/*
* Copyright 2011-2017 the original author or authors.
*
* 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 org.springframework.data.mongodb.core.mapreduce;
import java.util.Iterator;
import java.util.List;
import org.bson.Document;
import org.springframework.util.Assert;
import com.mongodb.MapReduceOutput;
/**
* Collects the results of performing a MapReduce operations.
*
* @author Mark Pollack
* @author Oliver Gierke
* @author Christoph Strobl
* @author Mark Paluch
* @param <T> The class in which the results are mapped onto, accessible via an iterator.
*/
public class MapReduceResults<T> implements Iterable<T> {
private final List<T> mappedResults;
private final Document rawResults;
private final String outputCollection;
private final MapReduceTiming mapReduceTiming;
private final MapReduceCounts mapReduceCounts;
/**
* Creates a new {@link MapReduceResults} from the given mapped results and the raw one.
*
* @param mappedResults must not be {@literal null}.
* @param rawResults must not be {@literal null}.
* @deprecated since 1.7. Please use {@link #MapReduceResults(List, MapReduceOutput)}
*/
@Deprecated
public MapReduceResults(List<T> mappedResults, Document rawResults) {
Assert.notNull(mappedResults, "List of mapped results must not be null!");
Assert.notNull(rawResults, "Raw results must not be null!");
this.mappedResults = mappedResults;
this.rawResults = rawResults;
this.mapReduceTiming = parseTiming(rawResults);
this.mapReduceCounts = parseCounts(rawResults);
this.outputCollection = parseOutputCollection(rawResults);
}
/**
* Creates a new {@link MapReduceResults} from the given mapped results and the {@link MapReduceOutput}.
*
* @param mappedResults must not be {@literal null}.
* @param mapReduceOutput must not be {@literal null}.
* @since 1.7
*/
public MapReduceResults(List<T> mappedResults, MapReduceOutput mapReduceOutput) {
Assert.notNull(mappedResults, "MappedResults must not be null!");
Assert.notNull(mapReduceOutput, "MapReduceOutput must not be null!");
this.mappedResults = mappedResults;
this.rawResults = null;
this.mapReduceTiming = parseTiming(mapReduceOutput);
this.mapReduceCounts = parseCounts(mapReduceOutput);
this.outputCollection = parseOutputCollection(mapReduceOutput);
}
/*
* (non-Javadoc)
* @see java.lang.Iterable#iterator()
*/
public Iterator<T> iterator() {
return mappedResults.iterator();
}
public MapReduceTiming getTiming() {
return mapReduceTiming;
}
public MapReduceCounts getCounts() {
return mapReduceCounts;
}
public String getOutputCollection() {
return outputCollection;
}
public Document getRawResults() {
return rawResults;
}
private static MapReduceTiming parseTiming(Document rawResults) {
Document timing = (Document) rawResults.get("timing");
if (timing == null) {
return new MapReduceTiming(-1, -1, -1);
}
if (timing.get("mapTime") != null && timing.get("emitLoop") != null && timing.get("total") != null) {
return new MapReduceTiming(getAsLong(timing, "mapTime"), getAsLong(timing, "emitLoop"),
getAsLong(timing, "total"));
}
return new MapReduceTiming(-1, -1, -1);
}
/**
* Returns the value of the source's field with the given key as {@link Long}.
*
* @param source
* @param key
* @return
*/
private static Long getAsLong(Document source, String key) {
Object raw = source.get(key);
return raw instanceof Long ? (Long) raw : (Integer) raw;
}
/**
* Parses the raw {@link Document} result into a {@link MapReduceCounts} value object.
*
* @param rawResults
* @return
*/
private static MapReduceCounts parseCounts(Document rawResults) {
Document counts = (Document) rawResults.get("counts");
if (counts == null) {
return MapReduceCounts.NONE;
}
if (counts.get("input") != null && counts.get("emit") != null && counts.get("output") != null) {
return new MapReduceCounts(getAsLong(counts, "input"), getAsLong(counts, "emit"), getAsLong(counts, "output"));
}
return MapReduceCounts.NONE;
}
/**
* Parses the output collection from the raw {@link Document} result.
*
* @param rawResults
* @return
*/
private static String parseOutputCollection(Document rawResults) {
Object resultField = rawResults.get("result");
if (resultField == null) {
return null;
}
return resultField instanceof Document ? ((Document) resultField).get("collection").toString()
: resultField.toString();
}
private static MapReduceCounts parseCounts(final MapReduceOutput mapReduceOutput) {
return new MapReduceCounts(mapReduceOutput.getInputCount(), mapReduceOutput.getEmitCount(),
mapReduceOutput.getOutputCount());
}
private static String parseOutputCollection(final MapReduceOutput mapReduceOutput) {
return mapReduceOutput.getCollectionName();
}
private static MapReduceTiming parseTiming(MapReduceOutput mapReduceOutput) {
return new MapReduceTiming(-1, -1, mapReduceOutput.getDuration());
}
}