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/*
 * Copyright (C) 2009 The Guava Authors
 *
 * 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.jdbc.internal.guava.collect;

import static com.facebook.presto.jdbc.internal.guava.base.Preconditions.checkNotNull;

import com.facebook.presto.jdbc.internal.guava.annotations.Beta;
import com.facebook.presto.jdbc.internal.guava.annotations.GwtCompatible;
import com.facebook.presto.jdbc.internal.guava.annotations.GwtIncompatible;
import com.facebook.presto.jdbc.internal.guava.base.MoreObjects;
import com.facebook.presto.jdbc.internal.guava.base.Preconditions;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.facebook.presto.jdbc.internal.j2objc.annotations.RetainedWith;
import com.facebook.presto.jdbc.internal.j2objc.annotations.Weak;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link SetMultimap} whose contents will never change, with many other important properties
 * detailed at {@link ImmutableCollection}.
 *
 * 

See the Guava User Guide article on immutable collections. * * @author Mike Ward * @since 2.0 */ @GwtCompatible(serializable = true, emulated = true) public class ImmutableSetMultimap extends ImmutableMultimap implements SetMultimap { /** * Returns a {@link Collector} that accumulates elements into an {@code ImmutableSetMultimap} * whose keys and values are the result of applying the provided mapping functions to the input * elements. * *

For streams with {@linkplain java.util.stream#Ordering defined encounter order}, that order * is preserved, but entries are grouped by key. * *

Example: * *

{@code
   * static final Multimap FIRST_LETTER_MULTIMAP =
   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")
   *         .collect(toImmutableSetMultimap(str -> str.charAt(0), str -> str.substring(1)));
   *
   * // is equivalent to
   *
   * static final Multimap FIRST_LETTER_MULTIMAP =
   *     new ImmutableSetMultimap.Builder()
   *         .put('b', "anana")
   *         .putAll('a', "pple", "sparagus")
   *         .putAll('c', "arrot", "herry")
   *         .build();
   * }
* * @since 21.0 */ @Beta public static Collector> toImmutableSetMultimap( Function keyFunction, Function valueFunction) { checkNotNull(keyFunction, "keyFunction"); checkNotNull(valueFunction, "valueFunction"); return Collector.of( ImmutableSetMultimap::builder, (builder, t) -> builder.put(keyFunction.apply(t), valueFunction.apply(t)), ImmutableSetMultimap.Builder::combine, ImmutableSetMultimap.Builder::build); } /** * Returns a {@code Collector} accumulating entries into an {@code ImmutableSetMultimap}. Each * input element is mapped to a key and a stream of values, each of which are put into the * resulting {@code Multimap}, in the encounter order of the stream and the encounter order of the * streams of values. * *

