io.zeebe.logstreams.impl.snapshot.fs

Class FsSnapshotWriter

java.lang.Object

io.zeebe.logstreams.impl.snapshot.fs.FsSnapshotWriter

All Implemented Interfaces:

SnapshotWriter

Direct Known Subclasses:

FsTemporarySnapshotWriter

public class FsSnapshotWriter
extends Object
implements SnapshotWriter

Field Summary

Fields

Modifier and Type	Field and Description
protected File	checksumFile
protected FsSnapshotStorageConfiguration	config
protected File	dataFile
protected DigestOutputStream	dataOutputStream
protected FsReadableSnapshot	lastSnapshot
static org.slf4j.Logger	LOG

Constructor Summary

Constructors

Constructor and Description
FsSnapshotWriter(FsSnapshotStorageConfiguration config, File snapshotFile, File checksumFile, FsReadableSnapshot lastSnapshot)

Method Summary

Modifier and Type	Method and Description
void	abort() Refuse the snapshot by closing the output stream and deleting the snapshot data.
void	commit() Completes the snapshot by closing the output stream and writing the checksum.
protected void	commit(byte[] checksum)
protected void	deleteLastSnapshot()
File	getChecksumFile()
File	getDataFile()
protected String	getDataFileName()
OutputStream	getOutputStream() Returns the output stream of the snapshot which should be used to write the snapshot data.
protected void	initOutputStreams(FsSnapshotStorageConfiguration config, File snapshotFile)
void	validateAndCommit(byte[] checksum) Completes the snapshot by closing the output stream and writing its checksum, iff the checksum is equal to the given checksum.
protected void	writeChecksumFile(byte[] checksum)

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.zeebe.logstreams.spi.SnapshotWriter

writeSnapshot

Field Detail

LOG

public static final org.slf4j.Logger LOG

config

protected final FsSnapshotStorageConfiguration config

dataFile

protected final File dataFile

checksumFile

protected final File checksumFile

lastSnapshot

protected final FsReadableSnapshot lastSnapshot

dataOutputStream

protected DigestOutputStream dataOutputStream

Constructor Detail

FsSnapshotWriter

public FsSnapshotWriter(FsSnapshotStorageConfiguration config,
                        File snapshotFile,
                        File checksumFile,
                        FsReadableSnapshot lastSnapshot)

Method Detail

initOutputStreams

protected void initOutputStreams(FsSnapshotStorageConfiguration config,
                                 File snapshotFile)

getOutputStream

public OutputStream getOutputStream()

Description copied from interface: SnapshotWriter

Returns the output stream of the snapshot which should be used to write the snapshot data. Finish the write operation with SnapshotWriter.commit() or SnapshotWriter.abort().

Specified by:

getOutputStream in interface SnapshotWriter

Returns:

the snapshot output stream

commit

public void commit()
            throws Exception

Description copied from interface: SnapshotWriter

Completes the snapshot by closing the output stream and writing the checksum.

Specified by:

commit in interface SnapshotWriter

Throws:

Exception - if fails to write the checksum

validateAndCommit

public void validateAndCommit(byte[] checksum)
                       throws Exception

Description copied from interface: SnapshotWriter

Completes the snapshot by closing the output stream and writing its checksum, iff the checksum is equal to the given checksum.

It will call abort on exception, or if the checksums do not match.

Specified by:

validateAndCommit in interface SnapshotWriter

Parameters:

checksum - checksum to check against

Throws:

Exception

abort

public void abort()

Description copied from interface: SnapshotWriter

Refuse the snapshot by closing the output stream and deleting the snapshot data.

Specified by:

abort in interface SnapshotWriter

getChecksumFile

public File getChecksumFile()

getDataFile

public File getDataFile()

getDataFileName

protected String getDataFileName()

commit

protected void commit(byte[] checksum)
               throws Exception

Throws:

Exception

writeChecksumFile

protected void writeChecksumFile(byte[] checksum)
                          throws Exception

Throws:

Exception

deleteLastSnapshot

protected void deleteLastSnapshot()