org.apache.flink.runtime.state

类 DuplicatingCheckpointOutputStream

java.lang.Object

java.io.OutputStream

org.apache.flink.core.fs.FSDataOutputStream

org.apache.flink.runtime.state.CheckpointStateOutputStream

org.apache.flink.runtime.state.DuplicatingCheckpointOutputStream

所有已实现的接口:

Closeable, Flushable, AutoCloseable

public class DuplicatingCheckpointOutputStream
extends CheckpointStateOutputStream

A CheckpointStateOutputStream that wraps a primary and a secondary CheckpointStateOutputStream and duplicates all writes into both streams. This stream applies buffering to reduce the amount of dual-method calling. Furthermore, exceptions that happen in interactions with the secondary stream are not exposed, until the user calls closeAndGetSecondaryHandle(). In contrast to that, exceptions from interactions with the primary stream are immediately returned to the user. This class is used to write state for local recovery as a local (secondary) copy of the (primary) state snapshot that is written to a (slower but highly-available) remote filesystem.

构造器概要

构造器

构造器和说明
DuplicatingCheckpointOutputStream(CheckpointStateOutputStream primaryOutputStream, CheckpointStateOutputStream secondaryOutputStream)
DuplicatingCheckpointOutputStream(CheckpointStateOutputStream primaryOutputStream, CheckpointStateOutputStream secondaryOutputStream, int bufferSize)

方法概要

限定符和类型	方法和说明
void	close() This method should close the stream, if has not been closed before.
StreamStateHandle	closeAndGetHandle() Closes the stream and gets a state handle that can create an input stream producing the data written to this stream.
StreamStateHandle	closeAndGetPrimaryHandle() Returns the state handle from the primaryOutputStream.
StreamStateHandle	closeAndGetSecondaryHandle() Returns the state handle from the secondaryOutputStream.
void	flush()
long	getPos()
Exception	getSecondaryStreamException()
void	sync()
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)

从类继承的方法 java.lang.Object

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

构造器详细资料

DuplicatingCheckpointOutputStream

public DuplicatingCheckpointOutputStream(CheckpointStateOutputStream primaryOutputStream,
                                         CheckpointStateOutputStream secondaryOutputStream)
                                  throws IOException

抛出:

IOException

DuplicatingCheckpointOutputStream

public DuplicatingCheckpointOutputStream(CheckpointStateOutputStream primaryOutputStream,
                                         CheckpointStateOutputStream secondaryOutputStream,
                                         int bufferSize)
                                  throws IOException

抛出:

IOException

方法详细资料

write

public void write(int b)
           throws IOException

指定者:

write 在类中 OutputStream

抛出:

IOException

write

public void write(byte[] b)
           throws IOException

覆盖:

write 在类中 OutputStream

抛出:

IOException

write

public void write(byte[] b,
                  int off,
                  int len)
           throws IOException

覆盖:

write 在类中 OutputStream

抛出:

IOException

getPos

public long getPos()
            throws IOException

指定者:

getPos 在类中 org.apache.flink.core.fs.FSDataOutputStream

抛出:

IOException

flush

public void flush()
           throws IOException

指定者:

flush 在接口中 Flushable

指定者:

flush 在类中 org.apache.flink.core.fs.FSDataOutputStream

抛出:

IOException

sync

public void sync()
          throws IOException

指定者:

sync 在类中 org.apache.flink.core.fs.FSDataOutputStream

抛出:

IOException

close

public void close()
           throws IOException

从类复制的说明: CheckpointStateOutputStream

This method should close the stream, if has not been closed before. If this method actually closes the stream, it should delete/release the resource behind the stream, such as the file that the stream writes to.

The above implies that this method is intended to be the "unsuccessful close", such as when cancelling the stream writing, or when an exception occurs. Closing the stream for the successful case must go through CheckpointStateOutputStream.closeAndGetHandle().

指定者:

close 在接口中 Closeable

指定者:

close 在接口中 AutoCloseable

指定者:

close 在类中 CheckpointStateOutputStream

抛出:

IOException - Thrown, if the stream cannot be closed.

closeAndGetHandle

@Nullable
public StreamStateHandle closeAndGetHandle()
                                              throws IOException

从类复制的说明: CheckpointStateOutputStream

Closes the stream and gets a state handle that can create an input stream producing the data written to this stream.

This closing must be called (also when the caller is not interested in the handle) to successfully close the stream and retain the produced resource. In contrast, the CheckpointStateOutputStream.close() method removes the target resource when called.

指定者:

closeAndGetHandle 在类中 CheckpointStateOutputStream

返回:

A state handle that can create an input stream producing the data written to this stream.

抛出:

IOException - Thrown, if the stream cannot be closed.

closeAndGetPrimaryHandle

public StreamStateHandle closeAndGetPrimaryHandle()
                                           throws IOException

Returns the state handle from the primaryOutputStream.

抛出:

IOException

closeAndGetSecondaryHandle

public StreamStateHandle closeAndGetSecondaryHandle()
                                             throws IOException

Returns the state handle from the secondaryOutputStream. Also reports suppressed exceptions from earlier interactions with that stream.

抛出:

IOException

getSecondaryStreamException

public Exception getSecondaryStreamException()