code: public String sql() {
          if (sb == null) {
              throw new AbacusException("This SQLBuilder has been closed after sql() was called previously");
          }
  
          init(true);
  
          String sql = null;
  
          try {
              sql = sb.toString();
          } finally {
              Objectory.recycle(sb);
              sb = null;
  
              activeStringBuilderCounter.decrementAndGet();
          }
  
          if (logger.isDebugEnabled()) {
              logger.debug(sql);
          }
  
          return sql;
      }
docs: This SQLBuilder will be closed after <code>sql()</code> is called.
  
  @return