Bug 26547 Automatic closing of strings is not smart enough
Trying to add strings around an existing identifier is highly annoying when the Automatically close Strings option is set. For example, when I try to add Strings around: System.out.println(a) before a then I get two quotes. I suggest the rule to not close a string when there is a letter that belongs to an identifier to the left or right.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
if (!fIgnoreTextConverters && fTextConverters != null) {
				for (Iterator e = fTextConverters.iterator(); e.hasNext();)
					((ITextConverter) e.next()).customizeDocumentCommand(getDocument(), command);
			}
			fIgnoreTextConverters= false;
		}
		
		public IVerticalRuler getVerticalRuler() {
			return fCachedVerticalRuler;
		}
		
		public boolean isVerticalRulerVisible() {
			return fCachedIsVerticalRulerVisible;
		}
		
		public OverviewRuler getOverviewRuler() {
			return fOverviewRuler;
		}
		
		/*
		 * @see TextViewer#createControl(Composite, int)
		 */
		protected void createControl(Composite parent, int styles) {
			
		}
		
		protected void delayedCreateControl(Composite parent, int styles) {
			
			super.createControl(parent, styles);