org.springframework.data.cassandra.core.cql

Interface ReactiveResultSetExtractor<T>

All Known Implementing Classes:

ReactiveRowMapperResultSetExtractor

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 ReactiveResultSetExtractor<T>

Callback interface used by ReactiveCqlTemplate's query methods. Implementations of this interface perform the actual work of extracting results from a ReactiveResultSet, but don't need to worry about exception handling. DriverExceptions will be caught and handled by the calling ReactiveCqlTemplate.

This interface is mainly used within the CQL framework itself. A RowMapper is usually a simpler choice for ReactiveResultSet processing, mapping one result object per row instead of one result object for the entire ReactiveResultSet.

Note: ReactiveResultSetExtractor object is typically stateless and thus reusable, as long as it doesn't access stateful resources or keep result state within the object.

Since:

2.0

Author:

Mark Paluch

See Also:

ReactiveCqlTemplate, RowCallbackHandler, RowMapper

Method Summary

Modifier and Type	Method and Description
org.reactivestreams.Publisher<T>	extractData(ReactiveResultSet resultSet) Implementations must implement this method to process the entire ReactiveResultSet.

Method Detail

extractData

org.reactivestreams.Publisher<T> extractData(ReactiveResultSet resultSet)
                                      throws com.datastax.oss.driver.api.core.DriverException,
                                             DataAccessException

Implementations must implement this method to process the entire ReactiveResultSet.

Parameters:

resultSet - ReactiveResultSet to extract data from, must not be null.

Returns:

an arbitrary result object Publisher.

Throws:

com.datastax.oss.driver.api.core.DriverException - if a DriverException is encountered getting column values or navigating (that is, there's no need to catch DriverException).

DataAccessException - in case of custom exceptions.