title: Decoration Calculation Error on Eclipse (STS)
body: <p>When I try to open an xml file on STS I get an error.</p>
  <p><a href="https://i.stack.imgur.com/RKAhz.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/RKAhz.png" alt="enter image description here" /></a></p>
  <p>The contents are as follows:</p>
  <p>An internal error occurred during: &quot;Decoration Calculation&quot;.
  org/springframework/tooling/boot/ls/xml/XMLRootElementContentDescriber2$QualifiedElement</p>
  <p>When I looked at the log in the metadata, the following error message was output.</p>
  <pre><code>!ENTRY org.eclipse.jface 4 2 2020-12-24 20:20:29.699
  !MESSAGE Problems occurred when invoking code from plug-in: &quot;org.eclipse.jface&quot;.
  !STACK 0
  java.lang.NoClassDefFoundError: org/springframework/tooling/boot/ls/xml/XMLRootElementContentDescriber2$QualifiedElement
      at org.springframework.tooling.boot.ls.xml.XMLRootElementContentDescriber2.setInitializationData(XMLRootElementContentDescriber2.java:281)
      at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:254)
      at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:63)
      at org.eclipse.core.internal.content.ContentType.getDescriber(ContentType.java:293)
      at org.eclipse.core.internal.content.ContentTypeCatalog.collectMatchingByContents(ContentTypeCatalog.java:235)
      at org.eclipse.core.internal.content.ContentTypeCatalog.internalFindContentTypesFor(ContentTypeCatalog.java:455)
      at org.eclipse.core.internal.content.ContentTypeCatalog.internalFindContentTypesFor(ContentTypeCatalog.java:514)
      at org.eclipse.core.internal.content.ContentTypeCatalog.getDescriptionFor(ContentTypeCatalog.java:398)
      at org.eclipse.core.internal.content.ContentTypeCatalog.getDescriptionFor(ContentTypeCatalog.java:412)
      at org.eclipse.core.internal.content.ContentTypeMatcher.getDescriptionFor(ContentTypeMatcher.java:82)
      at org.eclipse.core.internal.resources.ContentDescriptionManager.readDescription(ContentDescriptionManager.java:455)
      at org.eclipse.core.internal.resources.ContentDescriptionManager.getDescriptionFor(ContentDescriptionManager.java:364)
      at org.eclipse.core.internal.resources.File.getContentDescription(File.java:266)
      at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.isClassFile(EditorUtility.java:656)
      at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:169)
      at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:287)
      at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:252)
      at org.eclipse.jdt.ui.actions.SelectionDispatchAction.dispatchRun(SelectionDispatchAction.java:274)
      at org.eclipse.jdt.ui.actions.SelectionDispatchAction.run(SelectionDispatchAction.java:252)
      at org.eclipse.jdt.internal.ui.packageview.PackageExplorerActionGroup.handleOpen(PackageExplorerActionGroup.java:382)
      at org.eclipse.jdt.internal.ui.packageview.PackageExplorerPart$4.open(PackageExplorerPart.java:554)
      at org.eclipse.ui.OpenAndLinkWithEditorHelper$InternalListener.open(OpenAndLinkWithEditorHelper.java:48)
      at org.eclipse.jface.viewers.StructuredViewer$2.run(StructuredViewer.java:796)
      at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
      at org.eclipse.ui.internal.JFaceUtil.lambda$0(JFaceUtil.java:47)
      at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:176)
      at org.eclipse.jface.viewers.StructuredViewer.fireOpen(StructuredViewer.java:793)
      at org.eclipse.jface.viewers.StructuredViewer.handleOpen(StructuredViewer.java:1108)
      at org.eclipse.jface.util.OpenStrategy.fireOpenEvent(OpenStrategy.java:275)
      at org.eclipse.jface.util.OpenStrategy.access$2(OpenStrategy.java:270)
      at org.eclipse.jface.util.OpenStrategy$1.handleEvent(OpenStrategy.java:310)
      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:1056)
      at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3944)
      at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3547)
      at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1173)
      at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
      at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1062)
      at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:155)
      at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:635)
      at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
      at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:559)
      at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
      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(Unknown Source)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
      at java.lang.reflect.Method.invoke(Unknown Source)
      at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:660)
      at org.eclipse.equinox.launcher.Main.basicRun(Main.java:597)
      at org.eclipse.equinox.launcher.Main.run(Main.java:1468)
  </code></pre>
  <p>What is the problem? The STS version is 4.3.2.</p>