Java tutorial
/** * This file is part of Graylog. * * Graylog is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Graylog is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Graylog. If not, see <http://www.gnu.org/licenses/>. */ package integration.util.mongodb; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.ObjectMapper; import com.google.common.collect.Lists; import com.mongodb.BasicDBObject; import com.mongodb.DBObject; import com.mongodb.util.JSON; import java.io.File; import java.io.IOException; import java.net.URL; import java.util.HashMap; import java.util.List; import java.util.Map; public class JsonReader implements DumpReader { private final Map<String, List<DBObject>> collectionMap = new HashMap<>(); public JsonReader(URL location) throws IOException { final File file = new File(location.getPath()); final ObjectMapper mapper = new ObjectMapper(); final TypeReference ref = new TypeReference<Map<String, List<Map<String, Object>>>>() { }; final Map<String, List<Map<String, Object>>> rawMap = mapper.readValue(file, ref); for (Map.Entry<String, List<Map<String, Object>>> entry : rawMap.entrySet()) { if (!collectionMap.containsKey(entry.getKey())) collectionMap.put(entry.getKey(), Lists.<DBObject>newArrayList()); for (Map<String, Object> rawDoc : entry.getValue()) { final BasicDBObject dbObject = (BasicDBObject) JSON.parse(mapper.writeValueAsString(rawDoc)); collectionMap.get(entry.getKey()).add(dbObject); } } } public Map<String, List<DBObject>> toMap() { return collectionMap; } }