STS4 Java Editor Delays - Classpath Notifications

STS4 Version: 4.1.2.RELEASE Build Id: 201902210640 Eclipse Platform 4.10.0.v20181206-0815 Eclipse Java Development Tools 3.16.0.v20181206-1038

When I edit a .java file, after a few seconds my entire STS environment freezes (including menu items, etc). A few seconds later it resumes, and whatever I typed/deleted appears in the editor. It makes the program basically unusable for Java editing.

I switched on UI Responsiveness Monitoring and can see that when the delay begins, the following data appears in the Error Log:

Plug-in: org.springframework.tooling.ls.eclipse.commons
- Preparing classpath changed notification some.project.name
- exists = true open = true => deleted = false
- classpath=236 entries
- executing callback sts4.classpath.ZwJNwQiO some.project.name false 236
- executing callback sts4.classpath.ZwJNwQiO FAILED

A stack trace is also present:

java.lang.UnsupportedOperationException: No language server has registered to handle command 'sts4.classpath.ZwJNwQiO'
	at org.springframework.tooling.ls.eclipse.commons.LSP4ECommandExecutor.executeClientCommand(LSP4ECommandExecutor.java:42)
	at org.springframework.tooling.jdt.ls.commons.classpath.ReusableClasspathListenerHandler$Subscriptions$2.run(ReusableClasspathListenerHandler.java:179)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

Session Data:

eclipse.buildId=4.1.2.201902210640-RELEASE
java.version=1.8.0_202
java.vendor=Amazon.com Inc.
BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=en_GB
Framework arguments:  -product org.springframework.boot.ide.branding.sts4
Command-line arguments:  -os win32 -ws win32 -arch x86_64 -product org.springframework.boot.ide.branding.sts4

There is also this stack trace, output to the Error Log when the UI responsiveness monitoring is triggered:

Stack Trace
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
    at java.util.concurrent.CompletableFuture$Signaller.block(CompletableFuture.java:1695)
    at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3323)
    at java.util.concurrent.CompletableFuture.timedGet(CompletableFuture.java:1775)
    at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1915)
    at org.eclipse.lsp4e.LanguageServerWrapper.stop(LanguageServerWrapper.java:350)
    at org.eclipse.lsp4e.LanguageServerWrapper.disconnect(LanguageServerWrapper.java:509)
    at org.eclipse.lsp4e.LanguageServerWrapper.stop(LanguageServerWrapper.java:363)
    at org.eclipse.lsp4e.LanguageServerWrapper.start(LanguageServerWrapper.java:184)
    at org.eclipse.lsp4e.LanguageServerWrapper.getInitializedServer(LanguageServerWrapper.java:562)
    at org.eclipse.lsp4e.DocumentContentSynchronizer.documentChanged(DocumentContentSynchronizer.java:89)
    at org.eclipse.jface.text.AbstractDocument.doFireDocumentChanged2(AbstractDocument.java:747)
    at org.eclipse.jface.text.AbstractDocument.doFireDocumentChanged(AbstractDocument.java:716)
    at org.eclipse.jface.text.AbstractDocument.doFireDocumentChanged(AbstractDocument.java:700)
    at org.eclipse.jface.text.AbstractDocument.fireDocumentChanged(AbstractDocument.java:774)
    at org.eclipse.jface.text.AbstractDocument.replace(AbstractDocument.java:1105)
    at org.eclipse.core.internal.filebuffers.SynchronizableDocument.replace(SynchronizableDocument.java:176)
    at org.eclipse.jface.text.AbstractDocument.replace(AbstractDocument.java:1123)
    at org.eclipse.core.internal.filebuffers.SynchronizableDocument.replace(SynchronizableDocument.java:164)
    at org.eclipse.jface.text.projection.ProjectionTextStore.replace(ProjectionTextStore.java:106)
    at org.eclipse.jface.text.AbstractDocument.replace(AbstractDocument.java:1098)
    at org.eclipse.jface.text.AbstractDocument.replace(AbstractDocument.java:1123)
    at org.eclipse.jface.text.projection.ProjectionDocument.replace(ProjectionDocument.java:628)
    at org.eclipse.jface.text.DefaultDocumentAdapter.replaceTextRange(DefaultDocumentAdapter.java:236)
    at org.eclipse.swt.custom.StyledText.modifyContent(StyledText.java:7390)
    at org.eclipse.swt.custom.StyledText.sendKeyEvent(StyledText.java:8254)
    at org.eclipse.swt.custom.StyledText.doContent(StyledText.java:2502)
    at org.eclipse.swt.custom.StyledText.handleKey(StyledText.java:6038)
    at org.eclipse.swt.custom.StyledText.handleKeyDown(StyledText.java:6069)
    at org.eclipse.swt.custom.StyledText.lambda$1(StyledText.java:5767)
    at org.eclipse.swt.custom.StyledText$$Lambda$329/1187280528.handleEvent(Unknown Source)
    at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:89)
    at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4131)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1055)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1079)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1064)
    at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1106)
    at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1102)
    at org.eclipse.swt.widgets.Widget.wmChar(Widget.java:1489)
    at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:4888)
    at org.eclipse.swt.widgets.Canvas.WM_CHAR(Canvas.java:353)
    at org.eclipse.swt.widgets.Control.windowProc(Control.java:4768)
    at org.eclipse.swt.widgets.Canvas.windowProc(Canvas.java:348)
    at org.eclipse.swt.widgets.Display.windowProc(Display.java:4770)
    at org.eclipse.swt.internal.win32.OS.DispatchMessage(Native Method)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3545)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1173)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1062)
    at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
    at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:636)
    at org.eclipse.ui.internal.Workbench$$Lambda$21/510207317.run(Unknown Source)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:563)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:151)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:155)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:137)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:107)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
    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:659)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:595)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1501)

