//Copyright 2012 Joe McTee
//
// 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.jeklsoft.cassandraclient.hector;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import org.apache.log4j.Logger;
import org.joda.time.DateTime;
import org.joda.time.Interval;
import com.jeklsoft.cassandraclient.Reading;
import com.jeklsoft.cassandraclient.ReadingsPersistor;
import me.prettyprint.cassandra.serializers.BigIntegerSerializer;
import me.prettyprint.cassandra.serializers.UUIDSerializer;
import me.prettyprint.hector.api.Keyspace;
import me.prettyprint.hector.api.Serializer;
import me.prettyprint.hector.api.beans.ColumnSlice;
import me.prettyprint.hector.api.beans.HColumn;
import me.prettyprint.hector.api.factory.HFactory;
import me.prettyprint.hector.api.mutation.Mutator;
import me.prettyprint.hector.api.query.QueryResult;
import me.prettyprint.hector.api.query.SliceQuery;
/*
Cluster: SensorNet
Keyspace: "Climate" {
CF: "Sensors" {
sensor_uuid: {
<timestamp: DateTime> : reading<ReadingBuffer>
...
<timestamp: DateTime> : reading<ReadingBuffer>
}
...
sensor_uuid: {
<timestamp: DateTime> : reading<ReadingBuffer>
...
<timestamp: DateTime> : reading<ReadingBuffer>
}
}
}
*/
public class HectorProtocolBufferWithStandardColumnExample implements ReadingsPersistor {
private static final Logger log = Logger.getLogger(HectorProtocolBufferWithStandardColumnExample.class);
private static final Serializer genericOutputSerializer = ExtendedTypeInferringSerializer.get();
private static final Serializer us = UUIDSerializer.get();
private static final Serializer ds = DateTimeSerializer.get();
private static final Serializer rs = ReadingSerializer.get();
private final Keyspace keyspace;
private final String columnFamilyName;
private final int ttl = 365 * 24 * 60 * 60; // 1 year in seconds
public HectorProtocolBufferWithStandardColumnExample(Keyspace keyspace, String columnFamilyName) {
this.keyspace = keyspace;
this.columnFamilyName = columnFamilyName;
ExtensibleTypeInferringSerializer.addSerializer(BigInteger.class, BigIntegerSerializer.get());
ExtensibleTypeInferringSerializer.addSerializer(DateTime.class, DateTimeSerializer.get());
ExtensibleTypeInferringSerializer.addSerializer(BigDecimal.class, BigDecimalSerializer.get());
ExtensibleTypeInferringSerializer.addSerializer(Reading.class, ReadingSerializer.get());
}
@Override
public void addReadings(final List<Reading> readings) {
Mutator mutator = HFactory.createMutator(keyspace, genericOutputSerializer);
for (Reading reading : readings) {
HColumn column = HFactory.createColumn(reading.getTimestamp(),
reading,
genericOutputSerializer,
genericOutputSerializer).setTtl(ttl);
mutator.addInsertion(reading.getSensorId(), columnFamilyName, column);
}
mutator.execute();
}
@Override
public List<Reading> querySensorReadingsByInterval(UUID sensorId, Interval interval, int maxToReturn) {
SliceQuery<UUID, DateTime, Reading> query = HFactory.createSliceQuery(keyspace, us, ds, rs);
query.setColumnFamily(columnFamilyName)
.setKey(sensorId)
.setRange(new DateTime(interval.getStartMillis()), new DateTime(interval.getEndMillis()), false, maxToReturn);
QueryResult<ColumnSlice<DateTime, Reading>> result = query.execute();
List<HColumn<DateTime, Reading>> columns = result.get().getColumns();
List<Reading> readings = new ArrayList<Reading>();
for (HColumn column : columns) {
DateTime timestamp = (DateTime) column.getName();
Reading reading = new Reading(sensorId, timestamp, (Reading) column.getValue());
readings.add(reading);
}
return readings;
}
}