com.basho.riak.client.query

Class MapReduce

java.lang.Object

com.basho.riak.client.query.MapReduce

All Implemented Interfaces:

RiakOperation<MapReduceResult>

Direct Known Subclasses:

BucketKeyMapReduce, BucketMapReduce, IndexMapReduce, SearchMapReduce

public abstract class MapReduce
extends Object
implements RiakOperation<MapReduceResult>

An operation for defining and runnig a Map/Reduce query on Riak.

See Map/Reduce for details.

Author:

russell

See Also:

IRiakClient.mapReduce(), IRiakClient.mapReduce(String)

Constructor Summary

Constructors

Constructor and Description
MapReduce(RawClient client) Create the MapRedcue operation with the RawClient to delegate to.

Method Summary

Methods

Modifier and Type	Method and Description
MapReduce	addLinkPhase(String bucket, String tag) Create a Link Phase that points to bucket / tag keep will be false
MapReduce	addLinkPhase(String bucket, String tag, boolean keep) Add a Link Phase that points to bucket / tag .
MapReduce	addMapPhase(Function phaseFunction) Add a MapPhase
MapReduce	addMapPhase(Function phaseFunction, boolean keep) Add MapPhase to the query
MapReduce	addMapPhase(Function phaseFunction, Object arg) Add a MapPhase
MapReduce	addMapPhase(Function phaseFunction, Object arg, boolean keep) Add a MapPhase
MapReduce	addReducePhase(Function phaseFunction) Add a ReducePhase
MapReduce	addReducePhase(Function phaseFunction, boolean keep) Add ReducePhase to the query
MapReduce	addReducePhase(Function phaseFunction, Object arg) Add a ReducePhase
MapReduce	addReducePhase(Function phaseFunction, Object arg, boolean keep) Add a ReducePhase
MapReduceResult	execute() Run the Map/Reduce job against the RawClient the operation was constructed with.
MapReduce	timeout(long timeout) Set the operations timeout
protected void	validate() Check that this map/reduce job is valid
protected abstract void	writeInput(org.codehaus.jackson.JsonGenerator jsonGenerator) Override to write the input specification of the M/R job.

Methods inherited from class java.lang.Object

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

Constructor Detail

MapReduce

public MapReduce(RawClient client)

Create the MapRedcue operation with the RawClient to delegate to.

Parameters:

client - a RawClient

See Also:

IRiakClient.mapReduce(), IRiakClient.mapReduce(String)

Method Detail

execute

public MapReduceResult execute()
                        throws RiakException

Run the Map/Reduce job against the RawClient the operation was constructed with.

Specified by:

execute in interface RiakOperation<MapReduceResult>

Returns:

a MapReduceResult containing the results of the query.

Throws:

RiakException

InvalidMapReduceException

validate

protected void validate()

Check that this map/reduce job is valid

Throws:

InvalidMapReduceException

timeout

public MapReduce timeout(long timeout)

Set the operations timeout

Parameters:

timeout -

Returns:

this

addMapPhase

public MapReduce addMapPhase(Function phaseFunction,
                    boolean keep)

Add MapPhase to the query

Parameters:

phaseFunction - the Function

keep - keep the results and return them with the query results?

Returns:

this

addMapPhase

public MapReduce addMapPhase(Function phaseFunction,
                    Object arg,
                    boolean keep)

Add a MapPhase

Parameters:

phaseFunction - the Function

arg - an argument that will be passed to the phase verbatim (Object#toString)

keep - if the result should be returned or merely provide input for the next phase.

Returns:

this

addMapPhase

public MapReduce addMapPhase(Function phaseFunction,
                    Object arg)

Add a MapPhase

Parameters:

phaseFunction - the Function

arg - an argument that will be passed to the phase verbatim (Object#toString)

Returns:

this

addMapPhase

public MapReduce addMapPhase(Function phaseFunction)

Add a MapPhase

Parameters:

phaseFunction - the Function

Returns:

this

addReducePhase

public MapReduce addReducePhase(Function phaseFunction,
                       boolean keep)

Add ReducePhase to the query

Parameters:

phaseFunction - the Function

keep - keep the results and return them with the query results?

Returns:

this

addReducePhase

public MapReduce addReducePhase(Function phaseFunction,
                       Object arg,
                       boolean keep)

Add a ReducePhase

Parameters:

phaseFunction - the Function

arg - an argument that will be passed to the phase verbatim (Object#toString)

keep - if the result should be returned or merely provide input for the next phase.

Returns:

this

addReducePhase

public MapReduce addReducePhase(Function phaseFunction,
                       Object arg)

Add a ReducePhase

Parameters:

phaseFunction - the Function

arg - an argument that will be passed to the phase verbatim

Returns:

this

addReducePhase

public MapReduce addReducePhase(Function phaseFunction)

Add a ReducePhase

Parameters:

phaseFunction -

Returns:

this

addLinkPhase

public MapReduce addLinkPhase(String bucket,
                     String tag,
                     boolean keep)

Add a Link Phase that points to bucket / tag .

Parameters:

bucket - the bucket at the end of the link (or "_" or "" for wildcard)

tag - the tag (or ("_", or "" for wildcard)

keep - to keep the result of this phase and return it at the end of the operation

addLinkPhase

public MapReduce addLinkPhase(String bucket,
                     String tag)

Create a Link Phase that points to bucket / tag keep will be false

Parameters:

bucket - the bucket at the end of the link (or "_" or "" for wildcard)

tag - the tag (or ("_", or "" for wildcard)

writeInput

protected abstract void writeInput(org.codehaus.jackson.JsonGenerator jsonGenerator)
                            throws IOException

Override to write the input specification of the M/R job.

Parameters:

jsonGenerator - a Jackson JsonGenerator to write the input spec to

Throws:

IOException