org.apache.hadoop.hive.ql.plan.mapper.PlanMapper Maven / Gradle / Ivy

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 * 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.hadoop.hive.ql.plan.mapper;

import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.IdentityHashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Objects;
import java.util.Set;

import org.apache.hadoop.hive.ql.exec.Operator;
import org.apache.hadoop.hive.ql.optimizer.signature.OpTreeSignature;
import org.apache.hadoop.hive.ql.optimizer.signature.OpTreeSignatureFactory;
import com.facebook.presto.hive.$internal.com.google.common.annotations.VisibleForTesting;
import com.facebook.presto.hive.$internal.com.google.common.collect.Sets;

/**
 * Enables to connect related objects to eachother.
 *
 * Most importantly it aids to connect Operators to OperatorStats and probably RelNodes.
 */
public class PlanMapper {

  Set groups = new HashSet<>();
  private Map objectMap = new CompositeMap<>(OpTreeSignature.class);

  /**
   * Specialized class which can compare by identity or value; based on the key type.
   */
  private static class CompositeMap implements Map {

    Map comparedMap = new HashMap<>();
    Map identityMap = new IdentityHashMap<>();
    final Set> typeCompared;

    CompositeMap(Class... comparedTypes) {
      for (Class class1 : comparedTypes) {
        if (!Modifier.isFinal(class1.getModifiers())) {
          throw new RuntimeException(class1 + " is not final...for this to reliably work; it should be");
        }
      }
      typeCompared = Sets.newHashSet(comparedTypes);
    }

    @Override
    public int size() {
      return comparedMap.size() + identityMap.size();
    }

    @Override
    public boolean isEmpty() {
      return comparedMap.isEmpty() && identityMap.isEmpty();
    }

    @Override
    public boolean containsKey(Object key) {
      return comparedMap.containsKey(key) || identityMap.containsKey(key);
    }

    @Override
    public boolean containsValue(Object value) {
      return comparedMap.containsValue(value) || identityMap.containsValue(value);
    }

    @Override
    public V get(Object key) {
      V v0 = comparedMap.get(key);
      if (v0 != null) {
        return v0;
      }
      return identityMap.get(key);
    }

    @Override
    public V put(K key, V value) {
      if (shouldCompare(key.getClass())) {
        return comparedMap.put(key, value);
      } else {
        return identityMap.put(key, value);
      }
    }

    @Override
    public V remove(Object key) {
      if (shouldCompare(key.getClass())) {
        return comparedMap.remove(key);
      } else {
        return identityMap.remove(key);
      }
    }

    private boolean shouldCompare(Class key) {
      return typeCompared.contains(key);
    }

    @Override
    public void putAll(Map m) {
      for (Entry e : m.entrySet()) {
        put(e.getKey(), e.getValue());
      }
    }

    @Override
    public void clear() {
      comparedMap.clear();
      identityMap.clear();
    }

    @Override
    public Set keySet() {
      return Sets.union(comparedMap.keySet(), identityMap.keySet());
    }

    @Override
    public Collection values() {
      throw new UnsupportedOperationException("This method is not supported");
    }

    @Override
    public Set> entrySet() {
      return Sets.union(comparedMap.entrySet(), identityMap.entrySet());
    }

  }

  /**
   * A set of objects which are representing the same thing.
   *
   * A Group may contain different kind of things which are connected by their purpose;
   * For example currently a group may contain the following objects:
   * 
   *    Operator(s) - which are doing the actual work;
   *   there might be more than one, since an optimization may replace an operator with a new one
   *   
 Signature - to enable inter-plan look up of the same data
   *   
 OperatorStats - collected runtime information
   * 
   */
  public class EquivGroup {
    Set