code: public synchronized void updateAssignment(String primaryKey, 
                                                String secondaryKey,
                                                int clusterId) {
          // Get the word and part of speech information.
          int splitIndex = secondaryKey.lastIndexOf(".");
          String wordPos = secondaryKey.substring(0, splitIndex);
  
          // Print out the answer key.
          writer.printf("%s %s %s.%d\n",
                        wordPos, secondaryKey, wordPos, clusterId);
      }
docs: {@inheritDoc}