K - the type of keys maintained by this mapV - the type of mapped valuespublic interface CacheWriter<K,V>
Under Default Consistency, the non-batch writer methods are atomic with respect to the corresponding cache operation.
For batch methods under Default Consistency, the entire cache operation
is not required to be atomic in Cache and is therefore not required to
be atomic in the writer. As individual writer operations can fail, cache
operations are not required to occur until after the writer batch method has
returned or, in the case of partial success, thrown an exception. In the case
of partial success, the collection of entries return must only contain
those entries that failed.
The entry passed into write(Cache.Entry) is independent
of the cache mapping for that key, meaning that if the value changes in the
cache or is removed it does not change the entry.
CacheLoader| Modifier and Type | Method and Description |
|---|---|
void |
delete(Object key)
Delete the cache entry from the external resource.
|
void |
deleteAll(Collection<?> keys)
Remove data and keys from the external resource for the given collection of
keys, if present.
|
void |
write(Cache.Entry<? extends K,? extends V> entry)
Write the specified value under the specified key to the external resource.
|
void |
writeAll(Collection<Cache.Entry<? extends K,? extends V>> entries)
Write the specified entries to the external resource.
|
void write(Cache.Entry<? extends K,? extends V> entry) throws CacheWriterException
This method is intended to support both key/value creation and value update for a specific key.
entry - the entry to be writtenCacheWriterException - if the write fails. If thrown the
cache mutation will not occur.void writeAll(Collection<Cache.Entry<? extends K,? extends V>> entries) throws CacheWriterException
The order that individual writes occur is undefined, as
Cache.putAll(java.util.Map) also has undefined ordering.
If this operation fails (by throwing an exception) after a partial success, the writer must remove any successfully written entries from the entries collection so that the caching implementation knows what succeeded and can mutate the cache.
entries - a mutable collection to write. Upon invocation, it contains
the entries to write for write-through. Upon return the
collection must only contain entries that were not
successfully written. (see partial success above)CacheWriterException - if one or more of the writes fail. If
thrown cache mutations will occur for
entries that succeeded.void delete(Object key) throws CacheWriterException
Expiry of a cache entry is not a delete hence will not cause this method to be invoked.
This method is invoked even if no mapping for the key exists.
key - the key that is used for the delete operationCacheWriterException - if delete fails. If thrown the cache delete will
not occur.void deleteAll(Collection<?> keys) throws CacheWriterException
The order that individual deletes occur is undefined, as
Cache.removeAll(java.util.Set) also has undefined ordering.
If this operation fails (by throwing an exception) after a partial success, the writer must remove any successfully written entries from the entries collection so that the caching implementation knows what succeeded and can mutate the cache.
Expiry of a cache entry is not a delete hence will not cause this method to be invoked.
This method may include keys even if there is no mapping for that key, in which case the data represented by that key should be removed from the underlying resource.
keys - a mutable collection of keys for entries to delete. Upon
invocation, it contains the keys to delete for write-through.
Upon return the collection must only contain the keys that were
not successfully deleted. (see partial success above)CacheWriterException - if one or more deletes fail. If thrown
cache deletes will occur for entries that
succeeded.Copyright © 2019. All rights reserved.