JDK-9 no me deja usar cadenas: "java.lang.String es ambiguo"?

Hace una semana, todos los proyectos que tenía funcionaban normalmente, pero cuando actualicé mi Eclipse a la versión Oxygen e instalé JDK-9, las cosas se volvieron extrañas. Cuando intento usar Strings, después de un tiempo (más bien cada vez que guardo el proyecto) el compilador me arroja un error por cada String en mi proyecto.

El tipo de cadena se reconoce como una clase ambigua



"El tipo java.lang.String es ambiguo"

Así que intenté importarjava.lang.String para ver si soluciona el error:

Después de la importación

"Se puede acceder al paquete java.lang desde más de un módulo: java.base, java.base"

¡Sorpresa!

No lo hace :(
Intenté buscar estos mensajes en Google y SO, pero no encontré nada ...
Sin embargo, el código que se ejecuta en JDK 8 parece ejecutarse normalmente, échale un vistazo:

Cambio a JDK 8 (1.8.0_72)

(El código no muestra ningún error antes de Aplicar porque lo he aplicado, y abre de nuevo las preferencias del compilador para la captura de pantalla)

El error de la consola:

Error: método principal no encontrado en claseme.mateusakino.ypul.yPuLTester, defina el método principal como:
public static void main(String[] args) o una clase de aplicación JavaFX debe extendersejavafx.application.Application

EDITAR 1 - Clase principal

EDITAR 5 - Stacktrace de los errores enEditar 4 (espacio de trabajo / .metadata / .log)
!SESSION 2017-10-13 13:11:39.551 -----------------------------------------------
eclipse.buildId=4.7.1.M20171009-0410
java.version=9
java.vendor=Oracle Corporation
BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=en_US
Framework arguments:  -product org.eclipse.epp.package.java.product
Command-line arguments:  -os win32 -ws win32 -arch x86_64 -product org.eclipse.epp.package.java.product

This is a continuation of log file C:\Users\Home\Desktop\Developer Folders\Java\Oxygen Workspace\.metadata\.bak_0.log
Created Time: 2017-10-13 13:43:14.245

!ENTRY org.eclipse.core.resources 4 75 2017-10-13 13:43:14.245
!MESSAGE Errors occurred during the build.
!SUBENTRY 1 org.eclipse.jdt.core 4 75 2017-10-13 13:43:14.245
!MESSAGE Errors running builder 'Java Builder' on project 'yPuL'.
!STACK 0
java.lang.NullPointerException
    at org.eclipse.jdt.internal.compiler.lookup.ModuleBinding$UnNamedModule.canAccess(ModuleBinding.java:71)
    at org.eclipse.jdt.internal.compiler.lookup.PackageBinding.getTypeOrPackage(PackageBinding.java:230)
    at org.eclipse.jdt.internal.compiler.lookup.Scope.getPackage(Scope.java:2922)
    at org.eclipse.jdt.internal.compiler.ast.QualifiedTypeReference.getTypeBinding(QualifiedTypeReference.java:108)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.getTypeBinding(ArrayQualifiedTypeReference.java:93)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.internalResolveType(TypeReference.java:495)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.internalResolveType(ArrayQualifiedTypeReference.java:107)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:586)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:582)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesWithSuspendedTempErrorHandlingPolicy(SourceTypeBinding.java:1932)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesFor(SourceTypeBinding.java:1835)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.methods(SourceTypeBinding.java:1525)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.internalFaultInTypeForFieldsAndMethods(SourceTypeBinding.java:907)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.faultInTypesForFieldsAndMethods(SourceTypeBinding.java:902)
    at org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope.faultInTypes(CompilationUnitScope.java:514)
    at org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:882)
    at org.eclipse.jdt.internal.compiler.ProcessTaskManager.run(ProcessTaskManager.java:141)
    at java.base/java.lang.Thread.run(Thread.java:844)

!ENTRY org.eclipse.core.resources 4 2 2017-10-13 13:43:24.691
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.core.resources".
!STACK 0
java.lang.NullPointerException

!ENTRY org.eclipse.core.resources 4 75 2017-10-13 13:43:24.695
!MESSAGE Errors occurred during the build.
!SUBENTRY 1 org.eclipse.jdt.core 4 75 2017-10-13 13:43:24.695
!MESSAGE Errors running builder 'Java Builder' on project 'yPuL'.
!STACK 0
java.lang.NullPointerException

