code: public boolean isFinished(final ProcessorGraphNode processorGraphNode) {
          this.processorLock.lock();
          try {
              return this.executedProcessors.containsKey(processorGraphNode.getProcessor());
          } finally {
              this.processorLock.unlock();
          }
      }
docs: Return true if the processor of the node has previously been executed.
  
  @param processorGraphNode the node to test.