content: /*
   * 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.calcite.rel.logical;
  
  import org.apache.calcite.plan.Convention;
  import org.apache.calcite.plan.RelOptCluster;
  import org.apache.calcite.plan.RelTraitSet;
  import org.apache.calcite.rel.RelInput;
  import org.apache.calcite.rel.RelNode;
  import org.apache.calcite.rel.RelShuttle;
  import org.apache.calcite.rel.core.AsofJoin;
  import org.apache.calcite.rel.core.Join;
  import org.apache.calcite.rel.core.JoinRelType;
  import org.apache.calcite.rel.hint.RelHint;
  import org.apache.calcite.rel.type.RelDataTypeField;
  import org.apache.calcite.rex.RexNode;
  
  import com.google.common.collect.ImmutableList;
  import com.google.common.collect.ImmutableSet;
  
  import org.checkerframework.checker.nullness.qual.Nullable;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Objects;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * Sub-class of {@link AsofJoin} encoding ASOF joins.
   * Adapted from the {@link LogicalJoin} implementation.
   */
  public final class LogicalAsofJoin extends AsofJoin {
    //~ Instance fields --------------------------------------------------------
  
    private final ImmutableList<RelDataTypeField> systemFieldList;
  
    //~ Constructors -----------------------------------------------------------
  
    /**
     * Creates a LogicalAsofJoin.
     *
     * <p>Use {@link #create} unless you know what you're doing.
     *
     * @param cluster          Cluster
     * @param traitSet         Trait set
     * @param hints            Hints
     * @param left             Left input
     * @param right            Right input
     * @param condition        Join condition
     * @param matchCondition   Temporal condition
     * @param systemFieldList  List of system fields that will be prefixed to
     *                         output row type; typically empty but must not be null
     */
    public LogicalAsofJoin(
        RelOptCluster cluster,
        RelTraitSet traitSet,
        List<RelHint> hints,
        RelNode left,
        RelNode right,
        RexNode condition,
        RexNode matchCondition,
        JoinRelType joinType,
        ImmutableList<RelDataTypeField> systemFieldList) {
      super(cluster, traitSet, hints, left, right,
          condition, matchCondition, ImmutableSet.of(), joinType);
      this.systemFieldList = requireNonNull(systemFieldList, "systemFieldList");
    }
  
    /**
     * Creates a LogicalAsofJoin by parsing serialized output.
     */
    public LogicalAsofJoin(RelInput input) {
      this(input.getCluster(), input.getCluster().traitSetOf(Convention.NONE),
          new ArrayList<>(),
          input.getInputs().get(0), input.getInputs().get(1),
          requireNonNull(input.getExpression("condition"), "condition"),
          requireNonNull(input.getExpression("matchCondition"), "matchCondition"),
          requireNonNull(input.getEnum("joinType", JoinRelType.class), "joinType"),
          ImmutableList.of());
    }
  
    /** Creates a LogicalAsofJoin. */
    public static LogicalAsofJoin create(RelNode left, RelNode right, List<RelHint> hints,
        RexNode condition, RexNode matchCondition,
        JoinRelType joinType,
        ImmutableList<RelDataTypeField> systemFieldList) {
      final RelOptCluster cluster = left.getCluster();
      final RelTraitSet traitSet = cluster.traitSetOf(Convention.NONE);
      return new LogicalAsofJoin(cluster, traitSet, hints, left, right, condition, matchCondition,
          joinType, systemFieldList);
    }
  
    //~ Methods ----------------------------------------------------------------
  
    public LogicalAsofJoin copy(
        RelTraitSet traitSet, RexNode conditionExpr, RexNode matchConditionExpr,
        RelNode left, RelNode right) {
      assert traitSet.containsIfApplicable(Convention.NONE);
      return new LogicalAsofJoin(getCluster(),
          getCluster().traitSetOf(Convention.NONE), hints, left, right, conditionExpr,
          matchConditionExpr, joinType, systemFieldList);
    }
  
    @Override public RelNode accept(RelShuttle shuttle) {
      return shuttle.visit(this);
    }
  
    @Override public boolean deepEquals(@Nullable Object obj) {
      if (this == obj) {
        return true;
      }
      return deepEquals0(obj)
          && matchCondition.equals(((LogicalAsofJoin) obj).matchCondition)
          && systemFieldList.equals(((LogicalAsofJoin) obj).systemFieldList);
    }
  
    @Override public int deepHashCode() {
      return Objects.hash(deepHashCode0(), systemFieldList);
    }
  
    @Override public ImmutableList<RelDataTypeField> getSystemFieldList() {
      return systemFieldList;
    }
  
    @Override public Join copy(
        RelTraitSet traitSet, RexNode conditionExpr, RelNode left, RelNode right,
        JoinRelType joinType, boolean semiJoinDone) {
      // This method does not provide the matchCondition as an argument, so it should never be called
      throw new RuntimeException("This method should not be called");
    }
  
    @Override public Join copy(RelTraitSet traitSet, List<RelNode> inputs) {
      assert inputs.size() == 2;
      return new LogicalAsofJoin(getCluster(), traitSet, hints,
          inputs.get(0), inputs.get(1),
          getCondition(), getMatchCondition(), joinType, systemFieldList);
    }
  
    @Override public RelNode withHints(List<RelHint> hintList) {
      return new LogicalAsofJoin(getCluster(), traitSet, hintList,
          left, right, condition, matchCondition, joinType, systemFieldList);
    }
  }
  