com.kdgregory.logging.common

Interface LogWriter

All Superinterfaces:

Runnable

All Known Implementing Classes:

AbstractLogWriter, CloudWatchLogWriter, KinesisLogWriter, SNSLogWriter

public interface LogWriter
extends Runnable

Defines the contract between appenders and writers.

Writers normally run on a background thread, gathering messages into batches and sending them based on a time delay. Writers can also operate in "synchronous" mode, in which batch building/sending is triggered by the appender.

Method Summary

Modifier and Type	Method and Description
void	addMessage(LogMessage message) Adds a message to the writer's message queue.
boolean	isSynchronous() Returns a flag to indicate whether the writer is operating in synchrnous mode.
int	maxMessageSize() Returns the maximum allowed UTF-8 message size for the destination.
void	setBatchDelay(long value) Sets the batch delay for the writer.
void	setDiscardAction(MessageQueue.DiscardAction value) Updates the writer's discard action: how it discards messages once the threshold has been reached.
void	setDiscardThreshold(int value) Updates the writer's discard threshold: the maximum number of message stored in its queue.
void	stop() Signals the writer that it will no longer receive batches.
boolean	waitUntilInitialized(long millisToWait) Waits up to the specified amount of time for the writer to initialize.
void	waitUntilStopped(long millisToWait) Waits until the writer thread has stopped, the timeout has expired, or the calling thread is interrupted.

Methods inherited from interface java.lang.Runnable

run

Method Detail

setBatchDelay

void setBatchDelay(long value)

Sets the batch delay for the writer. The appender is assumed to expose a delay parameter, and this method allows it to change the writer's delay at runtime. Changes may or may not take place immediately.

This is a no-op if the writer doesn't support batching or is in synchronous mode.

setDiscardThreshold

void setDiscardThreshold(int value)

Updates the writer's discard threshold: the maximum number of message stored in its queue.

setDiscardAction

void setDiscardAction(MessageQueue.DiscardAction value)

Updates the writer's discard action: how it discards messages once the threshold has been reached.

isSynchronous

boolean isSynchronous()

Returns a flag to indicate whether the writer is operating in synchrnous mode.

maxMessageSize

int maxMessageSize()

Returns the maximum allowed UTF-8 message size for the destination.

waitUntilInitialized

boolean waitUntilInitialized(long millisToWait)

Waits up to the specified amount of time for the writer to initialize.

Returns:

true if it initialized successfully, false if writer failed to initialize, the timeout expired, or the calling thread was interrupted.

addMessage

void addMessage(LogMessage message)

Adds a message to the writer's message queue. If in synchronous mode, this also triggers batch processing.

Implementations should assume that they are invoked within a synchronized block, and therefore should not perform excessive amounts work (synchronous mode being an exception).

stop

void stop()

Signals the writer that it will no longer receive batches. It should, however, make a best effort to send any batches that it already has before exiting its run() method.

waitUntilStopped

void waitUntilStopped(long millisToWait)

Waits until the writer thread has stopped, the timeout has expired, or the calling thread is interrupted.