!ENTRY org.eclipse.core.resources 4 2 2017-10-13 13:43:39.104
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.core.resources".
!STACK 0
java.lang.NullPointerException

!ENTRY org.eclipse.core.resources 4 75 2017-10-13 13:43:39.110
!MESSAGE Errors occurred during the build.
!SUBENTRY 1 org.eclipse.jdt.core 4 75 2017-10-13 13:43:39.110
!MESSAGE Errors running builder 'Java Builder' on project 'yPuL'.
!STACK 0
java.lang.NullPointerException

!ENTRY org.eclipse.core.resources 4 2 2017-10-13 13:44:37.810
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.core.resources".
!STACK 0
java.lang.NullPointerException
    at org.eclipse.jdt.internal.compiler.lookup.ModuleBinding$UnNamedModule.canAccess(ModuleBinding.java:71)
    at org.eclipse.jdt.internal.compiler.lookup.PackageBinding.getTypeOrPackage(PackageBinding.java:230)
    at org.eclipse.jdt.internal.compiler.lookup.Scope.getPackage(Scope.java:2922)
    at org.eclipse.jdt.internal.compiler.ast.QualifiedTypeReference.getTypeBinding(QualifiedTypeReference.java:108)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.getTypeBinding(ArrayQualifiedTypeReference.java:93)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.internalResolveType(TypeReference.java:495)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.internalResolveType(ArrayQualifiedTypeReference.java:107)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:586)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:582)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesWithSuspendedTempErrorHandlingPolicy(SourceTypeBinding.java:1932)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesFor(SourceTypeBinding.java:1835)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.methods(SourceTypeBinding.java:1525)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.internalFaultInTypeForFieldsAndMethods(SourceTypeBinding.java:907)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.faultInTypesForFieldsAndMethods(SourceTypeBinding.java:902)
    at org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope.faultInTypes(CompilationUnitScope.java:514)
    at org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:882)
    at org.eclipse.jdt.internal.compiler.ProcessTaskManager.run(ProcessTaskManager.java:141)
    at java.base/java.lang.Thread.run(Thread.java:844)

!ENTRY org.eclipse.core.resources 4 75 2017-10-13 13:44:37.814
!MESSAGE Errors occurred during the build.
!SUBENTRY 1 org.eclipse.jdt.core 4 75 2017-10-13 13:44:37.814
!MESSAGE Errors running builder 'Java Builder' on project 'yPuL'.
!STACK 0
java.lang.NullPointerException
    at org.eclipse.jdt.internal.compiler.lookup.ModuleBinding$UnNamedModule.canAccess(ModuleBinding.java:71)
    at org.eclipse.jdt.internal.compiler.lookup.PackageBinding.getTypeOrPackage(PackageBinding.java:230)
    at org.eclipse.jdt.internal.compiler.lookup.Scope.getPackage(Scope.java:2922)
    at org.eclipse.jdt.internal.compiler.ast.QualifiedTypeReference.getTypeBinding(QualifiedTypeReference.java:108)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.getTypeBinding(ArrayQualifiedTypeReference.java:93)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.internalResolveType(TypeReference.java:495)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.internalResolveType(ArrayQualifiedTypeReference.java:107)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:586)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:582)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesWithSuspendedTempErrorHandlingPolicy(SourceTypeBinding.java:1932)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesFor(SourceTypeBinding.java:1835)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.methods(SourceTypeBinding.java:1525)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.internalFaultInTypeForFieldsAndMethods(SourceTypeBinding.java:907)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.faultInTypesForFieldsAndMethods(SourceTypeBinding.java:902)
    at org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope.faultInTypes(CompilationUnitScope.java:514)
    at org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:882)
    at org.eclipse.jdt.internal.compiler.ProcessTaskManager.run(ProcessTaskManager.java:141)
    at java.base/java.lang.Thread.run(Thread.java:844)

