/*
 * 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
 * limitations under the License.
 */

package com.mongodb.client.model;



The map reduce to collection actions.
These actions are only available when passing out a collection that already exists. This option is not available on secondary members
of replica sets.  The Enum values dictate what to do with the output collection if it already exists when the map reduce is run.
Since:
3.0
@mongodb.driver.manual
reference/command/mapReduce/ mapReduce Command
@mongodb.driver.manual
core/map-reduce/ mapReduce Overview/**
 * The map reduce to collection actions.
 *
 * <p>These actions are only available when passing out a collection that already exists. This option is not available on secondary members
 * of replica sets.  The Enum values dictate what to do with the output collection if it already exists when the map reduce is run.</p>
 *
 * @since 3.0
 * @mongodb.driver.manual reference/command/mapReduce/ mapReduce Command
 * @mongodb.driver.manual core/map-reduce/ mapReduce Overview
 */
public enum MapReduceAction {
    
Replace the contents of the collectionName if the collection with the collectionName exists. /**
     * Replace the contents of the {@code collectionName} if the collection with the {@code collectionName} exists.
     */
    REPLACE("replace"),

    
Merge the new result with the existing result if the output collection already exists. If an existing document has the same key
as the new result, overwrite that existing document.
/**
     * Merge the new result with the existing result if the output collection already exists. If an existing document has the same key
     * as the new result, overwrite that existing document.
     */
    MERGE("merge"),

    
Merge the new result with the existing result if the output collection already exists. If an existing document has the same key
as the new result, apply the reduce function to both the new and the existing documents and overwrite the existing document with
the result.
/**
     * Merge the new result with the existing result if the output collection already exists. If an existing document has the same key
     * as the new result, apply the reduce function to both the new and the existing documents and overwrite the existing document with
     * the result.
     */
    REDUCE("reduce");

    private final String value;

    MapReduceAction(final String value) {
        this.value = value;
    }

    
Returns:
the String representation of this Action that the MongoDB server understands/**
     * @return the String representation of this Action that the MongoDB server understands
     */
    public String getValue() {
        return value;
    }
}