Package com.google.appengine.api.memcache

The memcache API provides access to fast but unreliable data storage, which may also be accessed via the JCache API.

See:
Description

Interface Summary

ErrorHandler	Handles errors raised by the MemcacheService, registered with MemcacheService.setErrorHandler(ErrorHandler).
MemcacheService	The Java API for the App Engine Memcache service.
Stats	Statistics from the cache, available via MemcacheService.getStatistics()

Class Summary

Expiration	Expiration specifications on MemcacheService.putAll(Map , Expiration) and MemcacheService.put(Object, Object, Expiration) operations.
LogAndContinueErrorHandler	The default error handler, which will cause most service errors to behave as though there were a cache miss, not an error.
MemcacheSerialization	Static serialization helpers shared by MemcacheServiceImpl and com.google.appengine.api.memcache.dev.LocalMemcacheService.
MemcacheSerialization.ValueAndFlags	Tuple of a serialized byte array value and associated flags to interpret that value.
MemcacheServiceFactory	The factory by which users acquire a handle to the MemcacheService.
StrictErrorHandler	A strict error handler, which will throw MemcacheServiceException for any service error condition.

Enum Summary

MemcacheSerialization.Flag	Values used as flags on the MemcacheService's values.
MemcacheService.SetPolicy	Cache replacement strategies for MemcacheService.put(java.lang.Object, java.lang.Object, com.google.appengine.api.memcache.Expiration, com.google.appengine.api.memcache.MemcacheService.SetPolicy) operations, indicating how to handle putting a value that already exists.

Exception Summary

InvalidValueException	Thrown when a cache entry has content, but it cannot be read.
MemcacheServiceException	An exception for backend non-availability or similar error states which may occur, but are not necessarily indicative of a coding or usage error by the application.

Package com.google.appengine.api.memcache Description

The memcache API provides access to fast but unreliable data storage, which may also be accessed via the JCache API. Objects may be stored in the cache with an explicit expiration time, but may also be evicted before that expiration to make room for newer, more active entries. More information is available in the on-line documentation.

The cache is accessed via a MemcacheService object, obtained from the MemcacheServiceFactory. It offers the cache as a map from key Object to value Object.

In the Development Server, the system property memcache.maxsize can be set to limit the available cache, taking values like "100M" (the default), "10K", or "768" (bytes).

Because the cache offers best-effort data storage, by default most errors are treated as a cache miss. More explicit error handling can be installed via MemcacheService.setErrorHandler(ErrorHandler).