Bug 21047 code formatter availability inconsistent
Sometimes the hotkey (ctrl-shift-f) and the menu entry for formatting the source code are disabled, while the entry in the context menu is enabled and works as expected. I didn't find any patterns on when this occurs till now.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
private List fTextConverters;
		private OverviewRuler fOverviewRuler;
		private boolean fIsOverviewRulerVisible;
		
		private AbstractHoverInformationControlManager fOverviewRulerHoveringController;
		private boolean fIgnoreTextConverters= false;
		
		private IVerticalRuler fCachedVerticalRuler;
		private boolean fCachedIsVerticalRulerVisible;
		
		
		public AdaptedSourceViewer(Composite parent, IVerticalRuler ruler, int styles) {
			super(parent, ruler, styles, CompilationUnitEditor.this);
			
			fCachedVerticalRuler= ruler;
			fCachedIsVerticalRulerVisible= (ruler != null);
			fOverviewRuler= new OverviewRuler(VERTICAL_RULER_WIDTH);
			
			delayedCreateControl(parent, styles);
		}