code: public PreparedStatement getPreparedUpdate(String tableName, Update update) {
          synchronized (m_prepUpdateMap) {
              Map<Update, PreparedStatement> statementMap = m_prepUpdateMap.get(tableName);
              if (statementMap == null) {
                  statementMap = new HashMap<>();
                  m_prepUpdateMap.put(tableName, statementMap);
              }
              PreparedStatement prepState = statementMap.get(update);
              if (prepState == null) {
                  prepState = prepareUpdate(tableName, update);
                  statementMap.put(update, prepState);
              }
              return prepState;
          }
      }
docs: Get the given prepared statement for the given table and update. Upon
  first invocation for a given combo, the query is parsed and cached.
  
  @param tableName Name of table to customize update for.
  @param update    Inquiry {@link Update}.
  @return          PreparedStatement for given combo.