/** * Copyright 2017 Confluent 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 io.confluent.ksql.function.udaf.count; import org.apache.kafka.connect.data.Schema; import org.apache.kafka.streams.kstream.Merger; import java.util.Collections; import java.util.List; import java.util.Map; import io.confluent.ksql.function.KsqlAggregateFunction; import io.confluent.ksql.parser.tree.Expression; public class CountKudaf extends KsqlAggregateFunction<Object, Long> { CountKudaf(int argIndexInValue) { super(argIndexInValue, () -> 0L, Schema.INT64_SCHEMA, Collections.singletonList(Schema.FLOAT64_SCHEMA) ); } @Override public Long aggregate(Object currentVal, Long currentAggVal) { return currentAggVal + 1; } @Override public Merger<String, Long> getMerger() { return (aggKey, aggOne, aggTwo) -> aggOne + aggTwo; } @Override public KsqlAggregateFunction<Object, Long> getInstance(Map<String, Integer> expressionNames, List<Expression> functionArguments) { int udafIndex = expressionNames.get(functionArguments.get(0).toString()); return new CountKudaf(udafIndex); } @Override public boolean hasSameArgTypes(List<Schema> argTypeList) { return false; } }