org.ehcache.impl.internal.loaderwriter.writebehind
Class StripedWriteBehind<K,V>

java.lang.Object
  org.ehcache.impl.internal.loaderwriter.writebehind.StripedWriteBehind<K,V>

All Implemented Interfaces:

WriteBehind<K,V>, CacheLoaderWriter<K,V>

public class StripedWriteBehind<K,V>
extends java.lang.Object
implements WriteBehind<K,V>

Constructor Summary

StripedWriteBehind(ExecutionService executionService, java.lang.String defaultThreadPool, WriteBehindConfiguration config, CacheLoaderWriter<K,V> cacheLoaderWriter)

Method Summary

void	delete(K key) Deletes a single entry from the underlying system of record.
void	deleteAll(java.lang.Iterable<? extends K> keys) Deletes a set of entry from the underlying system of record.
long	getQueueSize() Gets the best estimate for items in the queue still awaiting processing.
V	load(K key) Loads the value to be associated with the given key in the Cache using this CacheLoaderWriter instance.
java.util.Map<K,V>	loadAll(java.lang.Iterable<? extends K> keys) Loads the values to be associated with the keys in the Cache using this CacheLoaderWriter instance.
void	start() Start the write behind queue
void	stop() Stop the coordinator and all the internal data structures.
void	write(K key, V value) Writes a single entry to the underlying system of record, maybe a brand new value or an update to an existing value
void	writeAll(java.lang.Iterable<? extends java.util.Map.Entry<? extends K,? extends V>> entries) Writes multiple entries to the underlying system of record.

Methods inherited from class java.lang.Object

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

Constructor Detail

StripedWriteBehind

public StripedWriteBehind(ExecutionService executionService,
                          java.lang.String defaultThreadPool,
                          WriteBehindConfiguration config,
                          CacheLoaderWriter<K,V> cacheLoaderWriter)

Method Detail

start

public void start()

Description copied from interface: WriteBehind

Start the write behind queue

Specified by:

start in interface WriteBehind<K,V>

load

public V load(K key)
       throws java.lang.Exception

Description copied from interface: CacheLoaderWriter

Loads the value to be associated with the given key in the Cache using this CacheLoaderWriter instance.

Specified by:

load in interface CacheLoaderWriter<K,V>

Parameters:

key - the key that will map to the value returned

Returns:

the value to be mapped

Throws:

java.lang.Exception - if the value cannot be loaded

loadAll

public java.util.Map<K,V> loadAll(java.lang.Iterable<? extends K> keys)
                           throws java.lang.Exception

Description copied from interface: CacheLoaderWriter

Loads the values to be associated with the keys in the Cache using this CacheLoaderWriter instance. The returned Map should contain null mapped keys for values that couldn't be found.
The mapping that will be installed in the cache is the key as found in the input parameter keys mapped to the result of loadAllResult.get(key). Any other mapping will be ignored.

Specified by:

loadAll in interface CacheLoaderWriter<K,V>

Parameters:

keys - the keys that will be mapped to the values returned in the map

Returns:

the Map of values for each key passed in, where no mapping means no value to map.

Throws:

BulkCacheLoadingException - This writer must throw this exception to indicate partial success. The exception declares which keys were actually loaded (if any)

java.lang.Exception - a generic failure. All values will be considered not loaded in this case

write

public void write(K key,
                  V value)
           throws java.lang.Exception

Description copied from interface: CacheLoaderWriter

Writes a single entry to the underlying system of record, maybe a brand new value or an update to an existing value

Specified by:

write in interface CacheLoaderWriter<K,V>

Parameters:

key - the key of the mapping being installed or updated

value - the actual value being updated

Throws:

java.lang.Exception - if the write operation failed

See Also:

Cache.put(Object, Object)

writeAll

public void writeAll(java.lang.Iterable<? extends java.util.Map.Entry<? extends K,? extends V>> entries)
              throws BulkCacheWritingException,
                     java.lang.Exception

Description copied from interface: CacheLoaderWriter

Writes multiple entries to the underlying system of record. These can either be new entries or updates to existing ones. It is legal for this method to result in "partial success" where some subset of the entries are written. In this case a BulkCacheWritingException must be thrown (see below)

Specified by:

writeAll in interface CacheLoaderWriter<K,V>

Parameters:

entries - the key to value mappings

Throws:

BulkCacheWritingException - This writer must throw this exception to indicate partial success. The exception declares which keys were actually written (if any)

java.lang.Exception - a generic failure. All entries will be considered not written in this case

See Also:

Cache.putAll(java.util.Map)

delete

public void delete(K key)
            throws java.lang.Exception

Description copied from interface: CacheLoaderWriter

Deletes a single entry from the underlying system of record.

Specified by:

delete in interface CacheLoaderWriter<K,V>

Parameters:

key - the key to delete

Throws:

java.lang.Exception - if the write operation failed

See Also:

Cache.remove(Object)

deleteAll

public void deleteAll(java.lang.Iterable<? extends K> keys)
               throws BulkCacheWritingException,
                      java.lang.Exception

Description copied from interface: CacheLoaderWriter

Deletes a set of entry from the underlying system of record. It is legal for this method to result in "partial success" where some subset of the keys are deleted. In this case a BulkCacheWritingException must be thrown (see below)

Specified by:

deleteAll in interface CacheLoaderWriter<K,V>

Parameters:

keys - the keys to delete

Throws:

BulkCacheWritingException - This writer must throw this exception to indicate partial success. The exception declares which keys were actually deleted (if any)

java.lang.Exception - a generic failure. All entries will be considered not deleted in this case

See Also:

Cache.removeAll(java.util.Set)

stop

public void stop()

Description copied from interface: WriteBehind

Stop the coordinator and all the internal data structures.

This stops as quickly as possible without losing any previously added items. However, no guarantees are made towards the processing of these items. It's highly likely that items are still inside the internal data structures and not processed.

Specified by:

stop in interface WriteBehind<K,V>

getQueueSize

public long getQueueSize()

Description copied from interface: WriteBehind

Gets the best estimate for items in the queue still awaiting processing.

Specified by:

getQueueSize in interface WriteBehind<K,V>

Returns:

the amount of elements still awaiting processing.