com.allanbank.mongodb.builder

Class MapReduce.Builder

java.lang.Object

com.allanbank.mongodb.builder.MapReduce.Builder

Enclosing class:

MapReduce

public static class MapReduce.Builder
extends Object

Helper for creating immutable MapReduce commands.

API Notice:

This class is part of the driver's API. Public and protected members will be deprecated for at least 1 non-bugfix release (version numbers are <major>.<minor>.<bugfix>) before being removed or modified.

Copyright ©:

2011-2012, Allanbank Consulting, Inc., All Rights Reserved

Field Summary

Fields

Modifier and Type	Field and Description
protected String	myFinalizeFunction The finalize function to apply to the final results of the reduce function.
protected boolean	myJsMode If true limits the translation of the documents to an from BSON/JavaScript.
protected boolean	myKeepTemp If true then the temporary collections created during the map/reduce should not be dropped.
protected int	myLimit Limits the number of objects to be used as input to the map/reduce.
protected String	myMapFunction The map functions to apply to each selected document.
protected String	myOutputDatabase The name of the output database if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.
protected String	myOutputName The name of the output collection if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.
protected MapReduce.OutputType	myOutputType The handling for the output of the map/reduce.
protected Document	myQuery The query to select the document to run the map/reduce against.
protected ReadPreference	myReadPreference The read preference to use.
protected String	myReduceFunction The reduce function to apply to the emitted output of the map function.
protected Document	myScope The scoped values to expose to the map/reduce/finalize functions.
protected Document	mySort The sort to apply to the input objects.
protected boolean	myVerbose If true emits progress messages in the server logs.

Constructor Summary

Constructors

Constructor and Description
MapReduce.Builder()

Method Summary

Methods

Modifier and Type	Method and Description
MapReduce	build() Constructs a new FindAndModify object from the state of the builder.
MapReduce.Builder	setFinalizeFunction(String finalize) Sets the finalize function to apply to the final results of the reduce function.
MapReduce.Builder	setJsMode(boolean jsMode) Sets to true to limit the translation of the documents to an from BSON/JavaScript.
MapReduce.Builder	setKeepTemp(boolean keepTemp) Sets to true to drop the temporary collections created during the map/reduce.
MapReduce.Builder	setLimit(int limit) Sets the limit for the number of objects to be used as input to the map/reduce.
MapReduce.Builder	setMapFunction(String map) Sets the map functions to apply to each selected document.
MapReduce.Builder	setOutputDatabase(String outputDatabase) Sets the name of the output database if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.
MapReduce.Builder	setOutputName(String outputName) Sets the name of the output collection if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.
MapReduce.Builder	setOutputType(MapReduce.OutputType outputType) Sets the handling for the output of the map/reduce.
MapReduce.Builder	setQuery(DocumentAssignable query) Sets the query to select the documents to run the map/reduce against.
MapReduce.Builder	setReadPreference(ReadPreference readPreference) Sets the ReadPreference specifying which servers may be used to execute the MapReduce command.
MapReduce.Builder	setReduceFunction(String reduce) Sets the reduce function to apply to the emitted output of the map function.
MapReduce.Builder	setScope(DocumentAssignable scope) Sets the scoped values to expose to the map/reduce/finalize functions.
MapReduce.Builder	setSort(DocumentAssignable sort) Sets the sort to apply to the input objects.
MapReduce.Builder	setSort(IntegerElement... sortFields) Sets the sort to apply to the input objects.
MapReduce.Builder	setVerbose(boolean verbose) Sets to true to emit progress messages in the server logs.

Methods inherited from class java.lang.Object

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

Field Detail

myFinalizeFunction

protected String myFinalizeFunction

The finalize function to apply to the final results of the reduce function.

myJsMode

protected boolean myJsMode

If true limits the translation of the documents to an from BSON/JavaScript.

myKeepTemp

protected boolean myKeepTemp

If true then the temporary collections created during the map/reduce should not be dropped.

myLimit

protected int myLimit

Limits the number of objects to be used as input to the map/reduce.

myMapFunction

protected String myMapFunction

The map functions to apply to each selected document.

myOutputDatabase

protected String myOutputDatabase

The name of the output database if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.

myOutputName

protected String myOutputName

The name of the output collection if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.

myOutputType

protected MapReduce.OutputType myOutputType

The handling for the output of the map/reduce.

myQuery

protected Document myQuery

The query to select the document to run the map/reduce against.

myReadPreference

protected ReadPreference myReadPreference

The read preference to use.

myReduceFunction

protected String myReduceFunction

The reduce function to apply to the emitted output of the map function.

myScope

protected Document myScope

The scoped values to expose to the map/reduce/finalize functions.

mySort

protected Document mySort

The sort to apply to the input objects. Useful for optimization, like sorting by the emit key for fewer reduces.

myVerbose

protected boolean myVerbose

If true emits progress messages in the server logs.

