(Widget.java:787)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Control.gtk_key_press_event(Control.java:3794)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Composite.gtk_key_press_event(Composite.java:862)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Widget.windowProc(Widget.java:1990)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Control.windowProc(Control.java:6524)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Display.windowProc(Display.java:6014)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.internal.gtk.GTK._gtk_main_do_event(Native Method)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.internal.gtk.GTK.gtk_main_do_event(GTK.java:4118)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Display.eventProc(Display.java:1414)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.internal.gtk.OS._g_main_context_iteration(Native Method)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.internal.gtk.OS.g_main_context_iteration(OS.java:1596)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:4581)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1173)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1062)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:628)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:563)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:151)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:155)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:199)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:137)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:107)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:391)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:246)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at java.lang.reflect.Method.invoke(Method.java:498)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:659)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.equinox.launcher.Main.basicRun(Main.java:595)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.equinox.launcher.Main.run(Main.java:1501)
Nov 10 15:56:54 localhost.localdomain Spring Tool Suite 4.desktop[1878]:         at org.eclipse.equinox.launcher.Main.main(Main.java:1474)