org.agrona

Class MarkFile

java.lang.Object

org.agrona.MarkFile

All Implemented Interfaces:

java.lang.AutoCloseable

public class MarkFile
extends java.lang.Object
implements java.lang.AutoCloseable

A MarkFile is used to mark the presence of a running component and to track liveness. The assumptions are: (1) the version field is an int in size, (2) the timestamp field is a long in size, and (3) the version field comes before the timestamp field.

Constructor Summary

Constructors

Constructor and Description
MarkFile(java.io.File markFile, boolean shouldPreExist, int versionFieldOffset, int timestampFieldOffset, int totalFileLength, long timeoutMs, EpochClock epochClock, java.util.function.IntConsumer versionCheck, java.util.function.Consumer<java.lang.String> logger) Create a MarkFile if none present.
MarkFile(java.io.File directory, java.lang.String filename, boolean warnIfDirectoryExists, boolean dirDeleteOnStart, int versionFieldOffset, int timestampFieldOffset, int totalFileLength, long timeoutMs, EpochClock epochClock, java.util.function.IntConsumer versionCheck, java.util.function.Consumer<java.lang.String> logger) Create a directory and mark file if none present.
MarkFile(java.io.File directory, java.lang.String filename, int versionFieldOffset, int timestampFieldOffset, long timeoutMs, EpochClock epochClock, java.util.function.IntConsumer versionCheck, java.util.function.Consumer<java.lang.String> logger) Map a pre-existing MarkFile if one present and is active.
MarkFile(java.nio.MappedByteBuffer mappedBuffer, int versionFieldOffset, int timestampFieldOffset) Manage a MarkFile given a mapped file and offsets of version and timestamp.
MarkFile(UnsafeBuffer buffer, int versionFieldOffset, int timestampFieldOffset) Manage a MarkFile given a buffer and offsets of version and timestamp.

Method Summary

Modifier and Type	Method and Description
UnsafeBuffer	buffer()
void	close()
void	deleteDirectory(boolean ignoreFailures)
static void	ensureDirectoryExists(java.io.File directory, java.lang.String filename, boolean warnIfDirectoryExists, boolean dirDeleteOnStart, int versionFieldOffset, int timestampFieldOffset, long timeoutMs, EpochClock epochClock, java.util.function.IntConsumer versionCheck, java.util.function.Consumer<java.lang.String> logger)
static boolean	isActive(java.nio.MappedByteBuffer byteBuffer, EpochClock epochClock, long timeoutMs, int versionFieldOffset, int timestampFieldOffset, java.util.function.IntConsumer versionCheck, java.util.function.Consumer<java.lang.String> logger)
boolean	isClosed()
static java.nio.MappedByteBuffer	mapExistingFile(java.io.File markFile, java.util.function.Consumer<java.lang.String> logger, long offset, long length)
static java.nio.MappedByteBuffer	mapExistingMarkFile(java.io.File markFile, int versionFieldOffset, int timestampFieldOffset, long timeoutMs, EpochClock epochClock, java.util.function.IntConsumer versionCheck, java.util.function.Consumer<java.lang.String> logger)
static java.nio.MappedByteBuffer	mapNewOrExistingMarkFile(java.io.File markFile, boolean shouldPreExist, int versionFieldOffset, int timestampFieldOffset, long totalFileLength, long timeoutMs, EpochClock epochClock, java.util.function.IntConsumer versionCheck, java.util.function.Consumer<java.lang.String> logger)
java.nio.MappedByteBuffer	mappedByteBuffer()
java.io.File	markFile()
java.io.File	parentDirectory()
void	signalReady(int version)
void	timestampOrdered(long timestamp)
long	timestampVolatile()
long	timestampWeak()
int	versionVolatile()
int	versionWeak()
static java.nio.MappedByteBuffer	waitForFileMapping(java.util.function.Consumer<java.lang.String> logger, java.io.File markFile, long deadlineMs, EpochClock epochClock)

Methods inherited from class java.lang.Object

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

Constructor Detail

MarkFile

public MarkFile(java.io.File directory,
                java.lang.String filename,
                boolean warnIfDirectoryExists,
                boolean dirDeleteOnStart,
                int versionFieldOffset,
                int timestampFieldOffset,
                int totalFileLength,
                long timeoutMs,
                EpochClock epochClock,
                java.util.function.IntConsumer versionCheck,
                java.util.function.Consumer<java.lang.String> logger)

Create a directory and mark file if none present. Checking if an active Mark file exists and is active. Old Mark file is deleted and recreated if not active. Total length of Mark file will be mapped until close() is called.

Parameters:

directory - for the Mark file

filename - of the Mark file

warnIfDirectoryExists - for logging purposes

dirDeleteOnStart - if desired

versionFieldOffset - to use for version field access

timestampFieldOffset - to use for timestamp field access

totalFileLength - to allocate when creating new Mark file

timeoutMs - for the activity check (in milliseconds)

epochClock - to use for time checks

versionCheck - to use for existing Mark file and version field

logger - to use to signal progress or null

MarkFile

public MarkFile(java.io.File markFile,
                boolean shouldPreExist,
                int versionFieldOffset,
                int timestampFieldOffset,
                int totalFileLength,
                long timeoutMs,
                EpochClock epochClock,
                java.util.function.IntConsumer versionCheck,
                java.util.function.Consumer<java.lang.String> logger)

Create a MarkFile if none present. Checking if an active MarkFile exists and is active. Existing MarkFile is used if not active. Total length of Mark file will be mapped until close() is called.

