About the Native Client C++ API
About the Native Client C++ API
The native client C++ API allows C++ and .NET developers to programmatically create, populate, and manage a Pivotal GemFire distributed system. The C++ library is thread-safe, except where specified otherwise in the online API documentation.
This chapter gives a general overview of the classes in the gemfire, gemfire_statistics, and gemfire_admin namespaces. For complete and current information on the classes listed here, see the online C++ API documentation.
- Cache Classes
- Region Classes
- Region Attribute Classes
- Application Plug-In Classes
- Event Handling Classes
- Statistics API
The native client C++ API has the following cache classes:
- CacheFactory. Use this class to create and configure a Cache instance. If cache.xml is specified, the cache is created based on the declarations loaded from that file.
- Cache. Entry point to the client caching API. The cache is created by calling the create function of the factory class, CacheFactory. Regions are configured and obtained using the Cache::createRegionFactory() API.
The native client C++ API has the following region classes:
Region. Provides functions for
managing regions and cached data. Use these functions to perform the following
- Retrieve information about the region, such as its parent region and region attribute objects.
- Invalidate or destroy the region.
- Create, update, invalidate and destroy region entries.
- Retrieve region entry keys, entry values, and RegionEntry objects, either individually or as entire sets.
- Retrieve the statistics object associated with the region.
- Set and get user-defined attributes.
- RegionEntry. Contains the key and value for the entry, and provides all non-distributed entry operations. This object's operations are not distributed and do not affect statistics.
Region Attribute Classes
The native client C++ API has the following region attribute classes:
- RegionAttributes. Holds all attribute values for a region and provides functions for retrieving all attribute settings. This class can be modified by the AttributesMutator class after region creation.
- AttributesMutator . Allows modification of an existing region’s attributes for application plug-ins and expiration actions. Each region has an AttributesMutator instance.
Application Plug-In Classes
The native client C++ API has the following application plug-in classes:
- CacheLoader. Loads data into a region on a cache miss.
- CacheWriter. Synchronously handles region and entry events before the events occur. Entry events are create, update, invalidate, and destroy. Region events are invalidate and destroy. This class has the ability to abort events.
- CacheListener. Handles region and entry events after they occur. Entry events are create, update, invalidate, and destroy. Region events are invalidate and destroy.
Event Handling Classes
The native client C++ API has the following event handling classes:
- RegionEvent. Provides information about the event, such as what region the event originated in, whether the event originated in a cache remote to the event handler, and whether the event resulted from a distributed operation.
- EntryEvent. Provides all available information for the RegionEvent, and provides entry-specific information such as the old and new entry values and whether the event resulted from a load operation.
The StatisticsType API represents a blueprint for the same type of Statistics. The StatisticsType API is a collection of StatisticDescriptor. Internally, each StatisticDescriptor describes data of each individual statistic. StatisticsFactory provides functionality for creating StatisticDescriptor, StatisticsType, and Statistics.
- CacheStatistics --This class defines common statistics functions. Region and RegionEntry both have functions that return a CacheStatistics object for accessing and resetting their statistics counts.
- StatisticDescriptor. An instance of this class describes a statistic whose value is updated by an application and may be archived by the native client. Each statistic has a type of either int, long, or double, and either a gauge or a counter. The value of a gauge can increase and decrease, and the value of a counter strictly increases. Create an instance of StatisticDescriptor by calling one of these StatisticsFactory functions: createDoubleCounter, createDoubleGauge, createIntCounter, createIntGauge ], createLongCounter, createLongGauge.
- StatisticsType. An instance of this class describes a logical collection of StatisticDescriptors. These descriptions are used to create an instance of Statistics. Create an instance of StatisticsType by calling StatisticsFactory::createType.
- Statistics. An instance of this class represents concrete Statistics of the associated StatisticsType. This class stores data related to all individual statistic objects. Create an instance by calling StatisticsFactory::createStatistics. This class has functions to get, set, and increment statistic values.
- StatisticsFactory. This class provides functions for creating instances of StatisticDescriptor, StatisticsType, and Statistics objects. This is a singleton class, and you acquire its instance by using StatisticsFactory::getExistingInstance.
To create new statistics, see Creating New Statistics.