Example: * *

{@code
   * static final ImmutableSetMultimap FIRST_LETTER_MULTIMAP =
   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")
   *         .collect(
   *             flatteningToImmutableSetMultimap(
   *                  str -> str.charAt(0),
   *                  str -> str.substring(1).chars().mapToObj(c -> (char) c));
   *
   * // is equivalent to
   *
   * static final ImmutableSetMultimap FIRST_LETTER_MULTIMAP =
   *     ImmutableSetMultimap.builder()
   *         .putAll('b', Arrays.asList('a', 'n', 'a', 'n', 'a'))
   *         .putAll('a', Arrays.asList('p', 'p', 'l', 'e'))
   *         .putAll('c', Arrays.asList('a', 'r', 'r', 'o', 't'))
   *         .putAll('a', Arrays.asList('s', 'p', 'a', 'r', 'a', 'g', 'u', 's'))
   *         .putAll('c', Arrays.asList('h', 'e', 'r', 'r', 'y'))
   *         .build();
   *
   * // after deduplication, the resulting multimap is equivalent to
   *
   * static final ImmutableSetMultimap FIRST_LETTER_MULTIMAP =
   *     ImmutableSetMultimap.builder()
   *         .putAll('b', Arrays.asList('a', 'n'))
   *         .putAll('a', Arrays.asList('p', 'l', 'e', 's', 'a', 'r', 'g', 'u'))
   *         .putAll('c', Arrays.asList('a', 'r', 'o', 't', 'h', 'e', 'y'))
   *         .build();
   * }
   * }
* * @since 21.0 */ @Beta public static Collector> flatteningToImmutableSetMultimap( Function keyFunction, Function> valuesFunction) { checkNotNull(keyFunction); checkNotNull(valuesFunction); return Collectors.collectingAndThen( Multimaps.flatteningToMultimap( input -> checkNotNull(keyFunction.apply(input)), input -> valuesFunction.apply(input).peek(Preconditions::checkNotNull), MultimapBuilder.linkedHashKeys().linkedHashSetValues()::build), ImmutableSetMultimap::copyOf); } /** Returns the empty multimap. */ // Casting is safe because the multimap will never hold any elements. @SuppressWarnings("unchecked") public static ImmutableSetMultimap of() { return (ImmutableSetMultimap) EmptyImmutableSetMultimap.INSTANCE; } /** Returns an immutable multimap containing a single entry. */ public static ImmutableSetMultimap of(K k1, V v1) { ImmutableSetMultimap.Builder builder = ImmutableSetMultimap.builder(); builder.put(k1, v1); return builder.build(); } /** * Returns an immutable multimap containing the given entries, in order. Repeated occurrences of * an entry (according to {@link Object#equals}) after the first are ignored. */ public static ImmutableSetMultimap of(K k1, V v1, K k2, V v2) { ImmutableSetMultimap.Builder builder = ImmutableSetMultimap.builder(); builder.put(k1, v1); builder.put(k2, v2); return builder.build(); } /** * Returns an immutable multimap containing the given entries, in order. Repeated occurrences of * an entry (according to {@link Object#equals}) after the first are ignored. */ public static ImmutableSetMultimap of(K k1, V v1, K k2, V v2, K k3, V v3) { ImmutableSetMultimap.Builder builder = ImmutableSetMultimap.builder(); builder.put(k1, v1); builder.put(k2, v2); builder.put(k3, v3); return builder.build(); } /** * Returns an immutable multimap containing the given entries, in order. Repeated occurrences of * an entry (according to {@link Object#equals}) after the first are ignored. */ public static ImmutableSetMultimap of( K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4) { ImmutableSetMultimap.Builder builder = ImmutableSetMultimap.builder(); builder.put(k1, v1); builder.put(k2, v2); builder.put(k3, v3); builder.put(k4, v4); return builder.build(); } /** * Returns an immutable multimap containing the given entries, in order. Repeated occurrences of * an entry (according to {@link Object#equals}) after the first are ignored. */ public static ImmutableSetMultimap of( K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4, K k5, V v5) { ImmutableSetMultimap.Builder builder = ImmutableSetMultimap.builder(); builder.put(k1, v1); builder.put(k2, v2); builder.put(k3, v3); builder.put(k4, v4); builder.put(k5, v5); return builder.build(); } // looking for of() with > 5 entries? Use the builder instead. /** Returns a new {@link Builder}. */ public static Builder builder() { return new Builder<>(); } /** * A builder for creating immutable {@code SetMultimap} instances, especially {@code public static * final} multimaps ("constant multimaps"). Example: * *
{@code
   * static final Multimap STRING_TO_INTEGER_MULTIMAP =
   *     new ImmutableSetMultimap.Builder()
   *         .put("one", 1)
   *         .putAll("several", 1, 2, 3)
   *         .putAll("many", 1, 2, 3, 4, 5)
   *         .build();
   * }
* *

Builder instances can be reused; it is safe to call {@link #build} multiple times to build * multiple multimaps in series. Each multimap contains the key-value mappings in the previously * created multimaps. * * @since 2.0 */ public static final class Builder extends ImmutableMultimap.Builder { /** * Creates a new builder. The returned builder is equivalent to the builder generated by {@link * ImmutableSetMultimap#builder}. */ public Builder() { super(); } @Override Collection newMutableValueCollection() { return Platform.preservesInsertionOrderOnAddsSet(); } /** Adds a key-value mapping to the built multimap if it is not already present. */ @CanIgnoreReturnValue @Override public Builder put(K key, V value) { super.put(key, value); return this; } /** * Adds an entry to the built multimap if it is not already present. * * @since 11.0 */ @CanIgnoreReturnValue @Override public Builder put(Entry entry) { super.put(entry); return this; } /** * {@inheritDoc} * * @since 19.0 */ @CanIgnoreReturnValue @Beta @Override public Builder putAll(Iterable> entries) { super.putAll(entries); return this; } @CanIgnoreReturnValue @Override public Builder putAll(K key, Iterable values) { super.putAll(key, values); return this; } @CanIgnoreReturnValue @Override public Builder putAll(K key, V... values) { return putAll(key, Arrays.asList(values)); } @CanIgnoreReturnValue @Override public Builder putAll(Multimap multimap) { for (Entry> entry : multimap.asMap().entrySet()) { putAll(entry.getKey(), entry.getValue()); } return this; } @CanIgnoreReturnValue @Override Builder combine(ImmutableMultimap.Builder other) { super.combine(other); return this; } /** * {@inheritDoc} * * @since 8.0 */ @CanIgnoreReturnValue @Override public Builder orderKeysBy(Comparator keyComparator) { super.orderKeysBy(keyComparator); return this; } /** * Specifies the ordering of the generated multimap's values for each key. * *

