Eclipse无法识别.java文件

短版：

• 无法启动eclipse
• 删除了一些快照和树文件
• 可以打开eclipse但找不到我的文件“无法确定[project name]/[file path]/[file name]的URI”
• 无法重新导入它们，因为Eclipse无法识别.java文件

长版本： 这一切都是从今天早上的错误消息开始的（以最新的错误消息为准）：

这似乎造成了问题：
！消息工作区已退出，但在上一个会话中未保存更改；正在刷新工作区以恢复更改。

我通过删除（并备份）.snap和.tree文件解决了这个问题。：/br/>

这导致了我现在面临的下一个问题。 我试图通过重新导入我的项目来解决这个问题，正如本文中建议的那样：

---

顺便说一句，我把我的项目组织成java工作集。不知道这是否有什么区别。

按照这两位的建议解决了问题：

杰伊： “所以我参加聚会有点晚了，但我在重新导入我的项目时解决了这个问题

在“文件->导入”下，选择“常规->将现有项目导入工作区”。在下一页，您将工作区目录设置为要导入的根目录，这将给您一个类似“工作区中已存在某些项目”的警告。忽略此项，然后单击“完成”。之后，所有我的项目将返回我的工作区

祝你好运”

及

雷基尼兹： 取消选中“将项目复制到工作区”复选框，然后单击“刷新”按钮，您将能够导入项目。

---

如果使用工作集，如果您备份了整个

。metadata

文件夹，请记住重新导入正确文件夹中的所有项目…

通过使用

-clean

选项启动Eclipse来恢复它并遵循文档，而不是按照堆栈溢出的答案删除不打算手动删除的随机文件。如果

-clean

不起作用，请切换到新的工作区并从旧工作区导入项目。您的意思是在问题开始之前进行备份吗？那我就没有了。我只有手动删除的文件。是的，在问题开始之前。无论如何，您可以尝试

-clean

。你有没有告诉那些建议删除随机文件的人它不起作用并造成损害？我不能回复帖子，因为我是个新手，没有足够的声誉。。。我会退房-清洁并尝试一下。

!SESSION 2020-11-26 10:13:32.039 -----------------------------------------------
eclipse.buildId=4.17.0.I20200902-1800
java.version=14.0.2
java.vendor=Oracle Corporation
BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=de_DE
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.oomph.util 4 0 2020-11-26 10:13:33.112
!MESSAGE FrameworkEvent ERROR
!STACK 0
org.osgi.framework.BundleException: Could not resolve module: org.eclipse.oomph.util [879]
  Another singleton bundle selected: osgi.identity; type="osgi.bundle"; version:Version="1.16.0.v20200917-0735"; osgi.identity="org.eclipse.oomph.util"; singleton:="true"

    at org.eclipse.osgi.container.Module.start(Module.java:463)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel$2.run(ModuleContainer.java:1845)
    at org.eclipse.osgi.internal.framework.EquinoxContainerAdaptor$1$1.execute(EquinoxContainerAdaptor.java:136)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1838)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.incStartLevel(ModuleContainer.java:1779)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.doContainerStartLevel(ModuleContainer.java:1743)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1665)
    at org.eclipse.osgi.container.ModuleContainer$ContainerStartLevel.dispatchEvent(ModuleContainer.java:1)
    at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:234)
    at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:345)

!ENTRY org.eclipse.core.resources 2 10035 2020-11-26 10:13:44.879
!MESSAGE The workspace exited with unsaved changes in the previous session; refreshing workspace to recover changes.