!ENTRY org.eclipse.core.resources 4 2 2017-10-13 13:44:53.701
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.core.resources".
!STACK 0
java.lang.NullPointerException
    at org.eclipse.jdt.internal.compiler.lookup.ModuleBinding$UnNamedModule.canAccess(ModuleBinding.java:71)
    at org.eclipse.jdt.internal.compiler.lookup.PackageBinding.getTypeOrPackage(PackageBinding.java:230)
    at org.eclipse.jdt.internal.compiler.lookup.Scope.getPackage(Scope.java:2922)
    at org.eclipse.jdt.internal.compiler.ast.QualifiedTypeReference.getTypeBinding(QualifiedTypeReference.java:108)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.getTypeBinding(ArrayQualifiedTypeReference.java:93)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.internalResolveType(TypeReference.java:495)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.internalResolveType(ArrayQualifiedTypeReference.java:107)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:586)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:582)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesWithSuspendedTempErrorHandlingPolicy(SourceTypeBinding.java:1932)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesFor(SourceTypeBinding.java:1835)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.methods(SourceTypeBinding.java:1525)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.internalFaultInTypeForFieldsAndMethods(SourceTypeBinding.java:907)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.faultInTypesForFieldsAndMethods(SourceTypeBinding.java:902)
    at org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope.faultInTypes(CompilationUnitScope.java:514)
    at org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:882)
    at org.eclipse.jdt.internal.compiler.ProcessTaskManager.run(ProcessTaskManager.java:141)
    at java.base/java.lang.Thread.run(Thread.java:844)

!ENTRY org.eclipse.core.resources 4 75 2017-10-13 13:44:53.706
!MESSAGE Errors occurred during the build.
!SUBENTRY 1 org.eclipse.jdt.core 4 75 2017-10-13 13:44:53.706
!MESSAGE Errors running builder 'Java Builder' on project 'yPuL'.
!STACK 0
java.lang.NullPointerException
    at org.eclipse.jdt.internal.compiler.lookup.ModuleBinding$UnNamedModule.canAccess(ModuleBinding.java:71)
    at org.eclipse.jdt.internal.compiler.lookup.PackageBinding.getTypeOrPackage(PackageBinding.java:230)
    at org.eclipse.jdt.internal.compiler.lookup.Scope.getPackage(Scope.java:2922)
    at org.eclipse.jdt.internal.compiler.ast.QualifiedTypeReference.getTypeBinding(QualifiedTypeReference.java:108)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.getTypeBinding(ArrayQualifiedTypeReference.java:93)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.internalResolveType(TypeReference.java:495)
    at org.eclipse.jdt.internal.compiler.ast.ArrayQualifiedTypeReference.internalResolveType(ArrayQualifiedTypeReference.java:107)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:586)
    at org.eclipse.jdt.internal.compiler.ast.TypeReference.resolveType(TypeReference.java:582)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesWithSuspendedTempErrorHandlingPolicy(SourceTypeBinding.java:1932)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesFor(SourceTypeBinding.java:1835)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.methods(SourceTypeBinding.java:1525)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.internalFaultInTypeForFieldsAndMethods(SourceTypeBinding.java:907)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.faultInTypesForFieldsAndMethods(SourceTypeBinding.java:902)
    at org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope.faultInTypes(CompilationUnitScope.java:514)
    at org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:882)
    at org.eclipse.jdt.internal.compiler.ProcessTaskManager.run(ProcessTaskManager.java:141)
    at java.base/java.lang.Thread.run(Thread.java:844)
!SESSION 2017-10-13 13:46:42.392 -----------------------------------------------
eclipse.buildId=4.7.1.M20171009-0410
java.version=9
java.vendor=Oracle Corporation
BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=en_US
Framework arguments:  -product org.eclipse.epp.package.java.product
Command-line arguments:  -os win32 -ws win32 -arch x86_64 -product org.eclipse.epp.package.java.product

