Bug 127861 [DataBinding] Mark API provisional
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/internal/databinding/CollectionBinding.java
copyType = BindingEvent.EVENT_COPY_TO_TARGET;
		   }
		   BindingEvent e = new BindingEvent(changeEvent, copyType, BindingEvent.PIPELINE_AFTER_GET);
		   e.originalValue = source.getElements();
		   if (failure(errMsg(fireBindingEvent(e)))) {
			   return;
		   }
		   
           destination.setElements((List)e.originalValue);
           e.pipelinePosition = BindingEvent.PIPELINE_AFTER_CHANGE;
		   if (failure(errMsg(fireBindingEvent(e)))) {
			   return;
		   }
		} finally {
			updating = false;
		}
	}
	private String errMsg(String validationError) {
		context.updatePartialValidationError(targetChangeListener, null);
		context.updateValidationError(targetChangeListener, validationError);
		return validationError;
	}
	
	private boolean failure(String errorMessage) {
		if (errorMessage != null) {
			return true;
		}
		return false;
	}}