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# Class CacheStoreAdapter<TK, TV>

Cache storage convenience adapter. It provides default implementation for bulk operations, such as `LoadAll`, `PutAll` and `RemoveAll` by sequentially calling corresponding `Load`, `Put` and `Remove` operations. Use this adapter whenever such behaviour is acceptable. However in many cases it maybe more preferable to take advantage of database batch update functionality, and therefore default adapter implementation may not be the best option.

Note that `LoadCache` method has empty implementation because it is essentially up to the user to invoke it with specific arguments.

##### Inheritance

System.Object
CacheStoreAdapter<TK, TV>

##### Implements

ICacheStore<TK, TV>
ICacheStore

##### Inherited Members

System.Object.ToString()
System.Object.Equals(System.Object)
System.Object.Equals(System.Object, System.Object)
System.Object.ReferenceEquals(System.Object, System.Object)
System.Object.GetHashCode()
System.Object.GetType()
System.Object.MemberwiseClone()

###### Namespace: Apache.Ignite.Core.Cache.Store

###### Assembly: Apache.Ignite.Core.dll

##### Syntax

    public abstract class CacheStoreAdapter<TK, TV> : ICacheStore<TK, TV>, ICacheStore

##### Type Parameters

Name | Description
--- | ---
TK | Key type.
TV | Value type.

### Methods

#### Delete(TK)

Delete the cache entry from the external resource.

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.

##### Declaration

    public abstract void Delete(TK key)

##### Parameters

Type | Name | Description
--- | --- | ---
TK | key | The key that is used for the delete operation.

#### DeleteAll(IEnumerable<TK>)

Remove data and keys from the external resource for the given collection of keys, if present.

The order that individual deletes occur is undefined.

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.

##### Declaration

    public virtual void DeleteAll(IEnumerable<TK> keys)

##### Parameters

Type | Name | Description
--- | --- | ---
System.Collections.Generic.IEnumerable<TK> | 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.

#### Load(TK)

Loads an object. Application developers should implement this method to customize the loading of a value for a cache entry. This method is called by a cache when a requested entry is not in the cache. If the object can't be loaded `null` should be returned.

##### Declaration

    public abstract TV Load(TK key)

##### Parameters

Type | Name | Description
--- | --- | ---
TK | key | The key identifying the object being loaded.

##### Returns

Type | Description
--- | ---
TV | The value for the entry that is to be stored in the cache or `null` if the object can't be loaded

#### LoadAll(IEnumerable<TK>)

Loads multiple objects. Application developers should implement this method to customize the loading of cache entries. This method is called when the requested object is not in the cache. If an object can't be loaded, it is not returned in the resulting map.

##### Declaration

    public virtual IEnumerable<KeyValuePair<TK, TV>> LoadAll(IEnumerable<TK> keys)

##### Parameters

Type | Name | Description
--- | --- | ---
System.Collections.Generic.IEnumerable<TK> | keys | Keys identifying the values to be loaded.

##### Returns

Type | Description
--- | ---
System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TK, TV>> | A map of key, values to be stored in the cache.

#### LoadCache(Action<TK, TV>, Object[])

Loads all values from underlying persistent storage. Note that keys are not passed, so it is up to implementation to figure out what to load. This method is called whenever LocalLoadCache(ICacheEntryFilter<TK, TV>, Object[]) method is invoked which is usually to preload the cache from persistent storage.

This method is optional, and cache implementation does not depend on this method to do anything.

For every loaded value method provided action should be called. The action will then make sure that the loaded value is stored in cache.

##### Declaration

    public virtual void LoadCache(Action<TK, TV> act, params object[] args)

##### Parameters

Type | Name | Description
--- | --- | ---
System.Action<TK, TV> | act | Action for loaded values.
System.Object[] | args | Optional arguments passed to LocalLoadCache(ICacheEntryFilter<TK, TV>, Object[]) method.

#### SessionEnd(Boolean)

Tells store to commit or rollback a transaction depending on the value of the `commit` parameter.

##### Declaration

    public virtual void SessionEnd(bool commit)

##### Parameters

Type | Name | Description
--- | --- | ---
System.Boolean | commit | `True` if transaction should commit, `false` for rollback.

#### Write(TK, TV)

Write the specified value under the specified key to the external resource.

This method is intended to support both key/value creation and value update.

##### Declaration

    public abstract void Write(TK key, TV val)

##### Parameters

Type | Name | Description
--- | --- | ---
TK | key | Key to write.
TV | val | Value to write.

#### WriteAll(IEnumerable<KeyValuePair<TK, TV>>)

Writes all.

##### Declaration

    public virtual void WriteAll(IEnumerable<KeyValuePair<TK, TV>> entries)

##### Parameters

Type | Name | Description
--- | --- | ---
System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TK, TV>> | entries | The map.

### Implements

ICacheStore<TK, TV>
ICacheStore