Bug 4369 F2 should work even if "Hide Text Hover" is enabled
- enable "Hide Text Hover" - position the cursor on a type - press F2 observe: nothing happens although I explicitly requested JavaDoc help.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
fIsActive= true;
					
					fBracketPosition.isDeleted= false;
					fBracketPosition.offset= pair.getOffset();
					fBracketPosition.length= pair.getLength();
					fAnchor= fMatcher.getAnchor();
					
					fTextWidget.addPaintListener(this);
					fManager.manage(fBracketPosition);
					handleDrawRequest(null);
				}
			}
			
			public void paintControl(PaintEvent event) {
				if (fTextWidget != null)
					handleDrawRequest(event.gc);
			}
			
			private void handleDrawRequest(GC gc) {
				IRegion region= fSourceViewer.getVisibleRegion();
				int offset= fBracketPosition.getOffset();
				int length= fBracketPosition.getLength();
				
				if (region.getOffset() <= offset && region.getOffset() + region.getLength() >= offset + length) {
					offset -= region.getOffset();
					if (fMatcher.RIGHT == fAnchor)
						draw(gc, offset, 1);
					else 
						draw(gc, offset + length -1, 1);