NPE while hovering in java editor in an SWT class

[Lulle74]

java.lang.NullPointerException: Cannot invoke "org.eclipse.core.resources.IResource.getProject()" because the return value of "org.eclipse.jdt.core.IJavaElement.getResource()" is null
	at org.eclipse.babel.tapiji.tools.java.ui.ConstantStringHover.initConstantStringAuditor(ConstantStringHover.java:54)
	at org.eclipse.babel.tapiji.tools.java.ui.ConstantStringHover.setEditor(ConstantStringHover.java:33)
	at org.eclipse.jdt.internal.ui.text.java.hover.BestMatchHover.checkTextHovers(BestMatchHover.java:86)
	at org.eclipse.jdt.internal.ui.text.java.hover.BestMatchHover.getHoverInfo2(BestMatchHover.java:152)
	at org.eclipse.jdt.internal.ui.text.java.hover.BestMatchHover.getHoverInfo2(BestMatchHover.java:130)
	at org.eclipse.jdt.internal.ui.text.java.hover.JavaEditorTextHoverProxy.getHoverInfo2(JavaEditorTextHoverProxy.java:89)
	at org.eclipse.jface.text.TextViewerHoverManager$1.run(TextViewerHoverManager.java:155)