At the point a .java file is opened (not edited) the following appears in the Console (with Spring Boot Language Server Console enabled):

09:09:44.134 [main] INFO  o.s.i.v.b.a.BootLanguagServerBootApp - Starting BootLanguagServerBootApp v1.4.0-SNAPSHOT on LT-13336 with PID 12552 (C:\cdl_install\sts-4.1.2.RELEASE\configuration\org.eclipse.osgi\620\data\1.4.0.201902210636-spring-boot-language-server-1.4.0-SNAPSHOT.jar started by NeilB in C:\cdl_install\sts-4.1.2.RELEASE)
09:09:44.136 [main] INFO  o.s.i.v.b.a.BootLanguagServerBootApp - No active profile set, falling back to default profiles: default
09:09:44.184 [main] INFO  o.s.c.a.AnnotationConfigApplicationContext - Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@71e7a66b: startup date [Fri Mar 15 09:09:44 GMT 2019]; root of context hierarchy
09:09:44.624 [main] INFO  o.s.b.f.a.AutowiredAnnotationBeanPostProcessor - JSR-330 'javax.inject.Inject' annotation found and supported for autowiring
09:09:45.227 [main] INFO  o.s.i.v.b.jdt.ls.JdtLsProjectCache - added listener - now listeners registered: 1
09:09:45.478 [main] INFO  o.s.i.v.b.j.utils.SpringSymbolIndex - project listener registered
09:09:45.706 [main] INFO  o.s.j.e.a.AnnotationMBeanExporter - Registering beans for JMX exposure on startup
09:09:45.719 [main] INFO  o.s.i.v.b.a.BootLanguagServerBootApp - Started BootLanguagServerBootApp in 2.663 seconds (JVM running for 3.625)
09:09:45.722 [LanguageServerApp-lifecycle] INFO  o.s.i.v.c.l.LanguageServerRunner - Server ready to start after 3628 ms
09:09:45.724 [LanguageServerApp-lifecycle] INFO  o.s.ide.vscode.commons.util.Log - Starting LS
09:09:45.724 [LanguageServerApp-lifecycle] INFO  o.s.ide.vscode.commons.util.Log - Connected to parent using stdio
09:09:45.785 [pool-3-thread-1] INFO  o.s.i.v.c.l.u.SimpleLanguageServer - Initializing
09:09:45.811 [pool-3-thread-1] INFO  o.s.i.v.c.l.u.SimpleLanguageServer - Returning server capabilities to client: ServerCapabilities [
  textDocumentSync = Either [
    left = Incremental
    right = null
  ]
  hoverProvider = true
  completionProvider = CompletionOptions [
    resolveProvider = true
    triggerCharacters = RegularImmutableList (
      "a",
      "b",
      "c",
      "d",
      "e",
      "f",
      "g",
      "h",
      "i",
      "j",
      "k",
      "l",
      "m",
      "n",
      "o",
      "p",
      "q",
      "r",
      "s",
      "t",
      "u",
      "v",
      "w",
      "x",
      "y",
      "z",
      "A",
      "B",
      "C",
      "D",
      "E",
      "F",
      "G",
      "H",
      "I",
      "J",
      "K",
      "L",
      "M",
      "N",
      "O",
      "P",
      "Q",
      "R",
      "S",
      "T",
      "U",
      "V",
      "W",
      "X",
      "Y",
      "Z",
      "."
    )
  ]
  signatureHelpProvider = null
  definitionProvider = true
  typeDefinitionProvider = null
  implementationProvider = null
  referencesProvider = true
  documentHighlightProvider = true
  documentSymbolProvider = true
  workspaceSymbolProvider = true
  codeActionProvider = Either [
    left = true
    right = null
  ]
  codeLensProvider = CodeLensOptions [
    resolveProvider = false
  ]
  documentFormattingProvider = null
  documentRangeFormattingProvider = null
