code: public synchronized void addBatch(String sql) throws SQLException {
  
          checkClosed();
  
          if (isEscapeProcessing) {
              sql = connection.nativeSQL(sql);
          }
  
          if (batchResultOut == null) {
              batchResultOut = Result.newBatchedExecuteRequest();
          }
          batchResultOut.getNavigator().add(new Object[] { sql });
      }
docs: <!-- start generic documentation -->
  Adds the given SQL command to the current list of commmands for this
  <code>Statement</code> object. The commands in this list can be
  executed as a batch by calling the method <code>executeBatch</code>.
  <P>
  (JDBC4 clarification:)<p>
  <B>NOTE:</B>  Support of an ability to batch updates is optional.
  
  <!-- end generic documentation -->
  
  <!-- start release-specific documentation -->
  <div class="ReleaseSpecificDocumentation">
  <h3>HSQLDB-Specific Information:</h3> <p>
  
  Starting with 1.7.2, this feature is supported.
  </div>
  <!-- end release-specific documentation -->
  
  @param sql typically this is a SQL <code>INSERT</code> or
  <code>UPDATE</code> statement
  (:JDBC4 modified)
  @exception SQLException if a database access error occurs,
  this method is called on a closed <code>Statement</code> or the
  driver does not support batch updates
  @see #executeBatch
  @since JDK 1.2 (JDK 1.1.x developers: read the overview
  for JDBCStatement)