org.apache.flink.batch.connectors.cassandra

Class CassandraOutputFormatBase<OUT>

java.lang.Object

org.apache.flink.api.common.io.RichOutputFormat<OUT>

org.apache.flink.batch.connectors.cassandra.CassandraOutputFormatBase<OUT>

Type Parameters:

OUT - Type of the elements to write.

All Implemented Interfaces:

Serializable, OutputFormat<OUT>

Direct Known Subclasses:

CassandraRowOutputFormat, CassandraTupleOutputFormat

public abstract class CassandraOutputFormatBase<OUT>
extends RichOutputFormat<OUT>

CassandraOutputFormatBase is the common abstract class for writing into Apache Cassandra.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
CassandraOutputFormatBase(String insertQuery, ClusterBuilder builder)

Method Summary

Modifier and Type	Method and Description
void	close() Closes all resources used.
void	configure(Configuration parameters) Configures this output format.
protected abstract Object[]	extractFields(OUT record)
protected void	onWriteFailure(Throwable t) Callback that is invoked when failing to write to Cassandra.
protected void	onWriteSuccess(com.datastax.driver.core.ResultSet ignored) Callback that is invoked after a record is written to Cassandra successfully.
void	open(int taskNumber, int numTasks) Opens a Session to Cassandra and initializes the prepared statement.
void	writeRecord(OUT record) Adds a record to the output.

Methods inherited from class org.apache.flink.api.common.io.RichOutputFormat

getRuntimeContext, setRuntimeContext

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CassandraOutputFormatBase

public CassandraOutputFormatBase(String insertQuery,
                                 ClusterBuilder builder)

Method Detail

configure

public void configure(Configuration parameters)

Description copied from interface: OutputFormat

Configures this output format. Since output formats are instantiated generically and hence parameterless, this method is the place where the output formats set their basic fields based on configuration values.

This method is always called first on a newly instantiated output format.

Parameters:

parameters - The configuration with all parameters.

open

public void open(int taskNumber,
                 int numTasks)
          throws IOException

Opens a Session to Cassandra and initializes the prepared statement.

Parameters:

taskNumber - The number of the parallel instance.

numTasks - The number of parallel tasks.

Throws:

IOException - Thrown, if the output could not be opened due to an I/O problem.

writeRecord

public void writeRecord(OUT record)
                 throws IOException

Description copied from interface: OutputFormat

Adds a record to the output.

When this method is called, the output format it guaranteed to be opened.

Parameters:

record - The records to add to the output.

Throws:

IOException - Thrown, if the records could not be added to to an I/O problem.

extractFields

protected abstract Object[] extractFields(OUT record)

onWriteSuccess

protected void onWriteSuccess(com.datastax.driver.core.ResultSet ignored)

Callback that is invoked after a record is written to Cassandra successfully.

Subclass can override to provide its own logic.

Parameters:

ignored - the result.

onWriteFailure

protected void onWriteFailure(Throwable t)

Callback that is invoked when failing to write to Cassandra. Current implementation will record the exception and fail the job upon next record.

Subclass can override to provide its own failure handling logic.

Parameters:

t - the exception

close

public void close()
           throws IOException

Closes all resources used.

Throws:

IOException - Thrown, if the input could not be closed properly.