!ENTRY org.eclipse.jface 2 0 2017-10-13 13:46:49.852
!MESSAGE Keybinding conflicts occurred.  They may interfere with normal accelerator operation.
!SUBENTRY 1 org.eclipse.jface 2 0 2017-10-13 13:46:49.852
!MESSAGE A conflict occurred for CTRL+TAB:
Binding(CTRL+TAB,
    ParameterizedCommand(Command(org.eclipse.ui.window.nextEditor,Next Editor,
        Switch to the next editor,
        Category(org.eclipse.ui.category.window,Window,null,true),
        org.eclipse.ui.internal.WorkbenchHandlerServiceHandler@5e8359da,
        ,,true),null),
    org.eclipse.ui.defaultAcceleratorConfiguration,
    org.eclipse.ui.contexts.window,,,system)
Binding(CTRL+TAB,
    ParameterizedCommand(Command(org.eclipse.ui.window.nextEditor,Next Editor,
        Switch to the next editor,
        Category(org.eclipse.ui.category.window,Window,null,true),
        org.eclipse.ui.internal.WorkbenchHandlerServiceHandler@5e8359da,
        ,,true),null),
    org.eclipse.ui.defaultAcceleratorConfiguration,
    org.eclipse.ui.contexts.window,,,system)
!SUBENTRY 1 org.eclipse.jface 2 0 2017-10-13 13:46:49.852
!MESSAGE A conflict occurred for CTRL+SHIFT+TAB:
Binding(CTRL+SHIFT+TAB,
    ParameterizedCommand(Command(org.eclipse.ui.window.previousEditor,Previous Editor,
        Switch to the previous editor,
        Category(org.eclipse.ui.category.window,Window,null,true),
        org.eclipse.ui.internal.WorkbenchHandlerServiceHandler@36b6802f,
        ,,true),null),
    org.eclipse.ui.defaultAcceleratorConfiguration,
    org.eclipse.ui.contexts.window,,,system)
Binding(CTRL+SHIFT+TAB,
    ParameterizedCommand(Command(org.eclipse.ui.window.previousEditor,Previous Editor,
        Switch to the previous editor,
        Category(org.eclipse.ui.category.window,Window,null,true),
        org.eclipse.ui.internal.WorkbenchHandlerServiceHandler@36b6802f,
        ,,true),null),
    org.eclipse.ui.defaultAcceleratorConfiguration,
    org.eclipse.ui.contexts.window,,,system)

!ENTRY com.vaadin.designer2 1 0 2017-10-13 13:47:00.882
!MESSAGE Schedule fetching all notifications

!ENTRY com.vaadin.designer2 1 0 2017-10-13 13:47:02.845
!MESSAGE Parse notifications

!ENTRY com.vaadin.designer2 1 0 2017-10-13 13:47:03.278
!MESSAGE Requesting user info (notification settings URL)

!ENTRY com.vaadin.designer2 1 0 2017-10-13 13:47:04.704
!MESSAGE HTTP Response code :200

!ENTRY org.eclipse.egit.ui 2 0 2017-10-13 13:47:06.014
!MESSAGE Warning: The environment variable HOME is not set. The following directory will be used to store the Git
user global configuration and to define the default location to store repositories: 'C:\Users\Home'. If this is
not correct please set the HOME environment variable and restart Eclipse. Otherwise Git for Windows and
EGit might behave differently since they see different configuration options.
This warning can be switched off on the Team > Git > Confirmations and Warnings preference page.

!ENTRY org.eclipse.dltk.core 4 0 2017-10-13 13:47:07.129
!MESSAGE Unable to find any indexer

!ENTRY org.apache.ivyde.eclipse 1 0 2017-10-13 13:48:10.554
!MESSAGE starting IvyDE plugin

!ENTRY org.apache.ivyde.eclipse 1 0 2017-10-13 13:48:10.571
!MESSAGE IvyDE plugin started

!ENTRY org.eclipse.ui 2 2 2017-10-13 13:48:12.395
!MESSAGE Invalid property category path: org.eclipse.cdt.managedbuilder.ui.properties.Page_head_build (bundle: org.eclipse.cdt.ui, propertyPage: org.eclipse.cdt.managedbuilder.ui.properties.BuildLogPreferencePage)