If this method is called, the sets returned by the {@code get()} method of the generated * multimap and its {@link Multimap#asMap()} view are {@link ImmutableSortedSet} instances. * However, serialization does not preserve that property, though it does maintain the key and * value ordering. * * @since 8.0 */ // TODO: Make serialization behavior consistent. @CanIgnoreReturnValue @Override public Builder orderValuesBy(Comparator valueComparator) { super.orderValuesBy(valueComparator); return this; } /** Returns a newly-created immutable set multimap. */ @Override public ImmutableSetMultimap build() { Collection>> mapEntries = builderMap.entrySet(); if (keyComparator != null) { mapEntries = Ordering.from(keyComparator).onKeys().immutableSortedCopy(mapEntries); } return fromMapEntries(mapEntries, valueComparator); } } /** * Returns an immutable set multimap containing the same mappings as {@code multimap}. The * generated multimap's key and value orderings correspond to the iteration ordering of the {@code * multimap.asMap()} view. Repeated occurrences of an entry in the multimap after the first are * ignored. * *

Despite the method name, this method attempts to avoid actually copying the data when it is * safe to do so. The exact circumstances under which a copy will or will not be performed are * undocumented and subject to change. * * @throws NullPointerException if any key or value in {@code multimap} is null */ public static ImmutableSetMultimap copyOf( Multimap multimap) { return copyOf(multimap, null); } private static ImmutableSetMultimap copyOf( Multimap multimap, Comparator valueComparator) { checkNotNull(multimap); // eager for GWT if (multimap.isEmpty() && valueComparator == null) { return of(); } if (multimap instanceof ImmutableSetMultimap) { @SuppressWarnings("unchecked") // safe since multimap is not writable ImmutableSetMultimap kvMultimap = (ImmutableSetMultimap) multimap; if (!kvMultimap.isPartialView()) { return kvMultimap; } } return fromMapEntries(multimap.asMap().entrySet(), valueComparator); } /** * Returns an immutable multimap containing the specified entries. The returned multimap iterates * over keys in the order they were first encountered in the input, and the values for each key * are iterated in the order they were encountered. If two values for the same key are {@linkplain * Object#equals equal}, the first value encountered is used. * * @throws NullPointerException if any key, value, or entry is null * @since 19.0 */ @Beta public static ImmutableSetMultimap copyOf( Iterable> entries) { return new Builder().putAll(entries).build(); } /** Creates an ImmutableSetMultimap from an asMap.entrySet. */ static ImmutableSetMultimap fromMapEntries( Collection>> mapEntries, @Nullable Comparator valueComparator) { if (mapEntries.isEmpty()) { return of(); } ImmutableMap.Builder> builder = new ImmutableMap.Builder<>(mapEntries.size()); int size = 0; for (Entry> entry : mapEntries) { K key = entry.getKey(); Collection values = entry.getValue(); ImmutableSet set = valueSet(valueComparator, values); if (!set.isEmpty()) { builder.put(key, set); size += set.size(); } } return new ImmutableSetMultimap<>(builder.build(), size, valueComparator); } /** * Returned by get() when a missing key is provided. Also holds the comparator, if any, used for * values. */ private final transient ImmutableSet emptySet; ImmutableSetMultimap( ImmutableMap> map, int size, @Nullable Comparator valueComparator) { super(map, size); this.emptySet = emptySet(valueComparator); } // views /** * Returns an immutable set of the values for the given key. If no mappings in the multimap have * the provided key, an empty immutable set is returned. The values are in the same order as the * parameters used to build this multimap. */ @Override public ImmutableSet get(@Nullable K key) { // This cast is safe as its type is known in constructor. ImmutableSet set = (ImmutableSet) map.get(key); return MoreObjects.firstNonNull(set, emptySet); } @LazyInit @MonotonicNonNull @RetainedWith private transient ImmutableSetMultimap inverse; /** * {@inheritDoc} * *