  documentOnTypeFormattingProvider = null
  renameProvider = null
  documentLinkProvider = null
  colorProvider = null
  foldingRangeProvider = null
  executeCommandProvider = ExecuteCommandOptions [
    commands = SingletonImmutableList (
      "sts.vscode-spring-boot.codeAction"
    )
  ]
  workspace = WorkspaceServerCapabilities [
    workspaceFolders = WorkspaceFoldersOptions [
      supported = true
      changeNotifications = Either [
        left = 7720d750-54a3-477c-a2c7-596d631e65f8
        right = null
      ]
    ]
  ]
  semanticHighlighting = null
  experimental = null
]
09:09:45.854 [Simple-Language-Server main thread] INFO  o.s.i.v.c.l.u.SimpleLanguageServer - Initialization completed after 3760 ms
09:09:46.315 [Simple-Language-Server main thread] INFO  o.s.i.v.b.jdt.ls.JdtLsProjectCache - Project Created: file:/C:/sts-workspace/some.project.name
09:09:46.362 [Simple-Language-Server main thread] INFO  o.s.i.v.b.jdt.ls.JdtLsProjectCache - Classpath has 212 entries 186 source attachements
09:09:46.362 [Simple-Language-Server main thread] INFO  o.s.i.v.b.jdt.ls.JdtLsProjectCache - listeners registered: 1
09:09:46.362 [Simple-Language-Server main thread] INFO  o.s.i.v.b.j.l.JavaProjectsServiceWithFallback - Project created: file:/C:/sts-workspace/some.project.name
09:09:46.363 [Simple-Language-Server main thread] INFO  o.s.i.v.b.j.utils.SpringSymbolIndex - project created event: some.project.name
09:09:46.769 [Simple-Language-Server main thread] INFO  o.s.i.v.b.j.u.SpringLiveHoverWatchdog - project created event: some.project.name
09:09:46.774 [Simple-Language-Server main thread] INFO  o.s.i.v.b.a.BootLanguageServerInitializer - A project changed some.project.name, triggering reconcile on all open documents
09:09:46.999 [Simple-Language-Server main thread] INFO  o.s.i.v.b.jdt.ls.JdtLsProjectCache - Project Created: file:/C:/sts-workspace/hummingbird.rules.demo
09:09:47.090 [Simple-Language-Server main thread] INFO  o.s.i.v.b.jdt.ls.JdtLsProjectCache - Classpath has 238 entries 211 source attachements
09:09:47.090 [Simple-Language-Server main thread] INFO  o.s.i.v.b.jdt.ls.JdtLsProjectCache - listeners registered: 1
09:09:47.090 [Simple-Language-Server main thread] INFO  o.s.i.v.b.j.l.JavaProjectsServiceWithFallback - Project created: file:/C:/sts-workspace/some.different.project
09:09:47.090 [Simple-Language-Server main thread] INFO  o.s.i.v.b.j.utils.SpringSymbolIndex - project created event: some.different.project
==== Process Terminated====

Note that it mentions two different project names even though the java file belongs in some.project.name only (although a file in some.different.project is open in STS at the same time).

In STS3 the same files allow me to edit without issue.

Thanks, Neil

[slavap]

@martinlippert I’ve updated to 4.2.1 today and “Ctrl+Click on any java class/method” problem is resolved for me.

[martinlippert]

@mweirauch Agree, looks indeed not related to anything Spring Tools specific, you should report that to bugs.eclipse.org for sure.

In case you would like to take a look at the log file and search for items, you could also open that file using a random editor of your choice, it should be located at: <workspace>/.metadata/.log.