!ENTRY org.apache.felix.scr 4 0 2020-11-26 10:13:44.894
!MESSAGE bundle org.apache.felix.scr:2.1.16.v20200110-1820 (552)Error while disposing components of bundle org.eclipse.core.resources:3.13.800.v20200706-2152 (591)
!STACK 0
java.lang.IllegalStateException: BundleContext is no longer valid org.eclipse.core.resources_3.13.800.v20200706-2152 [591]
    at org.eclipse.osgi.internal.framework.BundleContextImpl.checkValid(BundleContextImpl.java:1027)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.ungetService(BundleContextImpl.java:697)
    at org.apache.felix.scr.impl.logger.LogServiceEnabledLogger$1.removedService(LogServiceEnabledLogger.java:79)
    at org.osgi.util.tracker.ServiceTracker$Tracked.customizerRemoved(ServiceTracker.java:969)
    at org.osgi.util.tracker.ServiceTracker$Tracked.customizerRemoved(ServiceTracker.java:1)
    at org.osgi.util.tracker.AbstractTracked.untrack(AbstractTracked.java:341)
    at org.osgi.util.tracker.ServiceTracker.close(ServiceTracker.java:380)
    at org.apache.felix.scr.impl.logger.LogServiceEnabledLogger.close(LogServiceEnabledLogger.java:91)
    at org.apache.felix.scr.impl.logger.BundleLogger.close(BundleLogger.java:28)
    at org.apache.felix.scr.impl.BundleComponentActivator.dispose(BundleComponentActivator.java:531)
    at org.apache.felix.scr.impl.Activator.disposeComponents(Activator.java:429)
    at org.apache.felix.scr.impl.Activator.access$300(Activator.java:49)
    at org.apache.felix.scr.impl.Activator$ScrExtension.destroy(Activator.java:292)
    at org.apache.felix.scr.impl.AbstractExtender$1.run(AbstractExtender.java:216)
    at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at org.apache.felix.scr.impl.AbstractExtender.destroyExtension(AbstractExtender.java:238)
    at org.apache.felix.scr.impl.AbstractExtender.bundleChanged(AbstractExtender.java:132)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.dispatchEvent(BundleContextImpl.java:945)
    at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:234)
    at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:151)
    at org.eclipse.osgi.internal.framework.EquinoxEventPublisher.publishBundleEventPrivileged(EquinoxEventPublisher.java:232)
    at org.eclipse.osgi.internal.framework.EquinoxEventPublisher.publishBundleEvent(EquinoxEventPublisher.java:138)
    at org.eclipse.osgi.internal.framework.EquinoxEventPublisher.publishBundleEvent(EquinoxEventPublisher.java:130)
    at org.eclipse.osgi.internal.framework.EquinoxContainerAdaptor.publishModuleEvent(EquinoxContainerAdaptor.java:217)
    at org.eclipse.osgi.container.Module.publishEvent(Module.java:499)
    at org.eclipse.osgi.container.Module.doStart(Module.java:611)
    at org.eclipse.osgi.container.Module.start(Module.java:468)
    at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:506)
    at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:117)
    at org.eclipse.osgi.internal.loader.classpath.ClasspathManager.findLocalClass(ClasspathManager.java:572)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.findLocalClass(ModuleClassLoader.java:346)
    at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:398)
    at org.eclipse.osgi.internal.loader.sources.SingleSourcePackage.loadClass(SingleSourcePackage.java:41)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:473)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:171)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
    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:401)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
    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:657)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:594)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1465)

