com.amazon.carbonado.spi

Class BelatedStorageCreator<S extends Storable>

java.lang.Object

com.amazon.carbonado.util.BelatedCreator<Storage<S>,SupportException>

com.amazon.carbonado.spi.BelatedStorageCreator<S>

public class BelatedStorageCreator<S extends Storable>
extends BelatedCreator<Storage<S>,SupportException>

Generic one-shot Storage creator which supports late object creation. If getting the Storage results in an exception or is taking too long, the Storage produced instead is a bogus one. Many operations result in an IllegalStateException. After retrying, if the real Storage is accessed, then the bogus Storage turns into a wrapper to the real Storage.

Author:

Brian S O'Neill

See Also:

BelatedRepositoryCreator

Constructor Summary

Constructors

Constructor and Description
BelatedStorageCreator(org.apache.commons.logging.Log log, Repository repo, java.lang.Class<S> storableType, int minRetryDelayMillis)

Method Summary

Methods

Modifier and Type	Method and Description
protected Storage<S>	createBogus() Create instance of bogus object.
protected Storage<S>	createReal() Create instance of real object.
protected void	timedOutNotification(long timedOutMillis) Notification that createReal is taking too long.

Methods inherited from class com.amazon.carbonado.util.BelatedCreator

createdNotification, get

Methods inherited from class java.lang.Object

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

Constructor Detail

BelatedStorageCreator

public BelatedStorageCreator(org.apache.commons.logging.Log log,
                     Repository repo,
                     java.lang.Class<S> storableType,
                     int minRetryDelayMillis)

Parameters:

log - error reporting log

repo - Repository to get Storage from

storableType - type of Storable to get Storage for

minRetryDelayMillis - minimum milliseconds to wait before retrying to create object after failure; if negative, never retry

Method Detail

createReal

protected Storage<S> createReal()
                                          throws SupportException

Description copied from class: BelatedCreator

Create instance of real object. If there is a recoverable error creating the object, return null. Any error logging must be performed by the implementation of this method. If null is returned, expect this method to be called again in the future.

Specified by:

createReal in class BelatedCreator<Storage<S extends Storable>,SupportException>

Returns:

real object, or null if there was a recoverable error

Throws:

SupportException

createBogus

protected Storage<S> createBogus()

Description copied from class: BelatedCreator

Create instance of bogus object.

Specified by:

createBogus in class BelatedCreator<Storage<S extends Storable>,SupportException>

timedOutNotification

protected void timedOutNotification(long timedOutMillis)

Description copied from class: BelatedCreator

Notification that createReal is taking too long. This can be used to log a message.

Specified by:

timedOutNotification in class BelatedCreator<Storage<S extends Storable>,SupportException>

Parameters:

timedOutMillis - milliseconds waited before giving up