robertwb commented on a change in pull request #11610: URL: https://github.com/apache/beam/pull/11610#discussion_r420415887
########## File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java ########## @@ -0,0 +1,261 @@ +/* + * 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.beam.sdk.transforms; + +import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull; + +import org.apache.beam.sdk.transforms.join.CoGbkResult; +import org.apache.beam.sdk.transforms.join.CoGroupByKey; +import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple; +import org.apache.beam.sdk.values.KV; +import org.apache.beam.sdk.values.PCollection; +import org.apache.beam.sdk.values.TupleTag; +import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables; + +public class SetFns { + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided + * {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * both pipeline is constructed and provided {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersect(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m - + * n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersectAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * pipeline is constructed {@link PCollection<T>} but not present in provided {@link + * PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.except(right)); + * }</pre> + */ + public static <T> SetImpl<T> except(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L; + return new SetImpl<>(rightCollection, exceptFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll) + * with provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m + * elements of left for all elements which are present in left but not in right. - it will output + * MAX(m - n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.exceptAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> { + if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) { + return numberOfElementsinLeft; + } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) { + return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L); + } + return 0L; + }; + return new SetImpl<>(rightCollection, exceptFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the union with provided {@code + * PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * pipeline is constructed {@link PCollection<T>} and {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.union(right)); + * }</pre> Review comment: For all of these, it'd be useful to document what the expected output is. ########## File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java ########## @@ -0,0 +1,261 @@ +/* + * 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.beam.sdk.transforms; + +import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull; + +import org.apache.beam.sdk.transforms.join.CoGbkResult; +import org.apache.beam.sdk.transforms.join.CoGroupByKey; +import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple; +import org.apache.beam.sdk.values.KV; +import org.apache.beam.sdk.values.PCollection; +import org.apache.beam.sdk.values.TupleTag; +import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables; + +public class SetFns { + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided + * {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * both pipeline is constructed and provided {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersect(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m - + * n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersectAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * pipeline is constructed {@link PCollection<T>} but not present in provided {@link + * PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.except(right)); + * }</pre> + */ + public static <T> SetImpl<T> except(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L; + return new SetImpl<>(rightCollection, exceptFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll) + * with provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m + * elements of left for all elements which are present in left but not in right. - it will output + * MAX(m - n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.exceptAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> { + if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) { + return numberOfElementsinLeft; + } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) { + return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L); + } + return 0L; + }; + return new SetImpl<>(rightCollection, exceptFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the union with provided {@code + * PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * pipeline is constructed {@link PCollection<T>} and {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.union(right)); + * }</pre> + */ + public static <T> SetImpl<T> union(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> unionFn = (numberOfElementsinLeft, numberOfElementsinRight) -> 1L; + return new SetImpl<>(rightCollection, unionFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the unionAll with provided Review comment: Isn't this just `Flatten.pcollections`? (Also, isn't that more efficient?) ########## File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java ########## @@ -0,0 +1,261 @@ +/* + * 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.beam.sdk.transforms; + +import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull; + +import org.apache.beam.sdk.transforms.join.CoGbkResult; +import org.apache.beam.sdk.transforms.join.CoGroupByKey; +import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple; +import org.apache.beam.sdk.values.KV; +import org.apache.beam.sdk.values.PCollection; +import org.apache.beam.sdk.values.TupleTag; +import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables; + +public class SetFns { + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided + * {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * both pipeline is constructed and provided {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersect(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m - + * n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersectAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * pipeline is constructed {@link PCollection<T>} but not present in provided {@link + * PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.except(right)); + * }</pre> + */ + public static <T> SetImpl<T> except(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L; + return new SetImpl<>(rightCollection, exceptFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll) + * with provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m + * elements of left for all elements which are present in left but not in right. - it will output + * MAX(m - n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.exceptAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> { + if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) { + return numberOfElementsinLeft; + } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) { + return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L); Review comment: Isn't this expression always