/**
* This software is licensed to you under the Apache License, Version 2.0 (the
* "Apache License").
*
* LinkedIn's contributions are made under the Apache License. If you contribute
* to the Software, the contributions will be deemed to have been made under the
* Apache License, unless you expressly indicate otherwise. Please do not make any
* contributions that would be inconsistent with the Apache License.
*
* You may obtain a copy of the Apache License at http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, this software
* distributed under the Apache License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the Apache
* License for the specific language governing permissions and limitations for the
* software governed under the Apache License.
*
* © 2012 LinkedIn Corp. All Rights Reserved.
*/
package com.senseidb.search.req.mapred.functions;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;
import com.senseidb.search.req.mapred.CombinerStage;
import com.senseidb.search.req.mapred.FacetCountAccessor;
import com.senseidb.search.req.mapred.FieldAccessor;
import com.senseidb.search.req.mapred.SenseiMapReduce;
import org.jboss.netty.util.internal.ConcurrentHashMap;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.senseidb.util.JSONUtil.FastJSONArray;
import com.senseidb.util.JSONUtil.FastJSONObject;
@SuppressWarnings("unchecked")
public class CountGroupByMapReduce implements SenseiMapReduce<HashMap<String, IntContainer>, ArrayList<GroupedValue>> {
private static final long serialVersionUID = 1L;
private String[] columns;
public void init(JSONObject params) {
try {
JSONArray columnsJson = params.getJSONArray("columns");
columns = new String[columnsJson.length()];
for (int i = 0; i < columnsJson.length(); i++) {
columns[i] = columnsJson.getString(i);
}
} catch (JSONException ex) {
throw new RuntimeException(ex);
}
}
public HashMap<String, IntContainer> map(int[] docIds, int docIdCount, long[] uids, FieldAccessor accessor, FacetCountAccessor facetCountAccessor) {
HashMap<String, IntContainer> ret = new HashMap<String, IntContainer>();
int duplicatedUids = 0;
for (int i = 0; i < docIdCount; i++) {
String key = getKey(columns, accessor, docIds[i]);
IntContainer count = ret.get(key);
if (!ret.containsKey(key)) {
ret.put(key, new IntContainer(1));
} else {
count.add(1);
}
}
return ret;
}
private String getKey(String[] columns, FieldAccessor fieldAccessor, int docId) {
StringBuilder key = new StringBuilder(fieldAccessor.get(columns[0], docId).toString());
for (int i = 1; i < columns.length; i++) {
key.append(":").append(fieldAccessor.get(columns[i], docId).toString());
}
return key.toString();
}
@Override
public List<HashMap<String, IntContainer>> combine(List<HashMap<String, IntContainer>> mapResults, CombinerStage combinerStage) {
if (mapResults == null || mapResults.isEmpty()) return mapResults;
HashMap<String, IntContainer> ret = new HashMap<String, IntContainer>();
for (int i = 0; i < mapResults.size(); i++) {
Map<String, IntContainer> map = mapResults.get(i);
for (String key : map.keySet()) {
IntContainer count = ret.get(key);
if (count != null) {
count.add(map.get(key).value);
} else {
ret.put(key, map.get(key));
}
}
}
return java.util.Arrays.asList(ret);
}
@Override
public ArrayList<GroupedValue> reduce(List<HashMap<String, IntContainer>> combineResults) {
if (combineResults == null || combineResults.isEmpty()) return new ArrayList<GroupedValue>();
Map<String, IntContainer> retMap = new HashMap<String, IntContainer>();
for (int i = 0; i < combineResults.size(); i++) {
Map<String, IntContainer> map = combineResults.get(i);
for (String key : map.keySet()) {
IntContainer count = retMap.get(key);
if (count != null) {
count.add(map.get(key).value);
} else {
retMap.put(key, map.get(key));
}
}
}
ArrayList<GroupedValue> ret = new ArrayList<GroupedValue>();
for (Map.Entry<String, IntContainer> entry : retMap.entrySet()) {
ret.add(new GroupedValue(entry.getKey(), entry.getValue().value));
}
Collections.sort(ret);
return ret;
}
public JSONObject render(ArrayList<GroupedValue> reduceResult) {
try {
List<JSONObject> ret = new ArrayList<JSONObject>();
for (GroupedValue grouped : reduceResult) {
ret.add(new FastJSONObject().put(grouped.key, grouped.value));
}
return new FastJSONObject().put("groupedCounts", new FastJSONArray(ret));
} catch (JSONException ex) {
throw new RuntimeException(ex);
}
}
@Override
public String[] getColumns() {
return columns;
}
}
class GroupedValue implements Comparable {
String key;
int value;
public GroupedValue(String key, int value) {
super();
this.key = key;
this.value = value;
}
@Override
public int compareTo(Object o) {
return ((GroupedValue) o).value - value;
}
@Override
public String toString() {
return key + ", count=" + value;
}
}