Parameters:

markFile - to use

shouldPreExist - or not

versionFieldOffset - to use for version field access

timestampFieldOffset - to use for timestamp field access

totalFileLength - to allocate when creating new MarkFile

timeoutMs - for the activity check (in milliseconds)

epochClock - to use for time checks

versionCheck - to use for existing MarkFile and version field

logger - to use to signal progress or null

MarkFile

public MarkFile(java.io.File directory,
                java.lang.String filename,
                int versionFieldOffset,
                int timestampFieldOffset,
                long timeoutMs,
                EpochClock epochClock,
                java.util.function.IntConsumer versionCheck,
                java.util.function.Consumer<java.lang.String> logger)

Map a pre-existing MarkFile if one present and is active. Total length of MarkFile will be mapped until close() is called.

Parameters:

directory - for the MarkFile file

filename - of the MarkFile file

versionFieldOffset - to use for version field access

timestampFieldOffset - to use for timestamp field access

timeoutMs - for the activity check (in milliseconds) and for how long to wait for file to exist

epochClock - to use for time checks

versionCheck - to use for existing MarkFile file and version field

logger - to use to signal progress or null

MarkFile

public MarkFile(java.nio.MappedByteBuffer mappedBuffer,
                int versionFieldOffset,
                int timestampFieldOffset)

Manage a MarkFile given a mapped file and offsets of version and timestamp. If mappedBuffer is not null, then it will be unmapped upon close().

Parameters:

mappedBuffer - for the MarkFile fields

versionFieldOffset - for the version field

timestampFieldOffset - for the timestamp field

MarkFile

public MarkFile(UnsafeBuffer buffer,
                int versionFieldOffset,
                int timestampFieldOffset)

Manage a MarkFile given a buffer and offsets of version and timestamp.

Parameters:

buffer - for the MarkFile fields

versionFieldOffset - for the version field

timestampFieldOffset - for the timestamp field

Method Detail

isClosed

public boolean isClosed()

close

public void close()

Specified by:

close in interface java.lang.AutoCloseable

signalReady

public void signalReady(int version)

versionVolatile

public int versionVolatile()

versionWeak

public int versionWeak()

timestampOrdered

public void timestampOrdered(long timestamp)

timestampVolatile

public long timestampVolatile()

timestampWeak

public long timestampWeak()

deleteDirectory

public void deleteDirectory(boolean ignoreFailures)

parentDirectory

public java.io.File parentDirectory()

markFile

public java.io.File markFile()

mappedByteBuffer

public java.nio.MappedByteBuffer mappedByteBuffer()

buffer

public UnsafeBuffer buffer()

ensureDirectoryExists

public static void ensureDirectoryExists(java.io.File directory,
                                         java.lang.String filename,
                                         boolean warnIfDirectoryExists,
                                         boolean dirDeleteOnStart,
                                         int versionFieldOffset,
                                         int timestampFieldOffset,
                                         long timeoutMs,
                                         EpochClock epochClock,
                                         java.util.function.IntConsumer versionCheck,
                                         java.util.function.Consumer<java.lang.String> logger)

waitForFileMapping

public static java.nio.MappedByteBuffer waitForFileMapping(java.util.function.Consumer<java.lang.String> logger,
                                                           java.io.File markFile,
                                                           long deadlineMs,
                                                           EpochClock epochClock)

mapExistingMarkFile

public static java.nio.MappedByteBuffer mapExistingMarkFile(java.io.File markFile,
                                                            int versionFieldOffset,
                                                            int timestampFieldOffset,
                                                            long timeoutMs,
                                                            EpochClock epochClock,
                                                            java.util.function.IntConsumer versionCheck,
                                                            java.util.function.Consumer<java.lang.String> logger)

mapNewOrExistingMarkFile

public static java.nio.MappedByteBuffer mapNewOrExistingMarkFile(java.io.File markFile,
                                                                 boolean shouldPreExist,
                                                                 int versionFieldOffset,
                                                                 int timestampFieldOffset,
                                                                 long totalFileLength,
                                                                 long timeoutMs,
                                                                 EpochClock epochClock,
                                                                 java.util.function.IntConsumer versionCheck,
                                                                 java.util.function.Consumer<java.lang.String> logger)

mapExistingFile

public static java.nio.MappedByteBuffer mapExistingFile(java.io.File markFile,
                                                        java.util.function.Consumer<java.lang.String> logger,
                                                        long offset,
                                                        long length)

isActive

public static boolean isActive(java.nio.MappedByteBuffer byteBuffer,
                               EpochClock epochClock,
                               long timeoutMs,
                               int versionFieldOffset,
                               int timestampFieldOffset,
                               java.util.function.IntConsumer versionCheck,
                               java.util.function.Consumer<java.lang.String> logger)