io.druid.query.monomorphicprocessing.HotLoopCallee Maven / Gradle / Ivy

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 * to you under the Apache License, Version 2.0 (the
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 *
 * http://www.apache.org/licenses/LICENSE-2.0
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 * Unless required by applicable law or agreed to in writing,
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package io.druid.query.monomorphicprocessing;

/**
 * Marker interface for abstractions, which are called from hot loops during query processing. Some of the methods of
 * interfaces extending HotLoopCallee should be annotated with {@link CalledFromHotLoop}.
 */
public interface HotLoopCallee
{
  /**
   * Implementations of this method should call {@code inspector.visit()} with all fields of this class, which meet two
   * conditions:
   *  1. They are used in methods of this class, annotated with {@link CalledFromHotLoop}
   *  2. They are either:
   *     a. Nullable objects
   *     b. Instances of HotLoopCallee
   *     c. Objects, which don't always have a specific class in runtime. For example, a field of type {@link
   *        java.util.Set} could be {@link java.util.HashSet} or {@link java.util.TreeSet} in runtime, depending on how
   *        this instance (the instance on which inspectRuntimeShape() is called) is configured.
   *     d. ByteBuffer or similar objects, where byte order matters
   *     e. boolean flags, affecting branch taking
   *     f. Arrays of objects, meeting any of conditions a-e.
   */
  void inspectRuntimeShape(RuntimeShapeInspector inspector);
}