org.apache.seatunnel.api.sink

接口 SinkWriter<T,CommitInfoT,StateT>

类型参数:

T - The data class by sink accept. Only support SeaTunnelRow at now.

CommitInfoT - The type of commit message.

StateT - The type of state.

public interface SinkWriter<T,CommitInfoT,StateT>

The sink writer use to write data to third party data receiver. This class will run on taskManger/Worker.

嵌套类概要

嵌套类

限定符和类型	接口和说明
static interface	SinkWriter.Context

方法概要

限定符和类型	方法和说明
void	abortPrepare() Used to abort the prepareCommit(), if the prepareCommit failed, there is no CommitInfoT, so the rollback work cannot be done by SinkCommitter.
default void	applySchemaChange(SchemaChangeEvent event) apply schema change to third party data receiver.
void	close() call it when SinkWriter close
Optional<CommitInfoT>	prepareCommit() prepare the commit, will be called before snapshotState(long checkpointId).
default List<StateT>	snapshotState(long checkpointId)
void	write(T element) write data to third party data receiver.

方法详细资料

write

void write(T element)
    throws IOException

write data to third party data receiver.

参数:

element - the data need be written.

抛出:

IOException - throw IOException when write data failed.

applySchemaChange

default void applySchemaChange(SchemaChangeEvent event)
                        throws IOException

apply schema change to third party data receiver.

参数:

event -

抛出:

IOException

prepareCommit

Optional<CommitInfoT> prepareCommit()
                             throws IOException

prepare the commit, will be called before snapshotState(long checkpointId). If you need to use 2pc, you can return the commit info in this method, and receive the commit info in SinkCommitter.commit(List). If this method failed (by throw exception), **Only** Spark engine will call abortPrepare()

返回:

the commit info need to commit

抛出:

IOException

snapshotState

default List<StateT> snapshotState(long checkpointId)
                            throws IOException

返回:

The writer's state.

抛出:

IOException - if fail to snapshot writer's state.

abortPrepare

void abortPrepare()

Used to abort the prepareCommit(), if the prepareCommit failed, there is no CommitInfoT, so the rollback work cannot be done by SinkCommitter. But we can use this method to rollback side effects of prepareCommit(). Only use it in Spark engine at now.

close

void close()
    throws IOException

call it when SinkWriter close

抛出:

IOException - if close failed