Constructor Detail

MapReduce.Builder

public MapReduce.Builder()

Method Detail

build

public MapReduce build()

Constructs a new FindAndModify object from the state of the builder.

Returns:

The new FindAndModify object.

setFinalizeFunction

public MapReduce.Builder setFinalizeFunction(String finalize)

Sets the finalize function to apply to the final results of the reduce function.

Parameters:

finalize - The finalize function to apply to the final results of the reduce function.

Returns:

This builder for chaining method calls.

setJsMode

public MapReduce.Builder setJsMode(boolean jsMode)

Sets to true to limit the translation of the documents to an from BSON/JavaScript.

Parameters:

jsMode - True to limit the translation of the documents to an from BSON/JavaScript.

Returns:

This builder for chaining method calls.

setKeepTemp

public MapReduce.Builder setKeepTemp(boolean keepTemp)

Sets to true to drop the temporary collections created during the map/reduce.

Parameters:

keepTemp - True to drop the temporary collections created during the map/reduce.

Returns:

This builder for chaining method calls.

setLimit

public MapReduce.Builder setLimit(int limit)

Sets the limit for the number of objects to be used as input to the map/reduce.

Parameters:

limit - The limit for the number of objects to be used as input to the map/reduce.

Returns:

This builder for chaining method calls.

setMapFunction

public MapReduce.Builder setMapFunction(String map)

Sets the map functions to apply to each selected document.

Parameters:

map - The map functions to apply to each selected document.

Returns:

This builder for chaining method calls.

setOutputDatabase

public MapReduce.Builder setOutputDatabase(String outputDatabase)

Sets the name of the output database if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.

Parameters:

outputDatabase - The name of the output database if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.

Returns:

This builder for chaining method calls.

setOutputName

public MapReduce.Builder setOutputName(String outputName)

Sets the name of the output collection if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.

Parameters:

outputName - The name of the output collection if the output type is One of MapReduce.OutputType.REPLACE, MapReduce.OutputType.MERGE, or MapReduce.OutputType.REDUCE.

Returns:

This builder for chaining method calls.

setOutputType

public MapReduce.Builder setOutputType(MapReduce.OutputType outputType)

Sets the handling for the output of the map/reduce.

Parameters:

outputType - The handling for the output of the map/reduce.

Returns:

This builder for chaining method calls.

setQuery

public MapReduce.Builder setQuery(DocumentAssignable query)

Sets the query to select the documents to run the map/reduce against.

Parameters:

query - The query to select the documents to run the map/reduce against.

Returns:

This builder for chaining method calls.

setReadPreference

public MapReduce.Builder setReadPreference(ReadPreference readPreference)

Sets the ReadPreference specifying which servers may be used to execute the MapReduce command.

If not set or set to null then the MongoCollection instance's ReadPreference will be used.

Parameters:

readPreference - The read preferences specifying which servers may be used.

Returns:

This builder for chaining method calls.

See Also:

MongoCollection.getReadPreference()

setReduceFunction

public MapReduce.Builder setReduceFunction(String reduce)

Sets the reduce function to apply to the emitted output of the map function.

Parameters:

reduce - The reduce function to apply to the emitted output of the map function.

Returns:

This builder for chaining method calls.

setScope

public MapReduce.Builder setScope(DocumentAssignable scope)

Sets the scoped values to expose to the map/reduce/finalize functions.

Parameters:

scope - The scoped values to expose to the map/reduce/finalize functions.

Returns:

This builder for chaining method calls.

setSort

public MapReduce.Builder setSort(DocumentAssignable sort)

Sets the sort to apply to the input objects. Useful for optimization, like sorting by the emit key for fewer reduces.

Parameters:

sort - The sort to apply to the input objects. Useful for optimization, like sorting by the emit key for fewer reduces.

Returns:

This builder for chaining method calls.

setSort

public MapReduce.Builder setSort(IntegerElement... sortFields)

Sets the sort to apply to the input objects. Useful for optimization, like sorting by the emit key for fewer reduces.

This method is intended to be used with the Sort class's static methods:

 
 import static com.allanbank.mongodb.builder.Sort.asc;
 import static com.allanbank.mongodb.builder.Sort.desc;
 
 MapReduce.Builder builder = new Find.Builder();
 
 builder.setSort( asc("f"), desc("g") );
 ...
 
 

Parameters:

sortFields - The sort to apply to the input objects. Useful for optimization, like sorting by the emit key for fewer reduces.

Returns:

This builder for chaining method calls.

setVerbose

public MapReduce.Builder setVerbose(boolean verbose)

Sets to true to emit progress messages in the server logs.

Parameters:

verbose - True to emit progress messages in the server logs.

Returns:

This builder for chaining method calls.