org.apache.mesos
Class Log.Writer

java.lang.Object
  org.apache.mesos.Log.Writer

Enclosing class:

Log

public static class Log.Writer
extends Object

Provides write access to the Log. This class is not safe for use from multiple threads and instances should be thrown out after any Log.WriterFailedException is thrown.

Constructor Summary

Log.Writer(Log log, long timeout, TimeUnit unit, int retries)

Method Summary

Log.Position	append(byte[] data, long timeout, TimeUnit unit) Attempts to append to the log with the specified data returning the new end position of the log if successful.
protected void	finalize()
protected void	initialize(Log log, long timeout, TimeUnit unit, int retries)
Log.Position	truncate(Log.Position to, long timeout, TimeUnit unit) Attempts to truncate the log (from the beginning to the specified position exclusive) If the position is invalid, an WriterFailedException will get thrown.

Methods inherited from class java.lang.Object

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

Constructor Detail

Log.Writer

public Log.Writer(Log log,
                  long timeout,
                  TimeUnit unit,
                  int retries)

Method Detail

append

public Log.Position append(byte[] data,
                           long timeout,
                           TimeUnit unit)
                    throws TimeoutException,
                           Log.WriterFailedException

Attempts to append to the log with the specified data returning the new end position of the log if successful.

Throws:

TimeoutException

Log.WriterFailedException

truncate

public Log.Position truncate(Log.Position to,
                             long timeout,
                             TimeUnit unit)
                      throws TimeoutException,
                             Log.WriterFailedException

Attempts to truncate the log (from the beginning to the specified position exclusive) If the position is invalid, an WriterFailedException will get thrown. Unfortunately, this will also get thrown in other circumstances (e.g., disk failure) and therefore it is currently impossible to tell these two cases apart.

TODO(benh): Throw both OperationFailedException and WriterFailedException to differentiate the need for a new writer from a bad position, or a bad disk, etc.

Throws:

TimeoutException

Log.WriterFailedException

initialize

protected void initialize(Log log,
                          long timeout,
                          TimeUnit unit,
                          int retries)

finalize

protected void finalize()

Overrides:

finalize in class Object