title: Problems occurred when invoking code from plug-in: "org.eclipse.jface"
body: <p>I've got a new Java project at Eclipse from SVN and just tried to open the project in the Eclipse's Project Explorer window and received this error:</p>
  
  <blockquote>
    <p>Problems occurred when invoking code from plug-in: <code>"org.eclipse.jface"</code>.</p>
  </blockquote>
  
  <p>How could I fix that issue?</p>
  
  <p><strong>Exception Stack Trace:</strong> </p>
  
  <pre><code>java.lang.NullPointerException
      at org.jboss.ide.eclipse.as.classpath.core.ejb3.EJB3ClasspathContainer.getClasspathEntries(EJB3ClasspathContainer.java:115)
      at org.eclipse.jdt.internal.core.JavaProject.resolveClasspath(JavaProject.java:2695)
      at org.eclipse.jdt.internal.core.JavaProject.resolveClasspath(JavaProject.java:2853)
      at org.eclipse.jdt.internal.core.JavaProject.getResolvedClasspath(JavaProject.java:1958)
      at org.eclipse.jdt.internal.core.PackageFragmentRoot.getRawClasspathEntry(PackageFragmentRoot.java:547)
      at org.eclipse.jdt.internal.corext.buildpath.ClasspathModifier.isExcluded(ClasspathModifier.java:485)
      at org.eclipse.jdt.internal.ui.wizards.buildpaths.newsourcepage.IncludeToBuildpathAction.canHandle(IncludeToBuildpathAction.java:170)
      at org.eclipse.jdt.internal.ui.wizards.buildpaths.newsourcepage.BuildpathModifierAction.selectionChanged(BuildpathModifierAction.java:101)
      at org.eclipse.jface.viewers.Viewer$2.run(Viewer.java:164)
      at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
      at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
      at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
      at org.eclipse.jface.viewers.Viewer.fireSelectionChanged(Viewer.java:162)
      at org.eclipse.jface.viewers.StructuredViewer.updateSelection(StructuredViewer.java:2188)
      at org.eclipse.jface.viewers.StructuredViewer.handleSelect(StructuredViewer.java:1211)
      at org.eclipse.ui.navigator.CommonViewer.handleSelect(CommonViewer.java:478)
      at org.eclipse.jface.viewers.StructuredViewer$4.widgetSelected(StructuredViewer.java:1241)
      at org.eclipse.jface.util.OpenStrategy.fireSelectionEvent(OpenStrategy.java:239)
      at org.eclipse.jface.util.OpenStrategy.access$4(OpenStrategy.java:233)
      at org.eclipse.jface.util.OpenStrategy$1.handleEvent(OpenStrategy.java:403)
      at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
      at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4128)
      at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1457)
      at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1480)
      at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1465)
      at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:1270)
      at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3974)
      at org.eclipse.swt.widgets.Display.applicationNextEventMatchingMask(Display.java:4875)
      at org.eclipse.swt.widgets.Display.applicationProc(Display.java:5226)
      at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
      at org.eclipse.swt.widgets.Widget.callSuper(Widget.java:220)
      at org.eclipse.swt.widgets.Widget.mouseDownSuper(Widget.java:1092)
      at org.eclipse.swt.widgets.Tree.mouseDownSuper(Tree.java:2052)
      at org.eclipse.swt.widgets.Widget.mouseDown(Widget.java:1084)
      at org.eclipse.swt.widgets.Control.mouseDown(Control.java:2528)
      at org.eclipse.swt.widgets.Tree.mouseDown(Tree.java:2007)
      at org.eclipse.swt.widgets.Display.windowProc(Display.java:5471)
      at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
      at org.eclipse.swt.widgets.Widget.callSuper(Widget.java:220)
      at org.eclipse.swt.widgets.Widget.windowSendEvent(Widget.java:2095)
      at org.eclipse.swt.widgets.Shell.windowSendEvent(Shell.java:2253)
      at org.eclipse.swt.widgets.Display.windowProc(Display.java:5535)
      at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
      at org.eclipse.swt.widgets.Display.applicationSendEvent(Display.java:4989)
      at org.eclipse.swt.widgets.Display.applicationProc(Display.java:5138)
      at org.eclipse.swt.internal.cocoa.OS.objc_msgSend(Native Method)
      at org.eclipse.swt.internal.cocoa.NSApplication.sendEvent(NSApplication.java:128)
      at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3610)
      at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2701)
      at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2665)
      at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2499)
      at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:679)
      at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
      at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:668)
      at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
      at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:123)
      at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
      at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
      at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
      at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:344)
      at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
      at java.lang.reflect.Method.invoke(Method.java:597)
      at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:622)
      at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)
      at org.eclipse.equinox.launcher.Main.run(Main.java:1410)
  </code></pre>
  
  <p><strong>Session Data:</strong> </p>
  
  <pre><code>eclipse.buildId=M20120208-0800
  java.version=1.6.0_37
  java.vendor=Apple Inc.
  BootLoader constants: OS=macosx, ARCH=x86_64, WS=cocoa, NL=en_US
  Framework arguments:  -product org.eclipse.epp.package.jee.product -keyring /Users/saraiva/.eclipse_keyring -showlocation
  Command-line arguments:  -os macosx -ws cocoa -arch x86_64 -product org.eclipse.epp.package.jee.product -keyring /Users/saraiva/.eclipse_keyring -showlocation
  </code></pre>