code:   public void execute(FunctionContext context) {
      RegionFunctionContext rfc = (RegionFunctionContext) context;
      Set<String> keys = (Set<String>) rfc.getFilter();
  
      // Get local (primary) data for the context
      Region primaryDataSet = PartitionRegionHelper.getLocalDataForContext(rfc);
  
      if (this.cache.getLogger().fineEnabled()) {
        StringBuilder builder = new StringBuilder();
        builder.append("Function ").append(ID).append(" received request to touch ")
            .append(primaryDataSet.getFullPath()).append("->").append(keys);
        this.cache.getLogger().fine(builder.toString());
      }
  
      // Retrieve each value to update the lastAccessedTime.
      // Note: getAll is not supported on LocalDataSet.
      for (String key : keys) {
        primaryDataSet.get(key);
      }
  
      // Return result to get around NPE in LocalResultCollectorImpl
      context.getResultSender().lastResult(true);
    }
  
  