org.apache.flink.streaming.connectors.fs

Interface Writer<T>

Type Parameters:

T - The type of the elements that are being written by the sink.

All Superinterfaces:

Serializable

All Known Implementing Classes:

SequenceFileWriter, StringWriter

public interface Writer<T>
extends Serializable

An implementation of Writer is used in conjunction with a RollingSink to perform the actual writing to the bucket files.

Method Summary

Modifier and Type	Method and Description
void	close() Closes the Writer.
Writer<T>	duplicate() Duplicates the Writer.
void	flush() Flushes out any internally held data.
void	open(org.apache.hadoop.fs.FSDataOutputStream outStream) Initializes the Writer for a newly opened bucket file.
void	write(T element) Writes one element to the bucket file.

Method Detail

open

void open(org.apache.hadoop.fs.FSDataOutputStream outStream)
   throws IOException

Initializes the Writer for a newly opened bucket file. Any internal per-bucket initialization should be performed here.

Parameters:

outStream - The FSDataOutputStream for the newly opened file.

Throws:

IOException

flush

void flush()
    throws IOException

Flushes out any internally held data.

Throws:

IOException

close

void close()
    throws IOException

Closes the Writer. This must not close the FSDataOutputStream that was handed in in the open(org.apache.hadoop.fs.FSDataOutputStream) method. Only internally held state should be closed.

Throws:

IOException

write

void write(T element)
    throws IOException

Writes one element to the bucket file.

Throws:

IOException

duplicate

Writer<T> duplicate()

Duplicates the Writer. This is used to get one Writer for each parallel instance of the sink.