Package cz.o2.proxima.direct.core

Interface OnlineAttributeWriter

All Superinterfaces:

AttributeWriterBase, java.lang.AutoCloseable

All Known Subinterfaces:

CachedView

All Known Implementing Classes:

AbstractOnlineAttributeWriter, HttpWriter, JdbcOnlineAttributeWriter, KafkaWriter, LocalCachedPartitionedView, OpenTsdbWriter, TransactionalCachedView, TransactionalOnlineAttributeWriter

@Stable
public interface OnlineAttributeWriter
extends AttributeWriterBase

Writer for attribute values. This is online version, where each element is committed one after another.

The ingest process works as follows:

• incoming request is written into CommitLog, which is instance of this interface
• the message is confirmed to the client, because commit log is persistent, durable and distributed
• next, the message is asynchronously consumed by all writes from the commit log and written to the storages

Note that as a commit log might be marked any "regular" storage of the message. If so, the message is not written to the commit log twice.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	OnlineAttributeWriter.Factory<T extends OnlineAttributeWriter>	Serializable factory for OnlineAttributeWriter.

Nested classes/interfaces inherited from interface cz.o2.proxima.direct.core.AttributeWriterBase

AttributeWriterBase.Type

Method Summary

Modifier and Type	Method	Description
OnlineAttributeWriter.Factory<? extends OnlineAttributeWriter>	asFactory()	Convert instance of this writer to AttributeWriterBase.Factory suitable for serialization.
default AttributeWriterBase.Type	getType()	Retrieve type of the writer.
default boolean	isTransactional()
default void	rollback()	Rollback the writer to last committed position.
default TransactionalOnlineAttributeWriter	transactional()
void	write(StreamElement data, CommitCallback statusCallback)	Write given serialized attribute value to given entity.

Methods inherited from interface cz.o2.proxima.direct.core.AttributeWriterBase

bulk, close, getUri, online

Method Detail

getType

default AttributeWriterBase.Type getType()

Description copied from interface: AttributeWriterBase

Retrieve type of the writer.

Specified by:

getType in interface AttributeWriterBase

Returns:

AttributeWriterBase.Type of the writer

rollback

default void rollback()

Description copied from interface: AttributeWriterBase

Rollback the writer to last committed position.

Specified by:

rollback in interface AttributeWriterBase

write

void write(StreamElement data,
           CommitCallback statusCallback)

Write given serialized attribute value to given entity.

Parameters:

data - the data to write

statusCallback - callback used to commit data processing

asFactory

OnlineAttributeWriter.Factory<? extends OnlineAttributeWriter> asFactory()

Description copied from interface: AttributeWriterBase

Convert instance of this writer to AttributeWriterBase.Factory suitable for serialization.

Specified by:

asFactory in interface AttributeWriterBase

Returns:

the AttributeWriterBase.Factory representing this reader

isTransactional

default boolean isTransactional()

Returns:

true is this is a TransactionalOnlineAttributeWriter. TransactionalOnlineAttributeWriter is used when writing attribute that supports TransactionMode different from TransactionMode.NONE.

transactional

default TransactionalOnlineAttributeWriter transactional()

Returns:

this if isTransactional() returns true.

Throws:

java.lang.UnsupportedOperationException - if isTransactional() returns false