/*
 * Copyright 2008-present MongoDB, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
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package com.mongodb.client;

import com.mongodb.client.model.Collation;
import com.mongodb.client.model.MapReduceAction;
import com.mongodb.lang.Nullable;
import org.bson.conversions.Bson;

import java.util.concurrent.TimeUnit;

Iterable for map-reduce.

By default the MapReduceIterable returns the results inline. You can write map-reduce output to a collection by using the collectionName(String) method.

Type parameters:
  • <TResult> – The type of the result.
Since:3.0
/** * Iterable for map-reduce. * * <p>By default the {@code MapReduceIterable} returns the results inline. You can write map-reduce output to a collection by using the * {@link MapReduceIterable#collectionName(String)} method.</p> * * @param <TResult> The type of the result. * @since 3.0 */
public interface MapReduceIterable<TResult> extends MongoIterable<TResult> {
Aggregates documents to a collection according to the specified map-reduce function with the given options, which must specify a non-inline result.
Throws:
  • IllegalStateException – if a collection name to write the results to has not been specified
See Also:
Since:3.4
/** * Aggregates documents to a collection according to the specified map-reduce function with the given options, which must specify a * non-inline result. * * @throws IllegalStateException if a collection name to write the results to has not been specified * @see #collectionName(String) * @since 3.4 */
void toCollection();
Sets the collectionName for the output of the MapReduce

The default action is replace the collection if it exists, to change this use action.