Because an inverse of a set multimap cannot contain multiple pairs with the same key and * value, this method returns an {@code ImmutableSetMultimap} rather than the {@code * ImmutableMultimap} specified in the {@code ImmutableMultimap} class. * * @since 11.0 */ public ImmutableSetMultimap inverse() { ImmutableSetMultimap result = inverse; return (result == null) ? (inverse = invert()) : result; } private ImmutableSetMultimap invert() { Builder builder = builder(); for (Entry entry : entries()) { builder.put(entry.getValue(), entry.getKey()); } ImmutableSetMultimap invertedMultimap = builder.build(); invertedMultimap.inverse = this; return invertedMultimap; } /** * Guaranteed to throw an exception and leave the multimap unmodified. * * @throws UnsupportedOperationException always * @deprecated Unsupported operation. */ @CanIgnoreReturnValue @Deprecated @Override public ImmutableSet removeAll(Object key) { throw new UnsupportedOperationException(); } /** * Guaranteed to throw an exception and leave the multimap unmodified. * * @throws UnsupportedOperationException always * @deprecated Unsupported operation. */ @CanIgnoreReturnValue @Deprecated @Override public ImmutableSet replaceValues(K key, Iterable values) { throw new UnsupportedOperationException(); } private transient @MonotonicNonNull ImmutableSet> entries; /** * Returns an immutable collection of all key-value pairs in the multimap. Its iterator traverses * the values for the first key, the values for the second key, and so on. */ @Override public ImmutableSet> entries() { ImmutableSet> result = entries; return result == null ? (entries = new EntrySet<>(this)) : result; } private static final class EntrySet extends ImmutableSet> { @Weak private final transient ImmutableSetMultimap multimap; EntrySet(ImmutableSetMultimap multimap) { this.multimap = multimap; } @Override public boolean contains(@Nullable Object object) { if (object instanceof Entry) { Entry entry = (Entry) object; return multimap.containsEntry(entry.getKey(), entry.getValue()); } return false; } @Override public int size() { return multimap.size(); } @Override public UnmodifiableIterator> iterator() { return multimap.entryIterator(); } @Override boolean isPartialView() { return false; } } private static ImmutableSet valueSet( @Nullable Comparator valueComparator, Collection values) { return (valueComparator == null) ? ImmutableSet.copyOf(values) : ImmutableSortedSet.copyOf(valueComparator, values); } private static ImmutableSet emptySet(@Nullable Comparator valueComparator) { return (valueComparator == null) ? ImmutableSet.of() : ImmutableSortedSet.emptySet(valueComparator); } private static ImmutableSet.Builder valuesBuilder( @Nullable Comparator valueComparator) { return (valueComparator == null) ? new ImmutableSet.Builder() : new ImmutableSortedSet.Builder(valueComparator); } /** * @serialData number of distinct keys, and then for each distinct key: the key, the number of * values for that key, and the key's values */ @GwtIncompatible // java.io.ObjectOutputStream private void writeObject(ObjectOutputStream stream) throws IOException { stream.defaultWriteObject(); stream.writeObject(valueComparator()); Serialization.writeMultimap(this, stream); } @Nullable Comparator valueComparator() { return emptySet instanceof ImmutableSortedSet ? ((ImmutableSortedSet) emptySet).comparator() : null; } @GwtIncompatible // java serialization private static final class SetFieldSettersHolder { static final Serialization.FieldSetter EMPTY_SET_FIELD_SETTER = Serialization.getFieldSetter(ImmutableSetMultimap.class, "emptySet"); } @GwtIncompatible // java.io.ObjectInputStream // Serialization type safety is at the caller's mercy. @SuppressWarnings("unchecked") private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException { stream.defaultReadObject(); Comparator valueComparator = (Comparator) stream.readObject(); int keyCount = stream.readInt(); if (keyCount < 0) { throw new InvalidObjectException("Invalid key count " + keyCount); } ImmutableMap.Builder> builder = ImmutableMap.builder(); int tmpSize = 0; for (int i = 0; i < keyCount; i++) { Object key = stream.readObject(); int valueCount = stream.readInt(); if (valueCount <= 0) { throw new InvalidObjectException("Invalid value count " + valueCount); } ImmutableSet.Builder valuesBuilder = valuesBuilder(valueComparator); for (int j = 0; j < valueCount; j++) { valuesBuilder.add(stream.readObject()); } ImmutableSet valueSet = valuesBuilder.build(); if (valueSet.size() != valueCount) { throw new InvalidObjectException("Duplicate key-value pairs exist for key " + key); } builder.put(key, valueSet); tmpSize += valueCount; } ImmutableMap> tmpMap; try { tmpMap = builder.build(); } catch (IllegalArgumentException e) { throw (InvalidObjectException) new InvalidObjectException(e.getMessage()).initCause(e); } FieldSettersHolder.MAP_FIELD_SETTER.set(this, tmpMap); FieldSettersHolder.SIZE_FIELD_SETTER.set(this, tmpSize); SetFieldSettersHolder.EMPTY_SET_FIELD_SETTER.set(this, emptySet(valueComparator)); } @GwtIncompatible // not needed in emulated source. private static final long serialVersionUID = 0; }