fe/src/main/java/org/apache/impala/planner/PlanRootSink.java

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//   http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.impala.planner;

import org.apache.impala.thrift.TDataSink;
import org.apache.impala.thrift.TDataSinkType;
import org.apache.impala.thrift.TExplainLevel;
import org.apache.impala.thrift.TQueryOptions;

/**
 * Sink for the root of a query plan that produces result rows. Allows coordination
 * between the sender which produces those rows, and the consumer which sends them to the
 * client, despite both executing concurrently.
 */
public class PlanRootSink extends DataSink {

  public void appendSinkExplainString(String prefix, String detailPrefix,
      TQueryOptions queryOptions, TExplainLevel explainLevel, StringBuilder output) {
    output.append(String.format("%sPLAN-ROOT SINK\n", prefix));
  }

  @Override
  public void computeResourceProfile(TQueryOptions queryOptions) {
    // TODO: add a memory estimate
    resourceProfile_ = ResourceProfile.noReservation(0);
  }

  protected TDataSink toThrift() {
    return new TDataSink(TDataSinkType.PLAN_ROOT_SINK);
  }
}