docs: public int getTransactionCount() {
          if (isFiltered()) {
  
              int ltransactionCount = transactionCount;
              if (ltransactionCount < 0) {
                  ltransactionCount = 0;
  
                  for (int i = filteredBlock.getFilteredTransactionsCount() - 1; i >= 0; --i) {
                      FilteredTransaction filteredTransactions = filteredBlock.getFilteredTransactions(i);
                      Common.HeaderType type = filteredTransactions.getType();
                      if (type == Common.HeaderType.ENDORSER_TRANSACTION) {
                          ++ltransactionCount;
                      }
                  }
                  transactionCount = ltransactionCount;
              }
  
              return transactionCount;
          }
          int ltransactionCount = transactionCount;
          if (ltransactionCount < 0) {
  
              ltransactionCount = 0;
              for (int i = getEnvelopeCount() - 1; i >= 0; --i) {
                  try {
                      EnvelopeInfo envelopeInfo = getEnvelopeInfo(i);
                      if (envelopeInfo.getType() == TRANSACTION_ENVELOPE) {
                          ++ltransactionCount;
                      }
                  } catch (InvalidProtocolBufferException e) {
                      throw new InvalidProtocolBufferRuntimeException(e);
                  }
              }
              transactionCount = ltransactionCount;
          }
          return transactionCount;
      }