rubenada commented on a change in pull request #2329: URL: https://github.com/apache/calcite/pull/2329#discussion_r568456474
########## File path: linq4j/src/main/java/org/apache/calcite/linq4j/MergeUnionEnumerator.java ########## @@ -0,0 +1,198 @@ +/* + * 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.linq4j; + +import org.apache.calcite.linq4j.function.EqualityComparer; +import org.apache.calcite.linq4j.function.Function1; + +import org.checkerframework.checker.initialization.qual.UnknownInitialization; +import org.checkerframework.checker.nullness.qual.Nullable; +import org.checkerframework.checker.nullness.qual.RequiresNonNull; + +import java.util.ArrayList; +import java.util.Comparator; +import java.util.HashSet; +import java.util.List; +import java.util.NoSuchElementException; +import java.util.Set; + +/** + * Performs a union (or union all) of all its inputs (which must be already sorted), + * respecting the order. + * @param <TSource> record type + * @param <TKey> sort key + */ +final class MergeUnionEnumerator<TSource, TKey> implements Enumerator<TSource> { + private final List<Enumerator<TSource>> inputs; + private final TSource[] currentInputsValues; + private final Function1<TSource, TKey> sortKeySelector; + private final Comparator<TKey> sortComparator; + private TSource currentValue; + private int activeInputs; + + // Set to control duplicates, only used if "all" is false + private final @Nullable Set<EnumerableDefaults.Wrapped<TSource>> processed; + private final @Nullable Function1<TSource, EnumerableDefaults.Wrapped<TSource>> wrapper; + + private static final Object NOT_INIT = new Object(); + private static final Object FINISHED = new Object(); Review comment: changed: source state now tracked via boolean array `inputsFinished` ########## File path: linq4j/src/main/java/org/apache/calcite/linq4j/MergeUnionEnumerator.java ########## @@ -0,0 +1,198 @@ +/* + * 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.linq4j; + +import org.apache.calcite.linq4j.function.EqualityComparer; +import org.apache.calcite.linq4j.function.Function1; + +import org.checkerframework.checker.initialization.qual.UnknownInitialization; +import org.checkerframework.checker.nullness.qual.Nullable; +import org.checkerframework.checker.nullness.qual.RequiresNonNull; + +import java.util.ArrayList; +import java.util.Comparator; +import java.util.HashSet; +import java.util.List; +import java.util.NoSuchElementException; +import java.util.Set; + +/** + * Performs a union (or union all) of all its inputs (which must be already sorted), + * respecting the order. + * @param <TSource> record type + * @param <TKey> sort key + */ +final class MergeUnionEnumerator<TSource, TKey> implements Enumerator<TSource> { + private final List<Enumerator<TSource>> inputs; + private final TSource[] currentInputsValues; Review comment: Changed: everything as array ########## File path: linq4j/src/main/java/org/apache/calcite/linq4j/MergeUnionEnumerator.java ########## @@ -0,0 +1,198 @@ +/* + * 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.linq4j; + +import org.apache.calcite.linq4j.function.EqualityComparer; +import org.apache.calcite.linq4j.function.Function1; + +import org.checkerframework.checker.initialization.qual.UnknownInitialization; +import org.checkerframework.checker.nullness.qual.Nullable; +import org.checkerframework.checker.nullness.qual.RequiresNonNull; + +import java.util.ArrayList; +import java.util.Comparator; +import java.util.HashSet; +import java.util.List; +import java.util.NoSuchElementException; +import java.util.Set; + +/** + * Performs a union (or union all) of all its inputs (which must be already sorted), + * respecting the order. + * @param <TSource> record type + * @param <TKey> sort key + */ +final class MergeUnionEnumerator<TSource, TKey> implements Enumerator<TSource> { + private final List<Enumerator<TSource>> inputs; + private final TSource[] currentInputsValues; + private final Function1<TSource, TKey> sortKeySelector; + private final Comparator<TKey> sortComparator; + private TSource currentValue; + private int activeInputs; + + // Set to control duplicates, only used if "all" is false + private final @Nullable Set<EnumerableDefaults.Wrapped<TSource>> processed; + private final @Nullable Function1<TSource, EnumerableDefaults.Wrapped<TSource>> wrapper; + + private static final Object NOT_INIT = new Object(); + private static final Object FINISHED = new Object(); + + MergeUnionEnumerator( + List<Enumerable<TSource>> sources, + Function1<TSource, TKey> sortKeySelector, + Comparator<TKey> sortComparator, + boolean all, + EqualityComparer<TSource> equalityComparer) { + this.sortKeySelector = sortKeySelector; + this.sortComparator = sortComparator; + + if (all) { + this.processed = null; + this.wrapper = null; + } else { + this.processed = new HashSet<>(); + this.wrapper = EnumerableDefaults.wrapperFor(equalityComparer); + } + + final int size = sources.size(); + this.inputs = new ArrayList<>(size); + for (Enumerable<TSource> source : sources) { + this.inputs.add(source.enumerator()); + } + + //noinspection unchecked + this.currentInputsValues = (TSource[]) new Object[size]; + this.activeInputs = this.currentInputsValues.length; + //noinspection unchecked + this.currentValue = (TSource) NOT_INIT; + + initEnumerators(); + } + + @RequiresNonNull("inputs") + @SuppressWarnings("method.invocation.invalid") + private void initEnumerators(@UnknownInitialization MergeUnionEnumerator<TSource, TKey> this) { + for (int i = 0; i < inputs.size(); i++) { + moveEnumerator(i); + } + } + + private void moveEnumerator(int i) { + final Enumerator<TSource> enumerator = inputs.get(i); + if (!enumerator.moveNext()) { + activeInputs--; + //noinspection unchecked + currentInputsValues[i] = (TSource) FINISHED; + } else { + currentInputsValues[i] = enumerator.current(); + } + } + + private boolean checkNotDuplicated(TSource value) { + if (processed == null) { + return true; // UNION ALL: no need to check duplicates + } + + // check duplicates + @SuppressWarnings("dereference.of.nullable") + final EnumerableDefaults.Wrapped<TSource> wrapped = wrapper.apply(value); + if (!processed.contains(wrapped)) { + if (!processed.isEmpty()) { + // Since inputs are sorted, we do not need to keep in the set all the items that we + // have previously returned, just the ones with the same key, as soon as we see a new + // key, we can clear the set containing the items belonging to the previous key + final EnumerableDefaults.Wrapped<TSource> wrappedItemInSet = processed.iterator().next(); Review comment: Changed: keep `currentKeyInProcessedSet` variable ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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