/* * Licensed 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 com.facebook.presto.spi; import com.fasterxml.jackson.annotation.JsonSubTypes; import com.fasterxml.jackson.annotation.JsonTypeInfo; import java.util.HashSet; import java.util.Optional; import java.util.Set; import java.util.function.Function; @JsonTypeInfo( use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "@type") @JsonSubTypes({ @JsonSubTypes.Type(value = ConstantProperty.class, name = "constant"), @JsonSubTypes.Type(value = SortingProperty.class, name = "sorting"), @JsonSubTypes.Type(value = GroupingProperty.class, name = "grouping"), }) public interface LocalProperty<E> { <T> Optional<LocalProperty<T>> translate(Function<E, Optional<T>> translator); /** * Return true if the actual LocalProperty can be used to simplify this LocalProperty */ boolean isSimplifiedBy(LocalProperty<E> actual); /** * Simplfies this LocalProperty provided that the specified inputs are constants */ default Optional<LocalProperty<E>> withConstants(Set<E> constants) { Set<E> set = new HashSet<>(getColumns()); set.removeAll(constants); if (set.isEmpty()) { return Optional.empty(); } return Optional.of(constrain(set)); } /** * Return a new instance with the give (reduced) set of columns */ default LocalProperty<E> constrain(Set<E> columns) { if (!columns.equals(getColumns())) { throw new IllegalArgumentException(String.format("Cannot constrain %s with %s", this, columns)); } return this; } Set<E> getColumns(); }