Package ch.qos.logback.core

Class AsyncAppenderBase<E>

java.lang.Object
ch.qos.logback.core.spi.ContextAwareBase
ch.qos.logback.core.UnsynchronizedAppenderBase<E>
ch.qos.logback.core.AsyncAppenderBase<E>
Type Parameters:
E -
All Implemented Interfaces:
Appender<E>, AppenderAttachable<E>, ContextAware, FilterAttachable<E>, LifeCycle
public class AsyncAppenderBase<E> extends UnsynchronizedAppenderBase<E> implements AppenderAttachable<E>
This appender and derived classes, log events asynchronously. In order to avoid loss of logging events, this appender should be closed. It is the user's responsibility to close appenders, typically at the end of the application lifecycle.

This appender buffers events in a BlockingQueue. AsyncAppenderBase.Worker thread created by this appender takes events from the head of the queue, and dispatches them to the single appender attached to this appender.

Please refer to the logback manual for further information about this appender.

Since:
1.0.4
Author:
Ceki Gülcü, Torsten Juergeleit

  • Field Details

    • DEFAULT_QUEUE_SIZE

      public static final int DEFAULT_QUEUE_SIZE
      The default buffer size.
      See Also:
      Constant Field Values

    • DEFAULT_MAX_FLUSH_TIME

      public static final int DEFAULT_MAX_FLUSH_TIME
      The default maximum queue flush time allowed during appender stop. If the worker takes longer than this time it will exit, discarding any remaining items in the queue
      See Also:
      Constant Field Values

  • Constructor Details

    • AsyncAppenderBase

      public AsyncAppenderBase()

  • Method Details

    • isDiscardable

      protected boolean isDiscardable​(E eventObject)
      Is the eventObject passed as parameter discardable? The base class's implementation of this method always returns 'false' but sub-classes may (and do) override this method.

      Note that only if the buffer is nearly full are events discarded. Otherwise, when the buffer is "not full" all events are logged.

      Parameters:
      eventObject -
      Returns:
      - true if the event can be discarded, false otherwise

    • preprocess

      protected void preprocess​(E eventObject)
      Pre-process the event prior to queueing. The base class does no pre-processing but sub-classes can override this behavior.
      Parameters:
      eventObject -

    • start

      public void start()
      Specified by:
      start in interface LifeCycle
      Overrides:
      start in class UnsynchronizedAppenderBase<E>

    • stop

      public void stop()
      Specified by:
      stop in interface LifeCycle
      Overrides:
      stop in class UnsynchronizedAppenderBase<E>

    • append

      protected void append​(E eventObject)
      Specified by:
      append in class UnsynchronizedAppenderBase<E>

    • getQueueSize

      public int getQueueSize()

    • setQueueSize

      public void setQueueSize​(int queueSize)

    • getDiscardingThreshold

      public int getDiscardingThreshold()

    • setDiscardingThreshold

      public void setDiscardingThreshold​(int discardingThreshold)

    • getMaxFlushTime

      public int getMaxFlushTime()

    • setMaxFlushTime

      public void setMaxFlushTime​(int maxFlushTime)

    • getNumberOfElementsInQueue

      public int getNumberOfElementsInQueue()
      Returns the number of elements currently in the blocking queue.
      Returns:
      number of elements currently in the queue.

    • setNeverBlock

      public void setNeverBlock​(boolean neverBlock)

    • isNeverBlock

      public boolean isNeverBlock()

    • getRemainingCapacity

      public int getRemainingCapacity()
      The remaining capacity available in the blocking queue.

      See also BlockingQueue#remainingCapacity()

      Returns:
      the remaining capacity

    • addAppender

      public void addAppender​(Appender<E> newAppender)
      Description copied from interface: AppenderAttachable
      Add an appender.
      Specified by:
      addAppender in interface AppenderAttachable<E>

    • iteratorForAppenders

      public Iterator<Appender<E>> iteratorForAppenders()
      Description copied from interface: AppenderAttachable
      Get an iterator for appenders contained in the parent object.
      Specified by:
      iteratorForAppenders in interface AppenderAttachable<E>

    • getAppender

      public Appender<E> getAppender​(String name)
      Description copied from interface: AppenderAttachable
      Get an appender by name.
      Specified by:
      getAppender in interface AppenderAttachable<E>

    • isAttached

      public boolean isAttached​(Appender<E> eAppender)
      Description copied from interface: AppenderAttachable
      Returns true if the specified appender is in list of attached attached, false otherwise.
      Specified by:
      isAttached in interface AppenderAttachable<E>

    • detachAndStopAllAppenders

      public void detachAndStopAllAppenders()
      Description copied from interface: AppenderAttachable
      Detach and processPriorToRemoval all previously added appenders.
      Specified by:
      detachAndStopAllAppenders in interface AppenderAttachable<E>

    • detachAppender

      public boolean detachAppender​(Appender<E> eAppender)
      Description copied from interface: AppenderAttachable
      Detach the appender passed as parameter from the list of appenders.
      Specified by:
      detachAppender in interface AppenderAttachable<E>

    • detachAppender

      public boolean detachAppender​(String name)
      Description copied from interface: AppenderAttachable
      Detach the appender with the name passed as parameter from the list of appenders.
      Specified by:
      detachAppender in interface AppenderAttachable<E>