Bug 96917 [implementation] If two editors use the 2.x-compatible API, one or both doesn't work
At least one problem is that 3.0 installs partitioners for every editor that might possibly edit a file, but each editor expects its own partitioner to be installed. Leading to the famous white screen with blue line.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitDocumentProvider.java
}
			}
			/*
			 * @see IJavaAnnotation#getOverlaidIterator()
			 */
			public Iterator getOverlaidIterator() {
				if (fOverlaids != null)
					return fOverlaids.iterator();
				return null;
			}
			/*
			 * @see org.eclipse.jdt.internal.ui.javaeditor.IJavaAnnotation#getCompilationUnit()
			 */
			public ICompilationUnit getCompilationUnit() {
				return fCompilationUnit;
			}
		}
		/**
		 * Internal structure for mapping positions to some value.
		 * The reason for this specific structure is that positions can
		 * change over time. Thus a lookup is based on value and not
		 * on hash value.
		 */
		protected static class ReverseMap {
			static class Entry {
				Position fPosition;
				Object fValue;
			}
			private List fList= new ArrayList(2);
			private int fAnchor= 0;