sufficient? ########## File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java ########## @@ -0,0 +1,261 @@ +/* + * 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.beam.sdk.transforms; + +import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull; + +import org.apache.beam.sdk.transforms.join.CoGbkResult; +import org.apache.beam.sdk.transforms.join.CoGroupByKey; +import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple; +import org.apache.beam.sdk.values.KV; +import org.apache.beam.sdk.values.PCollection; +import org.apache.beam.sdk.values.TupleTag; +import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables; + +public class SetFns { Review comment: Though not as chain-able, a `PTransform<PCollectionList<T>, PCollection<T>>` feels more natural for many of these operations. ########## File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java ########## @@ -0,0 +1,261 @@ +/* + * 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.beam.sdk.transforms; + +import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull; + +import org.apache.beam.sdk.transforms.join.CoGbkResult; +import org.apache.beam.sdk.transforms.join.CoGroupByKey; +import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple; +import org.apache.beam.sdk.values.KV; +import org.apache.beam.sdk.values.PCollection; +import org.apache.beam.sdk.values.TupleTag; +import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables; + +public class SetFns { + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided + * {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * both pipeline is constructed and provided {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersect(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m - + * n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersectAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L; Review comment: Is not `Math.min(numberOfElementsinLeft, numberOfElementsinRight)` sufficient? ########## File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java ########## @@ -0,0 +1,261 @@ +/* + * 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.beam.sdk.transforms; + +import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull; + +import org.apache.beam.sdk.transforms.join.CoGbkResult; +import org.apache.beam.sdk.transforms.join.CoGroupByKey; +import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple; +import org.apache.beam.sdk.values.KV; +import org.apache.beam.sdk.values.PCollection; +import org.apache.beam.sdk.values.TupleTag; +import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables; + +public class SetFns { + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided + * {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * both pipeline is constructed and provided {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersect(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m - + * n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.intersectAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> intersectFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L; + return new SetImpl<>(rightCollection, intersectFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with + * provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * pipeline is constructed {@link PCollection<T>} but not present in provided {@link + * PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.except(right)); + * }</pre> + */ + public static <T> SetImpl<T> except(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L; + return new SetImpl<>(rightCollection, exceptFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll) + * with provided {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m + * elements of left for all elements which are present in left but not in right. - it will output + * MAX(m - n, 0) elements of left for all elements which are present in both left and right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.exceptAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> exceptFn = + (numberOfElementsinLeft, numberOfElementsinRight) -> { + if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) { + return numberOfElementsinLeft; + } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) { + return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L); + } + return 0L; + }; + return new SetImpl<>(rightCollection, exceptFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the union with provided {@code + * PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in + * pipeline is constructed {@link PCollection<T>} and {@link PCollection<T>}. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.union(right)); + * }</pre> + */ + public static <T> SetImpl<T> union(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> unionFn = (numberOfElementsinLeft, numberOfElementsinRight) -> 1L; + return new SetImpl<>(rightCollection, unionFn); + } + + /** + * Returns a new {@code SetFns.SetImpl<T>} transform that compute the unionAll with provided + * {@code PCollection<T>}. + * + * <p>The argument should not be modified after this is called. + * + * <p>The elements of the output {@link PCollection<T>} which will follow UNION_ALL semantics as + * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>} + * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m + * elements of left and m elements of right. + * + * <pre>{@code + * Pipeline p = ...; + * + * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5")); + * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6")); + * + * PCollection<String> results = + * left.apply(SetFns.unionAll(right)); + * }</pre> + */ + public static <T> SetImpl<T> unionAll(PCollection<T> rightCollection) { + checkNotNull(rightCollection, "rightCollection argument is null"); + SerializableBiFunction<Long, Long, Long> unionFn = Long::sum; + return new SetImpl<>(rightCollection, unionFn); + } + + private static <T> PCollection<T> performSetOperation( + PCollection<T> leftCollection, + PCollection<T> rightCollection, + SerializableBiFunction<Long, Long, Long> fn) { + + TupleTag<Void> leftCollectionTag = new TupleTag<>(); + TupleTag<Void> rightCollectionTag = new TupleTag<>(); + + MapElements<T, KV<T, Void>> elementToVoid = + MapElements.via( + new SimpleFunction<T, KV<T, Void>>() { + @Override + public KV<T, Void> apply(T element) { + return KV.of(element, null); + } + }); + + PCollection<KV<T, Void>> left = leftCollection.apply("PrepareLeftKV", elementToVoid); + PCollection<KV<T, Void>> right = rightCollection.apply("PrepareRightKV", elementToVoid); + + PCollection<KV<T, CoGbkResult>> coGbkResults = + KeyedPCollectionTuple.of(leftCollectionTag, left) + .and(rightCollectionTag, right) + .apply(CoGroupByKey.create()); + + return coGbkResults.apply( + ParDo.of( + new DoFn<KV<T, CoGbkResult>, T>() { + + @ProcessElement + public void processElement(ProcessContext c) { + KV<T, CoGbkResult> elementGroups = c.element(); + + CoGbkResult value = elementGroups.getValue(); Review comment: I wonder if it's worth dropping at TODO here to lift combiners through the CoGBK. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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