code: private Map<String, Accumulator<?, ?>> deserializeAccumulators(TaskExecutionState state) {
  		AccumulatorSnapshot serializedAccumulators = state.getAccumulators();
  
  		if (serializedAccumulators != null) {
  			try {
  				return serializedAccumulators.deserializeUserAccumulators(userClassLoader);
  			}
  			catch (Throwable t) {
  				// we catch Throwable here to include all form of linking errors that may
  				// occur if user classes are missing in the classpath
  				LOG.error("Failed to deserialize final accumulator results.", t);
  			}
  		}
  		return null;
  	}
docs: Deserializes accumulators from a task state update.
  
  <p>This method never throws an exception!
  
  @param state The task execution state from which to deserialize the accumulators.
  @return The deserialized accumulators, of null, if there are no accumulators or an error occurred.