Example usage for com.mongodb MapReduceOutput results

Introduction

In this page you can find the example usage for com.mongodb MapReduceOutput results.

Prototype

@SuppressWarnings("unchecked")
public Iterable<DBObject> results()

Source Link

Document

Returns an iterable containing the results of the operation.

Usage

From source file:org.springframework.data.mongodb.core.MongoTemplate.java

License:Apache License

public <T> MapReduceResults<T> mapReduce(Query query, String inputCollectionName, String mapFunction,
        String reduceFunction, MapReduceOptions mapReduceOptions, Class<T> entityClass) {

    String mapFunc = replaceWithResourceIfNecessary(mapFunction);
    String reduceFunc = replaceWithResourceIfNecessary(reduceFunction);
    DBCollection inputCollection = getCollection(inputCollectionName);

    MapReduceCommand command = new MapReduceCommand(inputCollection, mapFunc, reduceFunc,
            mapReduceOptions.getOutputCollection(), mapReduceOptions.getOutputType(),
            query == null || query.getQueryObject() == null ? null
                    : queryMapper.getMappedObject(query.getQueryObject(), null));

    copyMapReduceOptionsToCommand(query, mapReduceOptions, command);

    if (LOGGER.isDebugEnabled()) {
        LOGGER.debug("Executing MapReduce on collection [{}], mapFunction [{}], reduceFunction [{}]",
                command.getInput(), mapFunc, reduceFunc);
    }//from   w  w  w.j  a  v  a  2 s . com

    MapReduceOutput mapReduceOutput = inputCollection.mapReduce(command);

    if (LOGGER.isDebugEnabled()) {
        LOGGER.debug("MapReduce command result = [{}]", serializeToJsonSafely(mapReduceOutput.results()));
    }

    List<T> mappedResults = new ArrayList<T>();
    DbObjectCallback<T> callback = new ReadDbObjectCallback<T>(mongoConverter, entityClass,
            inputCollectionName);

    for (DBObject dbObject : mapReduceOutput.results()) {
        mappedResults.add(callback.doWith(dbObject));
    }

    return new MapReduceResults<T>(mappedResults, mapReduceOutput);
}