@Override
 public int getRightId(int wordId) {
   return tokenInfoBuffer.lookupTokenInfo(wordId, RIGHT_ID);
 }
 @Override
 public int getWordCost(int wordId) {
   return tokenInfoBuffer.lookupTokenInfo(wordId, WORD_COST);
 }
 @Override
 public int getLeftId(int wordId) {
   return tokenInfoBuffer.lookupTokenInfo(wordId, LEFT_ID);
 }