!ENTRY org.eclipse.osgi 4 0 2020-11-26 10:13:44.894
!MESSAGE An error occurred while automatically activating bundle org.eclipse.core.resources (591).
!STACK 0
org.osgi.framework.BundleException: Exception in org.eclipse.core.resources.ResourcesPlugin.start() of bundle org.eclipse.core.resources.
    at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:835)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.start(BundleContextImpl.java:763)
    at org.eclipse.osgi.internal.framework.EquinoxBundle.startWorker0(EquinoxBundle.java:1011)
    at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.startWorker(EquinoxBundle.java:365)
    at org.eclipse.osgi.container.Module.doStart(Module.java:605)
    at org.eclipse.osgi.container.Module.start(Module.java:468)
    at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:506)
    at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:117)
    at org.eclipse.osgi.internal.loader.classpath.ClasspathManager.findLocalClass(ClasspathManager.java:572)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.findLocalClass(ModuleClassLoader.java:346)
    at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:398)
    at org.eclipse.osgi.internal.loader.sources.SingleSourcePackage.loadClass(SingleSourcePackage.java:41)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:473)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:171)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
    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:401)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
    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:657)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:594)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1465)
Caused by: org.eclipse.core.internal.dtree.ObjectNotFoundException: Tree element '/04-HA-Advanced-StopWatch-Muster/src/idh/java/ha/StopWatch.java' not found.
    at org.eclipse.core.internal.dtree.AbstractDataTree.handleNotFound(AbstractDataTree.java:260)
    at org.eclipse.core.internal.dtree.DeltaDataTree.getData(DeltaDataTree.java:599)
    at org.eclipse.core.internal.dtree.DataDeltaNode.asBackwardDelta(DataDeltaNode.java:54)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.DataDeltaNode.asBackwardDelta(DataDeltaNode.java:51)
    at org.eclipse.core.internal.dtree.DeltaDataTree.asBackwardDelta(DeltaDataTree.java:91)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:835)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:834)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:811)
    at org.eclipse.core.internal.watson.ElementTree.immutable(ElementTree.java:522)
    at org.eclipse.core.internal.resources.SaveManager.restore(SaveManager.java:731)
    at org.eclipse.core.internal.resources.SaveManager.startup(SaveManager.java:1555)
    at org.eclipse.core.internal.resources.Workspace.startup(Workspace.java:2452)
    at org.eclipse.core.internal.resources.Workspace.open(Workspace.java:2210)
    at org.eclipse.core.resources.ResourcesPlugin.start(ResourcesPlugin.java:489)
    at org.eclipse.osgi.internal.framework.BundleContextImpl$2.run(BundleContextImpl.java:814)
    at org.eclipse.osgi.internal.framework.BundleContextImpl$2.run(BundleContextImpl.java:1)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:554)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:806)
    ... 27 more
Root exception:
org.eclipse.core.internal.dtree.ObjectNotFoundException: Tree element '/04-HA-Advanced-StopWatch-Muster/src/idh/java/ha/StopWatch.java' not found.
    at org.eclipse.core.internal.dtree.AbstractDataTree.handleNotFound(AbstractDataTree.java:260)
    at org.eclipse.core.internal.dtree.DeltaDataTree.getData(DeltaDataTree.java:599)
    at org.eclipse.core.internal.dtree.DataDeltaNode.asBackwardDelta(DataDeltaNode.java:54)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.DataDeltaNode.asBackwardDelta(DataDeltaNode.java:51)
    at org.eclipse.core.internal.dtree.DeltaDataTree.asBackwardDelta(DeltaDataTree.java:91)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:835)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:834)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:811)
    at org.eclipse.core.internal.watson.ElementTree.immutable(ElementTree.java:522)
    at org.eclipse.core.internal.resources.SaveManager.restore(SaveManager.java:731)
    at org.eclipse.core.internal.resources.SaveManager.startup(SaveManager.java:1555)
    at org.eclipse.core.internal.resources.Workspace.startup(Workspace.java:2452)
    at org.eclipse.core.internal.resources.Workspace.open(Workspace.java:2210)
    at org.eclipse.core.resources.ResourcesPlugin.start(ResourcesPlugin.java:489)
    at org.eclipse.osgi.internal.framework.BundleContextImpl$2.run(BundleContextImpl.java:814)
    at org.eclipse.osgi.internal.framework.BundleContextImpl$2.run(BundleContextImpl.java:1)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:554)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:806)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.start(BundleContextImpl.java:763)
    at org.eclipse.osgi.internal.framework.EquinoxBundle.startWorker0(EquinoxBundle.java:1011)
    at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.startWorker(EquinoxBundle.java:365)
    at org.eclipse.osgi.container.Module.doStart(Module.java:605)
    at org.eclipse.osgi.container.Module.start(Module.java:468)
    at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:506)
    at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:117)
    at org.eclipse.osgi.internal.loader.classpath.ClasspathManager.findLocalClass(ClasspathManager.java:572)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.findLocalClass(ModuleClassLoader.java:346)
    at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:398)
    at org.eclipse.osgi.internal.loader.sources.SingleSourcePackage.loadClass(SingleSourcePackage.java:41)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:473)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:171)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
    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:401)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
    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:657)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:594)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1465)

