Package com.gemstone.gemfire

The base package of the GemFire Java product, featuring highly concurrent distributed caching with cache event delivery, OQL querying, and remote cache administration, built using a DistributedSystem which includes a DistributedLockService.

See: Description

Interface Summary

Interface	Description
DataSerializable	An interface for objects whose state can be written/read as primitive types and strings ("data").
DataSerializable.Replaceable	Replaceable allows an object to write an alternative version of itself to a DataOutput.
Delta	This interface defines a contract between the application and GemFire that allows GemFire to determine whether an application object contains a delta, allows GemFire to extract the delta from an application object, and generate a new application object by applying a delta to an existing application object.
LogWriter	Defines methods available to clients that want to write a log message to their GemFire distributed system log file.
StatisticDescriptor	Describes an individual statistic whose value is updated by an application and may be archived by GemFire.
Statistics	Instances of this interface maintain the values of various application-defined statistics.
StatisticsFactory	Instances of this interface provide methods that create instances of Statistics.
StatisticsType	Used to describe a logical collection of statistics.
StatisticsTypeFactory	Instances of this interface provide methods that create instances of StatisticDescriptor and StatisticsType.

Class Summary

Class	Description
CancelCriterion	Abstract cancellation proxy for cancelling an operation, esp. a thread.
CanonicalInstantiator	CanonicalInstantiator is much like its parent Instantiator except that instead of needing to implement newInstance() you now must implement newInstance(DataInput).
CopyHelper	A static helper for optimally creating copies.
DataSerializer	Provides static helper methods for reading and writing non-primitive data when working with a DataSerializable.
Instantiator	Instantiator allows classes that implement DataSerializable to be registered with the data serialization framework.
SystemFailure	Catches and responds to JVM failure This class represents a catastrophic failure of the system, especially the Java virtual machine.

Exception Summary

Exception	Description
CancelException	Abstract root class of all GemFire exceptions representing system cancellation
CopyException	Indicates a failure to copy an object.
DeltaSerializationException	This exception wraps any checked exception encountered during invocation of Delta.fromDelta(java.io.DataInput) or Delta.toDelta(java.io.DataOutput) in GemFire.
ForcedDisconnectException	An ForcedDisconnectException is thrown when a GemFire application is removed from the distributed system due to membership constraints such as network partition detection.
GemFireCacheException	An GemFireCacheException is used to wrap a CacheException.
GemFireCheckedException	This is the abstract superclass of exceptions that are thrown and declared.
GemFireConfigException	A GemFireConfigException is used for failures while processing a GemFire configuration XML file.
GemFireException	This is the abstract superclass of exceptions that are thrown to indicate incorrect usage of GemFire.
GemFireIOException	A GemFireIOException is thrown when a GemFire operation failure is caused by an IOException.
IncompatibleSystemException	An IncompatibleSystemException is thrown when a new GemFire process tries to connect to an existing distributed system and its version is not the same as that of the distributed system.
InternalGemFireException	An InternalGemFireException is thrown when a low level, internal, operation fails due to no fault of the user.
InvalidDeltaException	An InvalidDeltaException is thrown when a delta cannot be successfully applied by the receiving peer/client.
InvalidValueException	An InvalidValueException is thrown when an attempt is made to set a configuration attribute to an invalid value is made.
InvalidVersionException
LicenseException	A LicenseException is thrown when the license check fails.
NoSystemException	A NoSystemException is thrown when a locator can not be found or connected to.
SerializationException	An exception indicating that a serialization or deserialization failed.
SystemConnectException	An SystemConnectException is thrown when a GemFire application tries to connect to an existing distributed system and is unable to contact all members of the distributed system to announce its presence.
SystemIsRunningException	A SystemIsRunningException is thrown when an operation is attempted that requires that the locator is stopped.
ThreadInterruptedException	Deprecated this class is no longer used
ToDataException	A ToDataException is thrown during serialization if DataSerializable.toData(java.io.DataOutput) throws an exception or if DataSerializer.toData(java.lang.Object, java.io.DataOutput) is called and returns false.
UncreatedSystemException	An UncreatedSystemException is thrown when the specified locator's directory or configuration file can not be found.
UnmodifiableException	A UnmodifiableException is thrown when a an attempt is made to modify a GemFire member configuration attribute that can not currently be modified.
UnstartedSystemException	An UnstartedSystemException is thrown when the specified locator exists but is not running or could not be connected to.

Error Summary

Error	Description
GemFireRethrowable	This error is used by GemFire for internal purposes.
InternalGemFireError	Indicates that serious error has occurred within the GemFire system.

Package com.gemstone.gemfire Description

The base package of the GemFire Java product, featuring highly concurrent distributed caching with cache event delivery, OQL querying, and remote cache administration, built using a DistributedSystem which includes a DistributedLockService.

This package contains classes that are used throughout GemFire, providing enhanced serialization performance using the DataSerializable feature and the ability to profile your GemFire application using a handy Statistics infrastructure.

GemFire Statistics

The ability to monitor and analyze the behavior and performance of an application can ease the job of optimization. To aid in this analysis, GemFire provides the ability to register and capture application statistics. An application statistic is simply a number that the application is free to modify and that is monitored by the GemFire's statistics collector. The statistics may be monitored at runtime using the Admin API or GemFire JMX Agent.

Each application statistic is described by a StatisticDescriptor instance. Logical groupings of application statistics are described by a StatisticsType instance that contains the name and description of each statistic. Each instance of an type is represented by an instance of Statistics. The descriptors, types, and instances are created using an instance of the StatisticsFactory interface. Each statistics instance (there may be multiple instances of a statistics type) can be identified by a text id and/or a numeric id. The name, description, etc. of the statistic and its type are available in the Admin API or GemFire JMX Agent.

An application can get, set, and increment the value of a statistic using methods of the Statistics interface. If statistics sampling has been enabled a thread in the application VM periodically reads the values of application statistics allowing them to be viewed by the Admin API and GemFire JMX Agent. Statistics may also be archived to a file, the name and location of which may be configured when creating a DistributedSystem.

In addition to application statistics, GemFire maintains statistics about the distributed system, the distributed cache, and the physical machine on which it runs. These statistics can be monitored, viewed, and archived just like application statistics.