Package uk.gov.gchq.gaffer.store.operation.handler

Interface OperationHandler<OP extends Operation>

All Known Subinterfaces:

AddToCacheHandler<OP>, OperationWithSchemaHandler<OP,O>, OutputOperationHandler<OP,O>

All Known Implementing Classes:

AbstractGenerateSplitPointsFromSampleHandler, AbstractGetRDDHandler, AbstractImportKeyValuePairRDDToAccumuloHandler, AbstractSampleElementsForSplitPointsHandler, AbstractSplitStoreFromRDDOfElementsHandler, AddElementsFromFileHandler, AddElementsFromHdfsHandler, AddElementsFromKafkaHandler, AddElementsFromSocketHandler, AddElementsHandler, AddElementsHandler, AddNamedOperationHandler, AddNamedViewHandler, AddSchemaToLibraryHandler, AddStorePropertiesToLibraryHandler, AggregateHandler, CancelScheduledJobHandler, CountAllElementsDefaultViewHandler, CountGroupsHandler, CountHandler, DeleteAllDataHandler, DeleteNamedOperationHandler, DeleteNamedViewHandler, DiscardOutputHandler, ExportOperationHandler, ExportToGafferResultCacheHandler, ExportToHandler, ExportToLocalFileHandler, ExportToOtherAuthorisedGraphHandler, ExportToOtherGraphHandler, ExportToSetHandler, FederatedAddGraphHandler, FederatedAddGraphHandlerParent, FederatedAddGraphWithHooksHandler, FederatedChangeGraphAccessHandler, FederatedChangeGraphIdHandler, FederatedDelegateToHandler, FederatedGetAllGraphIDHandler, FederatedGetAllGraphInfoHandler, FederatedNoOutputHandler, FederatedOperationHandler, FederatedOutputHandler, FederatedOutputIterableHandler, FederatedRemoveGraphAndDeleteAllDataHandler, FederatedRemoveGraphHandler, FilterHandler, ForEachHandler, GenerateElementsHandler, GenerateObjectsHandler, GenerateSplitPointsFromSampleHandler, GetAdjacentIdsHandler, GetAdjacentIdsHandler, GetAllElementsHandler, GetAllElementsHandler, GetAllJobDetailsHandler, GetAllNamedOperationsHandler, GetAllNamedViewsHandler, GetDataFrameOfElementsHandler, GetElementsBetweenSetsHandler, GetElementsBetweenSetsPairsHandler, GetElementsHandler, GetElementsHandler, GetElementsInRangesHandler, GetElementsWithinSetHandler, GetExportHandler, GetExportsHandler, GetFromEndpointHandler, GetGafferResultCacheExportHandler, GetGraphFrameOfElementsHandler, GetJavaRDDOfAllElementsHandler, GetJavaRDDOfElementsHandler, GetJavaRDDOfElementsInRangesHandler, GetJobDetailsHandler, GetJobResultsHandler, GetProxyPropertiesHandler, GetProxyUrlHandler, GetRDDOfAllElementsHandler, GetRDDOfElementsHandler, GetRDDOfElementsInRangesHandler, GetSchemaHandler, GetSetExportHandler, GetTraitsHandler, GetVariableHandler, GetVariablesHandler, GetWalksHandler, HasTraitHandler, HdfsSplitStoreFromFileHandler, IfHandler, ImportAccumuloKeyValueFilesHandler, ImportFromLocalFileHandler, ImportJavaRDDOfElementsHandler, ImportKeyValueJavaPairRDDToAccumuloHandler, ImportKeyValuePairRDDToAccumuloHandler, ImportRDDOfElementsHandler, JoinHandler, LimitHandler, MapHandler, MaxHandler, MinHandler, NamedOperationHandler, OperationChainHandler, OperationChainHandler, ReduceHandler, SampleDataForSplitPointsHandler, SampleElementsForSplitPointsHandler, ScoreOperationChainHandler, SetVariableHandler, SortHandler, SplitStoreFromFileHandler, SplitStoreFromIterableHandler, SplitStoreFromJavaRDDOfElementsHandler, SplitStoreFromRDDOfElementsHandler, SummariseGroupOverRangesHandler, ToArrayHandler, ToCsvHandler, ToEntitySeedsHandler, ToListHandler, ToMapHandler, ToSetHandler, ToSingletonListHandler, ToStreamHandler, ToVerticesHandler, TransformHandler, ValidateHandler, ValidateOperationChainHandler, WhileHandler

public interface OperationHandler<OP extends Operation>

An OperationHandler defines how to handle a specific Operation. All instances of an OperationHandler must be stateless as they are reused for all concurrent operations.

Method Summary

Modifier and Type	Method	Description
Object	doOperation(OP operation, Context context, Store store)	Execute the given Operation.

Method Detail

doOperation

Object doOperation(OP operation,
                   Context context,
                   Store store)
            throws OperationException

Execute the given Operation.

Parameters:

operation - the Operation to be executed

context - the operation chain context, containing the user who executed the operation

store - the Store the operation should be run on

Returns:

the output for the operation or null.

Throws:

OperationException - thrown if the operation fails