Package com.mongodb

Class MapReduceCommand

  • public class MapReduceCommand
extends Object
    This class groups the argument for a map/reduce operation and can build the underlying command object
    MongoDB documentation
    Map-Reduce

    • Constructor Detail

      • MapReduceCommand

        public MapReduceCommand​(DBCollection inputCollection,
                        String map,
                        String reduce,
                        @Nullable
                        String outputCollection,
                        MapReduceCommand.OutputType type,
                        DBObject query)
        Represents the command for a map reduce operation Runs the command in REPLACE output type to a named collection
        Parameters:
        inputCollection - collection to use as the source documents to perform the map reduce operation.
        map - a JavaScript function that associates or "maps" a value with a key and emits the key and value pair.
        reduce - a JavaScript function that "reduces" to a single object all the values associated with a particular key.
        outputCollection - optional - leave null if want to get the result inline
        type - the type of output
        query - specifies the selection criteria using query operators for determining the documents input to the map function.
        MongoDB documentation
        Map Reduce Command

    • Method Detail

      • setVerbose

        public void setVerbose​(Boolean verbose)
        Sets the verbosity of the MapReduce job, defaults to 'true'
        Parameters:
        verbose - The verbosity level.

      • isVerbose

        public Boolean isVerbose()
        Gets the verbosity of the MapReduce job.
        Returns:
        the verbosity level.

      • getInput

        public String getInput()
        Get the name of the collection the MapReduce will read from
        Returns:
        name of the collection the MapReduce will read from

      • getMap

        public String getMap()
        Get the map function, as a JS String
        Returns:
        the map function (as a JS String)

      • getReduce

        public String getReduce()
        Gets the reduce function, as a JS String
        Returns:
        the reduce function (as a JS String)

      • getOutputTarget

        @Nullable
public String getOutputTarget()
        Gets the output target (name of collection to save to) This value is nullable only if OutputType is set to INLINE
        Returns:
        The outputCollection

      • getFinalize

        @Nullable
public String getFinalize()
        Gets the Finalize JS Function
        Returns:
        The finalize function (as a JS String).

      • setFinalize

        public void setFinalize​(@Nullable
                        String finalize)
        Sets the Finalize JS Function
        Parameters:
        finalize - The finalize function (as a JS String)

      • getQuery

        @Nullable
public DBObject getQuery()
        Gets the query to run for this MapReduce job
        Returns:
        The query object

      • getSort

        @Nullable
public DBObject getSort()
        Gets the (optional) sort specification object
        Returns:
        the Sort DBObject

      • setSort

        public void setSort​(@Nullable
                    DBObject sort)
        Sets the (optional) sort specification object
        Parameters:
        sort - The sort specification object

      • getLimit

        public int getLimit()
        Gets the (optional) limit on input
        Returns:
        The limit specification object

      • setLimit

        public void setLimit​(int limit)
        Sets the (optional) limit on input
        Parameters:
        limit - The limit specification object

      • getMaxTime

        public long getMaxTime​(TimeUnit timeUnit)
        Gets the max execution time for this command, in the given time unit.
        Parameters:
        timeUnit - the time unit to return the value in.
        Returns:
        the maximum execution time
        Since:
        2.12.0

      • setMaxTime

        public void setMaxTime​(long maxTime,
                       TimeUnit timeUnit)
        Sets the max execution time for this command, in the given time unit.
        Parameters:
        maxTime - the maximum execution time. A non-zero value requires a server version >= 2.6
        timeUnit - the time unit that maxTime is specified in
        Since:
        2.12.0

      • getScope

        @Nullable
public Map<String,​Object> getScope()
        Gets the (optional) JavaScript scope
        Returns:
        The JavaScript scope

      • setScope

        public void setScope​(@Nullable
                     Map<String,​Object> scope)
        Sets the (optional) JavaScript scope
        Parameters:
        scope - The JavaScript scope

      • getJsMode

        @Nullable
public Boolean getJsMode()
        Gets the (optional) JavaScript mode
        Returns:
        The JavaScript mode
        Since:
        2.13

      • setJsMode

        public void setJsMode​(@Nullable
                      Boolean jsMode)
        Sets the (optional) JavaScript Mode
        Parameters:
        jsMode - Specifies whether to convert intermediate data into BSON format between the execution of the map and reduce functions
        Since:
        2.13

      • getOutputDB

        @Nullable
public String getOutputDB()
        Gets the (optional) database name where the output collection should reside
        Returns:
        the name of the database the result is stored in, or null.

      • setOutputDB

        public void setOutputDB​(@Nullable
                        String outputDB)
        Sets the (optional) database name where the output collection should reside
        Parameters:
        outputDB - the name of the database to send the Map Reduce output to

      • getBypassDocumentValidation

        @Nullable
public Boolean getBypassDocumentValidation()
        Gets whether to bypass document validation, or null if unspecified. The default is null.
        Returns:
        whether to bypass document validation, or null if unspecified.
        Since:
        2.14
        Since server release
        3.2

      • setBypassDocumentValidation

        public void setBypassDocumentValidation​(@Nullable
                                        Boolean bypassDocumentValidation)
        Sets whether to bypass document validation.
        Parameters:
        bypassDocumentValidation - whether to bypass document validation, or null if unspecified
        Since:
        2.14
        Since server release
        3.2

      • toDBObject

        public DBObject toDBObject()
        Turns this command into a DBObject representation of this map reduce command.
        Returns:
        a DBObject that contains the MongoDB document representation of this command.

      • setReadPreference

        public void setReadPreference​(@Nullable
                              ReadPreference preference)
        Sets the read preference for this command. See the * documentation for ReadPreference for more information.
        Parameters:
        preference - Read Preference to use

      • getReadPreference

        @Nullable
public ReadPreference getReadPreference()
        Gets the read preference
        Returns:
        the readPreference

      • getCollation

        @Nullable
public Collation getCollation()
        Returns the collation
        Returns:
        the collation
        Since:
        3.4
        Since server release
        3.4

      • setCollation

        @Nullable
public void setCollation​(Collation collation)
        Sets the collation options
        Parameters:
        collation - the collation options
        Since:
        3.4
        Since server release
        3.4