Package org.springframework.data.cassandra.core.cql

Interface RowCallbackHandler

Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public interface RowCallbackHandler
An interface used by CqlTemplate for processing rows of a ResultSet on a per-row basis. Implementations of this interface perform the actual work of processing each row but don't need to worry about exception handling. DriverExceptions will be caught and handled by the calling CqlTemplate.

In contrast to a ResultSetExtractor, a RowCallbackHandler object is typically stateful: It keeps the result state within the object, to be available for later inspection.

Consider using a RowMapper instead if you need to map exactly one result object per row, assembling them into a List.

Author:
Mark Paluch
See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    processRow(com.datastax.oss.driver.api.core.cql.Row row)
    Implementations must implement this method to process each row of data in the ResultSet.

  • Method Details

    • processRow

      void processRow(com.datastax.oss.driver.api.core.cql.Row row) throws com.datastax.oss.driver.api.core.DriverException
      Implementations must implement this method to process each row of data in the ResultSet. This method is only supposed to extract values of the current row.

      Exactly what the implementation chooses to do is up to it: A trivial implementation might simply count rows, while another implementation might build an XML document.

      Parameters:
      row - the Row to process (pre-initialized for the current row).
      Throws:
      com.datastax.oss.driver.api.core.DriverException - if a DriverException is encountered getting column values (that is, there's no need to catch DriverException).