Package uk.gov.gchq.gaffer.federated.simple.operation.handler

Class FederatedOperationHandler<P extends Operation>

java.lang.Object

uk.gov.gchq.gaffer.federated.simple.operation.handler.FederatedOperationHandler<P>

All Implemented Interfaces:

OperationHandler<P>

Direct Known Subclasses:

FederatedOutputHandler, SeparateOutputHandler

public class FederatedOperationHandler<P extends Operation>
extends Object
implements OperationHandler<P>

Main default handler for federated operations. Handles delegation to selected graphs and will sub class the operation to a FederatedOutputHandler if provided operation has output so that it is merged.

Field Summary

Fields

Modifier and Type	Field	Description
static String	OPT_AGGREGATE_ELEMENTS	The boolean operation option to specify if element merging should be applied or not.
static String	OPT_EXCLUDE_GRAPH_IDS	Graph IDs to exclude from the execution.
static String	OPT_GRAPH_IDS	The operation option for the Graph IDs that an operation should be executed on, will take preference over the short variant of this option.
static String	OPT_SEPARATE_RESULTS	A boolean option to specify if the results from each graph should be kept separate.
static String	OPT_SHORT_GRAPH_IDS	The short version of the operation option for the Graph IDs that an operation should be executed on.
static String	OPT_SKIP_FAILED_EXECUTE	A boolean option to specify if a graph should be skipped if execution fails on it e.g.
static String	OPT_USE_DFLT_GRAPH_IDS	A boolean option to specify to use the default graph IDs.

Constructor Summary

Constructors

Constructor	Description
FederatedOperationHandler()

Method Summary

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

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

OPT_GRAPH_IDS

public static final String OPT_GRAPH_IDS

The operation option for the Graph IDs that an operation should be executed on, will take preference over the short variant of this option.

See Also:

Constant Field Values

OPT_SHORT_GRAPH_IDS

public static final String OPT_SHORT_GRAPH_IDS

The short version of the operation option for the Graph IDs that an operation should be executed on.

See Also:

Constant Field Values

OPT_EXCLUDE_GRAPH_IDS

public static final String OPT_EXCLUDE_GRAPH_IDS

Graph IDs to exclude from the execution. If this option is set all graphs except the ones specified are executed on.

See Also:

Constant Field Values

OPT_USE_DFLT_GRAPH_IDS

public static final String OPT_USE_DFLT_GRAPH_IDS

A boolean option to specify to use the default graph IDs. The option is not specifically required as default graph IDs will be used as a fallback, but if set the whole chain will be forwarded rather than each individual operation so can speed things up.

See Also:

Constant Field Values

OPT_AGGREGATE_ELEMENTS

public static final String OPT_AGGREGATE_ELEMENTS

The boolean operation option to specify if element merging should be applied or not.

See Also:

Constant Field Values

OPT_SKIP_FAILED_EXECUTE

public static final String OPT_SKIP_FAILED_EXECUTE

A boolean option to specify if a graph should be skipped if execution fails on it e.g. continue executing on the rest of the graphs

See Also:

Constant Field Values

OPT_SEPARATE_RESULTS

public static final String OPT_SEPARATE_RESULTS

A boolean option to specify if the results from each graph should be kept separate. If set this will return a map where each key value is the graph ID and its respective result.

See Also:

Constant Field Values

Constructor Detail

FederatedOperationHandler

public FederatedOperationHandler()

Method Detail

doOperation

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

Description copied from interface: OperationHandler

Execute the given Operation.

Specified by:

doOperation in interface OperationHandler<P extends 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