!ENTRY org.eclipse.jface 4 2 2017-10-13 13:48:45.611
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.jface".
!STACK 0
java.lang.IllegalArgumentException
    at org.eclipse.core.resources.ProjectScope.<init>(ProjectScope.java:58)
    at com.vaadin.designer2.eclipse.preferences.VisualDesignerPreferences.getProjectPreferences(VisualDesignerPreferences.java:680)
    at com.vaadin.designer2.eclipse.preferences.VisualDesignerPreferences.getDefaultDesigner(VisualDesignerPreferences.java:245)
    at com.vaadin.designer2.eclipse.preferences.DesignerProjectPreferencePage.createDesignerSelection(DesignerProjectPreferencePage.java:179)
    at com.vaadin.designer2.eclipse.preferences.DesignerProjectPreferencePage.createContents(DesignerProjectPreferencePage.java:109)
    at org.eclipse.jface.preference.PreferencePage.createControl(PreferencePage.java:241)
    at org.eclipse.jface.preference.PreferenceDialog.createPageControl(PreferenceDialog.java:1426)
    at org.eclipse.jface.preference.PreferenceDialog$8.run(PreferenceDialog.java:1193)
    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.preference.PreferenceDialog.showPage(PreferenceDialog.java:1185)
    at org.eclipse.ui.internal.dialogs.FilteredPreferenceDialog.showPage(FilteredPreferenceDialog.java:591)
    at org.eclipse.jface.preference.PreferenceDialog$5.lambda$0(PreferenceDialog.java:657)
    at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
    at org.eclipse.jface.preference.PreferenceDialog$5.selectionChanged(PreferenceDialog.java:654)
    at org.eclipse.jface.viewers.StructuredViewer$3.run(StructuredViewer.java:872)
    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.firePostSelectionChanged(StructuredViewer.java:869)
    at org.eclipse.jface.viewers.StructuredViewer.handlePostSelect(StructuredViewer.java:1238)
    at org.eclipse.jface.viewers.StructuredViewer.lambda$0(StructuredViewer.java:1261)
    at org.eclipse.swt.events.SelectionListener$1.widgetSelected(SelectionListener.java:81)
    at org.eclipse.jface.util.OpenStrategy.firePostSelectionEvent(OpenStrategy.java:261)
    at org.eclipse.jface.util.OpenStrategy.access$5(OpenStrategy.java:256)
    at org.eclipse.jface.util.OpenStrategy$1.lambda$1(OpenStrategy.java:426)
    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.dialogs.PropertyDialogAction.run(PropertyDialogAction.java:157)
    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 java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:564)
    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)
EDITAR 7:

yo podríareproducir en otro espacio de trabajo (Temp Workspace), y aquí está el.classpath archivo solicitado de @howlger:

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
    <classpathentry kind="src" path="src"/>
    <classpathentry kind="output" path="bin"/>
</classpath>
EDITAR 8 - Informe Eclipse (Preguntado porAullador):

https://bugs.eclipse.org/bugs/show_bug.cgi?id=526020

Detalles:SO: Windows 10 Home (64 bits)JDK 9.0Eclipse inicial: lanzamiento de oxígeno (4.7.0) ID de compilación: 20170620-1800Current Eclipse: Oxygen.1a Release (4.7.1a) ID de compilación: 20171005-1200EDITAR 4: Configuración del proyecto:Bibliotecas referenciadas:jRegexCodificación: UTF-8Configuraciones del compiladorEnvieroments de ejecuciónEDITAR 4: Versión de Java 9: compilación 9 + 181EDITAR 4: Java VM de servidor de 64 bits HotSpot (TM) (compilación 9 + 181, modo mixto)EDITAR 6: Todos los complementos de EclipseSi se necesita cualquier otra información, pregunte en la sección de comentarios ...Lo que probé:Reiniciando el IDEBuscar si hay más de una cadena en las propuestas / finalización de Java (solo había una,java.lang's).Comprueba la biblioteca del sistema JRE para más de unojava.base paquete (solo había uno, dejrt-fs.jar)EDITAR 2: agregar módulos a través de eclipse.iniEDITAR 2: actualización de eclipse a la versión: 4.7.1a (Demasiadas imágenes en esta publicación ya)EDITAR 3: se verificaron los JDK dobles en el proyecto y / o las preferencias de Eclipse (Enlace de imágen)EDITAR 4: Reconstrucción del índice de Java (no funcionó), habilitandoNew Java index y reconstruir de nuevo: funcionó durante unos 3 minutos, pero luego apareció este error y volvieron los problemas técnicos:java.lang.ClassCastException mientras construyeEDITAR 4: Eliminando JDK 9 de la biblioteca predeterminada y volviéndolo a agregar, lo mismo desde arriba, pero esta vez arrojó el error:java.lang.NullPointerException en el espacio de trabajo, y el error de cadena sigue ocurriendo, incluso después de reiniciar el IDE ... (Por cierto,esta advertencia apareció a la palabra clave del paquete, no estoy seguro si ya estaba aquí antes ...)

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