andresgomezfrr commented on a change in pull request #5789: Add stringLast and stringFirst aggregators extension URL: https://github.com/apache/incubator-druid/pull/5789#discussion_r205747961
########## File path: processing/src/main/java/io/druid/query/aggregation/first/StringFirstAggregator.java ########## @@ -0,0 +1,106 @@ +/* + * Licensed to Metamarkets Group Inc. (Metamarkets) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. Metamarkets licenses this file + * to you 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 io.druid.query.aggregation.first; + +import io.druid.java.util.common.ISE; +import io.druid.query.aggregation.Aggregator; +import io.druid.query.aggregation.SerializablePairLongString; +import io.druid.segment.BaseLongColumnValueSelector; +import io.druid.segment.BaseObjectColumnValueSelector; + +public class StringFirstAggregator implements Aggregator +{ + + private final BaseObjectColumnValueSelector valueSelector; + private final BaseLongColumnValueSelector timeSelector; + private final int maxStringBytes; + + protected long firstTime; + protected String firstValue; + + public StringFirstAggregator( + BaseLongColumnValueSelector timeSelector, + BaseObjectColumnValueSelector valueSelector, + int maxStringBytes + ) + { + this.valueSelector = valueSelector; + this.timeSelector = timeSelector; + this.maxStringBytes = maxStringBytes; + + firstTime = Long.MAX_VALUE; + firstValue = null; + } + + @Override + public void aggregate() + { + long time = timeSelector.getLong(); + if (time < firstTime) { + firstTime = time; + Object value = valueSelector.getObject(); Review comment: :+1: ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@druid.apache.org For additional commands, e-mail: commits-h...@druid.apache.org
