Github user vrozov commented on a diff in the pull request: https://github.com/apache/drill/pull/1110#discussion_r167625240 --- Diff: exec/java-exec/src/main/java/org/apache/drill/exec/physical/config/OrderedMuxExchange.java --- @@ -0,0 +1,64 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF 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 org.apache.drill.exec.physical.config; + +import java.util.List; + +import org.apache.drill.exec.physical.MinorFragmentEndpoint; +import org.apache.drill.exec.physical.base.PhysicalOperator; +import org.apache.drill.exec.physical.base.Receiver; +import org.apache.drill.common.logical.data.Order.Ordering; +import com.fasterxml.jackson.annotation.JsonProperty; +import com.fasterxml.jackson.annotation.JsonTypeName; + +/** + * OrderedMuxExchange is a version of MuxExchange where the incoming batches are sorted + * merge operation is performed to produced a sorted stream as output. + */ +@JsonTypeName("ordered-mux-exchange") +public class OrderedMuxExchange extends AbstractMuxExchange { + private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(OrderedMuxExchange.class); + + private final List<Ordering> orderings; + + public OrderedMuxExchange(@JsonProperty("child") PhysicalOperator child, @JsonProperty("orderings")List<Ordering> orderings) { + super(child); + this.orderings = orderings; + } + + @Override + public Receiver getReceiver(int minorFragmentId) { + createSenderReceiverMapping(); --- End diff -- Consider moving this functionality to the parent class and keep only creating an instance of concrete `MergingReceiver` in the subclass.
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