net.openhft.chronicle.wire

Interface MessageHistory

All Superinterfaces:

net.openhft.chronicle.bytes.CommonMarshallable, Marshallable, ReadMarshallable, net.openhft.chronicle.core.io.Resettable, WriteMarshallable, WriteValue

All Known Implementing Classes:

VanillaMessageHistory

public interface MessageHistory
extends Marshallable

Records the path a message takes as it moves through components. Each processing step may append its source identifier and timestamp, allowing tracing and latency analysis in distributed systems.

Field Summary

Fields inherited from interface net.openhft.chronicle.wire.WriteMarshallable

EMPTY

Fields inherited from interface net.openhft.chronicle.wire.ReadMarshallable

DISCARD

Method Summary

Modifier and Type	Method and Description
static void	clear() Effectively calls set(null) removing the current thread-local history.
default void	doWriteHistory(DocumentContext dc) Default implementation for recording history into the supplied DocumentContext.
static void	emptyHistory() Sets the current thread-local history to a new empty VanillaMessageHistory.
static MessageHistory	get() Retrieves the thread-local MessageHistory instance for the message being processed.
boolean	isDirty()
int	lastSourceId() Returns the last source id contained in this MessageHistory.
long	lastSourceIndex() Returns the last source index contained in this MessageHistory.
void	reset() Clears all recorded source and timing entries.
void	reset(int sourceId, long sourceIndex) Resets the MessageHistory with the provided sourceId and sourceIndex as a starting point.
static void	set(MessageHistory md) You only need to call this if you wish to override its behaviour.
int	sourceId(int n) Returns the source id at a position specified by the input n.
boolean	sourceIdsEndsWith(int[] sourceIds) Returns true if the source ids contained in this MessageHistory end with the provided sourceIds.
long	sourceIndex(int n) Returns the index of the source at a position specified by the input n.
int	sources() Returns the number of sources contained in this MessageHistory.
long	timing(int n) Returns a timing at a position specified by the input n.
int	timings() Returns the number of timings contained in this MessageHistory.
static void	writeHistory(DocumentContext dc) Writes the current thread's history to the given document if the document is empty.

Methods inherited from interface net.openhft.chronicle.wire.Marshallable

$equals, $fieldInfoMap, $fieldInfos, $hashCode, $toString, className, copyTo, deepCopy, fromFile, fromFile, fromString, fromString, fromString, getField, getLongField, mergeToMap, readMarshallable, setField, setLongField, streamFromFile, streamFromFile, writeMarshallable

Methods inherited from interface net.openhft.chronicle.wire.WriteMarshallable

binaryLengthLength, writeValue

Methods inherited from interface net.openhft.chronicle.wire.ReadMarshallable

unexpectedField

Methods inherited from interface net.openhft.chronicle.bytes.CommonMarshallable

usesSelfDescribingMessage

Method Detail

get

static MessageHistory get()

Retrieves the thread-local MessageHistory instance for the message being processed.

Returns:

the history associated with the current excerpt.

set

static void set(MessageHistory md)

You only need to call this if you wish to override its behaviour.

Parameters:

md - to change to the default implementation for this thread. Null to clear the thread local and force withInitial to be called again

clear

static void clear()

Effectively calls set(null) removing the current thread-local history.

emptyHistory

static void emptyHistory()

Sets the current thread-local history to a new empty VanillaMessageHistory.

writeHistory

@UsedViaReflection
static void writeHistory(DocumentContext dc)

Writes the current thread's history to the given document if the document is empty.

Parameters:

dc - the DocumentContext to write the history to

doWriteHistory

default void doWriteHistory(DocumentContext dc)

Default implementation for recording history into the supplied DocumentContext. It writes an event named MethodReader.HISTORY with this history as the value.

Parameters:

dc - the document to append the history to

timings

int timings()

Returns the number of timings contained in this MessageHistory.

Returns:

the number of timings contained in this MessageHistory.

timing

long timing(int n)

Returns a timing at a position specified by the input n.

Returns:

a timing at a position specified by the input n.

sources

int sources()

Returns the number of sources contained in this MessageHistory.

Returns:

the number of sources contained in this MessageHistory.

sourceId

int sourceId(int n)

Returns the source id at a position specified by the input n.

Returns:

the source id at a position specified by the input n.

sourceIdsEndsWith

boolean sourceIdsEndsWith(int[] sourceIds)

Returns true if the source ids contained in this MessageHistory end with the provided sourceIds.

Returns:

true if the source ids contained in this MessageHistory end with the provided sourceIds.

sourceIndex

long sourceIndex(int n)

Returns the index of the source at a position specified by the input n.

Returns:

the index of the source at a position specified by the input n.

reset

void reset()

Clears all recorded source and timing entries.

Specified by:

reset in interface Marshallable

Specified by:

reset in interface net.openhft.chronicle.core.io.Resettable

reset

void reset(int sourceId,
           long sourceIndex)

Resets the MessageHistory with the provided sourceId and sourceIndex as a starting point.

lastSourceId

int lastSourceId()

Returns the last source id contained in this MessageHistory.

Returns:

the last source id contained in this MessageHistory.

lastSourceIndex

long lastSourceIndex()

Returns the last source index contained in this MessageHistory.

Returns:

the last source index contained in this MessageHistory.

isDirty

boolean isDirty()

Returns:

true if the message history has not been written using Marshallable.writeMarshallable(net.openhft.chronicle.wire.WireOut)