!ENTRY org.eclipse.osgi 4 0 2020-11-26 10:13:44.910
!MESSAGE Application error
!STACK 1
java.lang.NoClassDefFoundError: org/eclipse/core/resources/IContainer
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
    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:401)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
    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:657)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:594)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1465)
Caused by: java.lang.ClassNotFoundException: An error occurred while automatically activating bundle org.eclipse.core.resources (591).
    at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:126)
    at org.eclipse.osgi.internal.loader.classpath.ClasspathManager.findLocalClass(ClasspathManager.java:572)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.findLocalClass(ModuleClassLoader.java:346)
    at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:398)
    at org.eclipse.osgi.internal.loader.sources.SingleSourcePackage.loadClass(SingleSourcePackage.java:41)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:473)
    at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:171)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
    ... 13 more
Caused by: org.osgi.framework.BundleException: Exception in org.eclipse.core.resources.ResourcesPlugin.start() of bundle org.eclipse.core.resources.
    at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:835)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.start(BundleContextImpl.java:763)
    at org.eclipse.osgi.internal.framework.EquinoxBundle.startWorker0(EquinoxBundle.java:1011)
    at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.startWorker(EquinoxBundle.java:365)
    at org.eclipse.osgi.container.Module.doStart(Module.java:605)
    at org.eclipse.osgi.container.Module.start(Module.java:468)
    at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:506)
    at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:117)
    ... 20 more
Caused by: org.eclipse.core.internal.dtree.ObjectNotFoundException: Tree element '/04-HA-Advanced-StopWatch-Muster/src/idh/java/ha/StopWatch.java' not found.
    at org.eclipse.core.internal.dtree.AbstractDataTree.handleNotFound(AbstractDataTree.java:260)
    at org.eclipse.core.internal.dtree.DeltaDataTree.getData(DeltaDataTree.java:599)
    at org.eclipse.core.internal.dtree.DataDeltaNode.asBackwardDelta(DataDeltaNode.java:54)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.NoDataDeltaNode.asBackwardDelta(NoDataDeltaNode.java:63)
    at org.eclipse.core.internal.dtree.DataDeltaNode.asBackwardDelta(DataDeltaNode.java:51)
    at org.eclipse.core.internal.dtree.DeltaDataTree.asBackwardDelta(DeltaDataTree.java:91)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:835)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:834)
    at org.eclipse.core.internal.dtree.DeltaDataTree.reroot(DeltaDataTree.java:811)
    at org.eclipse.core.internal.watson.ElementTree.immutable(ElementTree.java:522)
    at org.eclipse.core.internal.resources.SaveManager.restore(SaveManager.java:731)
    at org.eclipse.core.internal.resources.SaveManager.startup(SaveManager.java:1555)
    at org.eclipse.core.internal.resources.Workspace.startup(Workspace.java:2452)
    at org.eclipse.core.internal.resources.Workspace.open(Workspace.java:2210)
    at org.eclipse.core.resources.ResourcesPlugin.start(ResourcesPlugin.java:489)
    at org.eclipse.osgi.internal.framework.BundleContextImpl$2.run(BundleContextImpl.java:814)
    at org.eclipse.osgi.internal.framework.BundleContextImpl$2.run(BundleContextImpl.java:1)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:554)
    at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:806)
    ... 27 more