Java tutorial
/* * Copyright 2012 Nodeable 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.streamreduce.core.dao; import com.google.code.morphia.Datastore; import com.google.code.morphia.Key; import com.mongodb.BasicDBObject; import com.mongodb.DB; import com.mongodb.DBCollection; import com.mongodb.DBObject; import com.mongodb.WriteConcern; import com.streamreduce.core.model.Metric; import org.bson.types.ObjectId; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.stereotype.Repository; import java.util.List; import java.util.Map; @Repository("metricDAO") public class MetricDAO extends ValidatingDAO<Metric> { private Datastore messageDatastore; @Autowired protected MetricDAO(@Qualifier(value = "messageDBDatastore") Datastore datastore) { super(datastore); this.messageDatastore = datastore; } /** * Returns a list of metrics. * * @param accountId the account the metrics should be queried from * @param metricName the metric name * @param criteria the metric criteria * @param granularity the metric granularity * @param startTime the time of the earliest entry to return (Should be null if it doesn't matter) * @param endTime the time of the latest entry to return (Should be null if it doesn't matter) * @param pageNum the "page" number * @param pageSize the number of items metrics page * * @return list of metrics */ public List<DBObject> getMetrics(String accountId, String metricName, Map<String, List<String>> criteria, Long granularity, Long startTime, Long endTime, int pageNum, int pageSize) { DB db = messageDatastore.getDB(); DBCollection collection = db.getCollection("Metric_" + accountId); BasicDBObject query = new BasicDBObject(); query.put("metricName", metricName); query.put("granularity", granularity); for (Map.Entry<String, List<String>> criteriaEntry : criteria.entrySet()) { String criteriaName = criteriaEntry.getKey(); List<String> criteriaValue = criteriaEntry.getValue(); String queryKey = "metricCriteria." + criteriaName; if (criteriaValue.size() == 1) { String value = criteriaValue.get(0); if (value.equals("*")) { // Criteria is a wildcard so return metrics that have the metric criteria query.put(queryKey, new BasicDBObject("$exists", true)); } else { // Criteria is an explicit value query.put(queryKey, value); } } else { // Criteria is an array/list of values query.put(queryKey, new BasicDBObject("$in", criteriaValue)); } } if (startTime != null || endTime != null) { BasicDBObject timestampQuery = new BasicDBObject(); if (startTime != null) { timestampQuery.put("$gte", startTime); } if (endTime != null) { timestampQuery.put("$lte", endTime); } query.put("metricTimestamp", timestampQuery); } return collection.find(query).sort(new BasicDBObject("metricTimestamp", -1)).skip((pageNum - 1) * pageSize) .limit(pageSize).toArray(); } @Override public Key<Metric> save(Metric entity) { DBCollection collection = getCollection(entity.getAccountId()); DBObject dbObject = entity.toDBObject(); collection.save(dbObject); entity.setId((ObjectId) dbObject.get("_id")); return new Key<>(Metric.class, entity.getId()); } @Override public Key<Metric> save(Metric entity, WriteConcern wc) { DBCollection collection = getCollection(entity.getAccountId()); DBObject dbObject = entity.toDBObject(); collection.save(dbObject, wc); entity.setId((ObjectId) dbObject.get("_id")); return new Key<>(Metric.class, entity.getId()); } public Metric get(ObjectId id, String accountId) { DBCollection collection = getCollection(accountId); BasicDBObject result = (BasicDBObject) collection.findOne(new BasicDBObject("_id", id)); return new Metric(result); } private DBCollection getCollection(String accountId) { DB db = getDatastore().getDB(); return db.getCollection("Metric_" + accountId); } }