Params:
  • collectionName – the name of the collection that you want the map-reduce operation to write its output.
Returns:this
/** * Sets the collectionName for the output of the MapReduce * * <p>The default action is replace the collection if it exists, to change this use {@link #action}.</p> * * @param collectionName the name of the collection that you want the map-reduce operation to write its output. * @return this */
MapReduceIterable<TResult> collectionName(String collectionName);
Sets the JavaScript function that follows the reduce method and modifies the output.
Params:
  • finalizeFunction – the JavaScript function that follows the reduce method and modifies the output.
Returns:this
@mongodb.driver.manualreference/command/mapReduce/#mapreduce-finalize-cmd Requirements for the finalize Function
/** * Sets the JavaScript function that follows the reduce method and modifies the output. * * @param finalizeFunction the JavaScript function that follows the reduce method and modifies the output. * @return this * @mongodb.driver.manual reference/command/mapReduce/#mapreduce-finalize-cmd Requirements for the finalize Function */
MapReduceIterable<TResult> finalizeFunction(@Nullable String finalizeFunction);
Sets the global variables that are accessible in the map, reduce and finalize functions.
Params:
  • scope – the global variables that are accessible in the map, reduce and finalize functions.
Returns:this
@mongodb.driver.manualreference/command/mapReduce mapReduce
/** * Sets the global variables that are accessible in the map, reduce and finalize functions. * * @param scope the global variables that are accessible in the map, reduce and finalize functions. * @return this * @mongodb.driver.manual reference/command/mapReduce mapReduce */
MapReduceIterable<TResult> scope(@Nullable Bson scope);
Sets the sort criteria to apply to the query.
Params:
  • sort – the sort criteria, which may be null.
Returns:this
@mongodb.driver.manualreference/method/cursor.sort/ Sort
/** * Sets the sort criteria to apply to the query. * * @param sort the sort criteria, which may be null. * @return this * @mongodb.driver.manual reference/method/cursor.sort/ Sort */
MapReduceIterable<TResult> sort(@Nullable Bson sort);
Sets the query filter to apply to the query.
Params:
  • filter – the filter to apply to the query.
Returns:this
@mongodb.driver.manualreference/method/db.collection.find/ Filter
/** * Sets the query filter to apply to the query. * * @param filter the filter to apply to the query. * @return this * @mongodb.driver.manual reference/method/db.collection.find/ Filter */
MapReduceIterable<TResult> filter(@Nullable Bson filter);
Sets the limit to apply.
Params:
  • limit – the limit, which may be null
Returns:this
@mongodb.driver.manualreference/method/cursor.limit/#cursor.limit Limit
/** * Sets the limit to apply. * * @param limit the limit, which may be null * @return this * @mongodb.driver.manual reference/method/cursor.limit/#cursor.limit Limit */
MapReduceIterable<TResult> limit(int limit);
Sets the flag that specifies whether to convert intermediate data into BSON format between the execution of the map and reduce functions. Defaults to false.
Params:
  • jsMode – the flag that specifies whether to convert intermediate data into BSON format between the execution of the map and reduce functions
Returns:jsMode
@mongodb.driver.manualreference/command/mapReduce mapReduce
/** * Sets the flag that specifies whether to convert intermediate data into BSON format between the execution of the map and reduce * functions. Defaults to false. * * @param jsMode the flag that specifies whether to convert intermediate data into BSON format between the execution of the map and * reduce functions * @return jsMode * @mongodb.driver.manual reference/command/mapReduce mapReduce */
MapReduceIterable<TResult> jsMode(boolean jsMode);
Sets whether to include the timing information in the result information.
Params:
  • verbose – whether to include the timing information in the result information.
Returns:this
/** * Sets whether to include the timing information in the result information. * * @param verbose whether to include the timing information in the result information. * @return this */
MapReduceIterable<TResult> verbose(boolean verbose);
Sets the maximum execution time on the server for this operation.
Params:
  • maxTime – the max time
  • timeUnit – the time unit, which may not be null
Returns:this
@mongodb.driver.manualreference/method/cursor.maxTimeMS/#cursor.maxTimeMS Max Time
/** * Sets the maximum execution time on the server for this operation. * * @param maxTime the max time * @param timeUnit the time unit, which may not be null * @return this * @mongodb.driver.manual reference/method/cursor.maxTimeMS/#cursor.maxTimeMS Max Time */
MapReduceIterable<TResult> maxTime(long maxTime, TimeUnit timeUnit);
Specify the MapReduceAction to be used when writing to a collection.
Params:
Returns:this
/** * Specify the {@code MapReduceAction} to be used when writing to a collection. * * @param action an {@link MapReduceAction} to perform on the collection * @return this */
MapReduceIterable<TResult> action(MapReduceAction action);
Sets the name of the database to output into.
Params:
  • databaseName – the name of the database to output into.
Returns:this
@mongodb.driver.manualreference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
/** * Sets the name of the database to output into. * * @param databaseName the name of the database to output into. * @return this * @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action */
MapReduceIterable<TResult> databaseName(@Nullable String databaseName);
Sets if the output database is sharded
Params:
  • sharded – if the output database is sharded
Returns:this
@mongodb.driver.manualreference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
/** * Sets if the output database is sharded * * @param sharded if the output database is sharded * @return this * @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action */
MapReduceIterable<TResult> sharded(boolean sharded);
Sets if the post-processing step will prevent MongoDB from locking the database. Valid only with the MapReduceAction.MERGE or MapReduceAction.REDUCE actions.
Params:
  • nonAtomic – if the post-processing step will prevent MongoDB from locking the database.
Returns:this
@mongodb.driver.manualreference/command/mapReduce/#output-to-a-collection-with-an-action output with an action
/** * Sets if the post-processing step will prevent MongoDB from locking the database. * * Valid only with the {@code MapReduceAction.MERGE} or {@code MapReduceAction.REDUCE} actions. * * @param nonAtomic if the post-processing step will prevent MongoDB from locking the database. * @return this * @mongodb.driver.manual reference/command/mapReduce/#output-to-a-collection-with-an-action output with an action */
MapReduceIterable<TResult> nonAtomic(boolean nonAtomic);
Sets the number of documents to return per batch.
Params:
  • batchSize – the batch size
Returns:this
@mongodb.driver.manualreference/method/cursor.batchSize/#cursor.batchSize Batch Size
/** * Sets the number of documents to return per batch. * * @param batchSize the batch size * @return this * @mongodb.driver.manual reference/method/cursor.batchSize/#cursor.batchSize Batch Size */
@Override MapReduceIterable<TResult> batchSize(int batchSize);
Sets the bypass document level validation flag.

Note: This only applies when an $out stage is specified

.
Params:
  • bypassDocumentValidation – If true, allows the write to opt-out of document level validation.
Returns:this
Since:3.2
@mongodb.driver.manualreference/command/mapReduce mapReduce
@mongodb.server.release3.2
/** * Sets the bypass document level validation flag. * * <p>Note: This only applies when an $out stage is specified</p>. * * @param bypassDocumentValidation If true, allows the write to opt-out of document level validation. * @return this * @since 3.2 * @mongodb.driver.manual reference/command/mapReduce mapReduce * @mongodb.server.release 3.2 */
MapReduceIterable<TResult> bypassDocumentValidation(@Nullable Boolean bypassDocumentValidation);
Sets the collation options

A null value represents the server default.

Params:
  • collation – the collation options to use
Returns:this
Since:3.4
@mongodb.server.release3.4
/** * Sets the collation options * * <p>A null value represents the server default.</p> * @param collation the collation options to use * @return this * @since 3.4 * @mongodb.server.release 3.4 */
MapReduceIterable<TResult> collation(@Nullable Collation collation); }