org.apache.zookeeper.server.persistence

Class SnapStream

java.lang.Object

org.apache.zookeeper.server.persistence.SnapStream

public class SnapStream
extends Object

Represent the Stream used in serialize and deserialize the Snapshot.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	SnapStream.StreamMode

Field Summary

Fields

Modifier and Type	Field and Description
static String	ZOOKEEPER_SHAPSHOT_STREAM_MODE

Constructor Summary

Constructors

Constructor and Description
SnapStream()

Method Summary

Modifier and Type	Method and Description
static CheckedInputStream	getInputStream(File file) Return the CheckedInputStream based on the extension of the fileName.
static CheckedOutputStream	getOutputStream(File file, boolean fsync) Return the OutputStream based on predefined stream mode.
static SnapStream.StreamMode	getStreamMode()
static SnapStream.StreamMode	getStreamMode(String fileName) Detect the stream mode from file name extension
static boolean	isValidSnapshot(File file) Verifies that the file is a valid snapshot.
static void	sealStream(CheckedOutputStream os, OutputArchive oa) Write specific seal to the OutputArchive and close the OutputStream.
static void	setStreamMode(SnapStream.StreamMode mode)

Methods inherited from class java.lang.Object

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

Field Detail

ZOOKEEPER_SHAPSHOT_STREAM_MODE

public static final String ZOOKEEPER_SHAPSHOT_STREAM_MODE

See Also:

Constant Field Values

Constructor Detail

SnapStream

public SnapStream()

Method Detail

getInputStream

public static CheckedInputStream getInputStream(File file)
                                         throws IOException

Return the CheckedInputStream based on the extension of the fileName.

Parameters:

file - the file the InputStream read from

Returns:

the specific InputStream

Throws:

IOException

getOutputStream

public static CheckedOutputStream getOutputStream(File file,
                                                  boolean fsync)
                                           throws IOException

Return the OutputStream based on predefined stream mode.

Parameters:

file - the file the OutputStream writes to

fsync - sync the file immediately after write

Returns:

the specific OutputStream

Throws:

IOException

sealStream

public static void sealStream(CheckedOutputStream os,
                              OutputArchive oa)
                       throws IOException

Write specific seal to the OutputArchive and close the OutputStream. Currently, only CheckedOutputStream will write it's checkSum to the end of the stream.

Throws:

IOException

isValidSnapshot

public static boolean isValidSnapshot(File file)
                               throws IOException

Verifies that the file is a valid snapshot. Snapshot may be invalid if it's incomplete as in a situation when the server dies while in the process of storing a snapshot. Any files that are improperly formated or corrupted are invalid. Any file that is not a snapshot is also an invalid snapshot.

Parameters:

file - file to verify

Returns:

true if the snapshot is valid

Throws:

IOException

setStreamMode

public static void setStreamMode(SnapStream.StreamMode mode)

getStreamMode

public static SnapStream.StreamMode getStreamMode()

getStreamMode

public static SnapStream.StreamMode getStreamMode(String fileName)

Detect the stream mode from file name extension

Parameters:

fileName -

Returns:

the stream mode detected