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/*
 * Copyright (C) 2011 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.google.common.collect;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import com.google.common.annotations.Beta;
import com.google.common.annotations.GwtIncompatible;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;

/**
 *  An immutable {@code SortedMultiset} that stores its elements in a sorted array. Some instances
 *  are ordered by an explicit comparator, while others follow the natural sort ordering of their
 *  elements. Either way, null elements are not supported.
 *
 *  

Unlike {@link Multisets#unmodifiableSortedMultiset}, which is a view of a separate * collection that can still change, an instance of {@code ImmutableSortedMultiset} contains its * own private data and will never change. This class is convenient for {@code public static * final} multisets ("constant multisets") and also lets you easily make a "defensive copy" of a * set provided to your class by a caller. * *

The multisets returned by the {@link #headMultiset}, {@link #tailMultiset}, and * {@link #subMultiset} methods share the same array as the original multiset, preventing that * array from being garbage collected. If this is a concern, the data may be copied into a * correctly-sized array by calling {@link #copyOfSorted}. * *

Note on element equivalence: The {@link #contains(Object)}, * {@link #containsAll(Collection)}, and {@link #equals(Object)} implementations must check whether * a provided object is equivalent to an element in the collection. Unlike most collections, an * {@code ImmutableSortedMultiset} doesn't use {@link Object#equals} to determine if two elements * are equivalent. Instead, with an explicit comparator, the following relation determines whether * elements {@code x} and {@code y} are equivalent: * *

   {@code
 *
 *    {(x, y) | comparator.compare(x, y) == 0}}
* *

With natural ordering of elements, the following relation determines whether two elements are * equivalent: * *

   {@code
 *
 *    {(x, y) | x.compareTo(y) == 0}}
* * Warning: Like most multisets, an {@code ImmutableSortedMultiset} will not function * correctly if an element is modified after being placed in the multiset. For this reason, and to * avoid general confusion, it is strongly recommended to place only immutable objects into this * collection. * *

Note: Although this class is not final, it cannot be subclassed as it has no public or * protected constructors. Thus, instances of this type are guaranteed to be immutable. * *

See the Guava User Guide article on * immutable collections. * * @author Louis Wasserman * @since 12.0 * * @deprecated The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023 */ @Beta @GwtIncompatible("hasn't been tested yet") @Deprecated(since = "2022-12-01") public abstract class ImmutableSortedMultiset extends ImmutableSortedMultisetFauxverideShim implements SortedMultiset { // TODO(user): GWT compatibility private static final Comparator NATURAL_ORDER = Ordering.natural(); private static final ImmutableSortedMultiset NATURAL_EMPTY_MULTISET = new EmptyImmutableSortedMultiset(NATURAL_ORDER); /** * Returns the empty immutable sorted multiset. */ @SuppressWarnings("unchecked") public static ImmutableSortedMultiset of() { return (ImmutableSortedMultiset) NATURAL_EMPTY_MULTISET; } /** * Returns an immutable sorted multiset containing a single element. */ public static > ImmutableSortedMultiset of(E element) { RegularImmutableSortedSet elementSet = (RegularImmutableSortedSet) ImmutableSortedSet.of(element); int[] counts = { 1 }; long[] cumulativeCounts = { 0, 1 }; return new RegularImmutableSortedMultiset(elementSet, counts, cumulativeCounts, 0, 1); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. * * @throws NullPointerException if any element is null */ @SuppressWarnings("unchecked") public static > ImmutableSortedMultiset of(E e1, E e2) { return copyOf(Ordering.natural(), Arrays.asList(e1, e2)); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. * * @throws NullPointerException if any element is null */ @SuppressWarnings("unchecked") public static > ImmutableSortedMultiset of(E e1, E e2, E e3) { return copyOf(Ordering.natural(), Arrays.asList(e1, e2, e3)); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. * * @throws NullPointerException if any element is null */ @SuppressWarnings("unchecked") public static > ImmutableSortedMultiset of(E e1, E e2, E e3, E e4) { return copyOf(Ordering.natural(), Arrays.asList(e1, e2, e3, e4)); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. * * @throws NullPointerException if any element is null */ @SuppressWarnings("unchecked") public static > ImmutableSortedMultiset of(E e1, E e2, E e3, E e4, E e5) { return copyOf(Ordering.natural(), Arrays.asList(e1, e2, e3, e4, e5)); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. * * @throws NullPointerException if any element is null */ @SuppressWarnings("unchecked") public static > ImmutableSortedMultiset of(E e1, E e2, E e3, E e4, E e5, E e6, E... remaining) { int size = remaining.length + 6; List all = Lists.newArrayListWithCapacity(size); Collections.addAll(all, e1, e2, e3, e4, e5, e6); Collections.addAll(all, remaining); return copyOf(Ordering.natural(), all); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. * * @throws NullPointerException if any of {@code elements} is null */ public static > ImmutableSortedMultiset copyOf(E[] elements) { return copyOf(Ordering.natural(), Arrays.asList(elements)); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. To create a copy of a {@code SortedMultiset} that preserves the * comparator, call {@link #copyOfSorted} instead. This method iterates over {@code elements} at * most once. * *

Note that if {@code s} is a {@code multiset}, then {@code * ImmutableSortedMultiset.copyOf(s)} returns an {@code ImmutableSortedMultiset} * containing each of the strings in {@code s}, while {@code ImmutableSortedMultiset.of(s)} * returns an {@code ImmutableSortedMultiset>} containing one element (the given * multiset itself). * *

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. * *

This method is not type-safe, as it may be called on elements that are not mutually * comparable. * * @throws ClassCastException if the elements are not mutually comparable * @throws NullPointerException if any of {@code elements} is null */ public static ImmutableSortedMultiset copyOf(Iterable elements) { // Hack around E not being a subtype of Comparable. // Unsafe, see ImmutableSortedMultisetFauxverideShim. @SuppressWarnings("unchecked") Ordering naturalOrder = (Ordering) Ordering.natural(); return copyOf(naturalOrder, elements); } /** * Returns an immutable sorted multiset containing the given elements sorted by their natural * ordering. * *

This method is not type-safe, as it may be called on elements that are not mutually * comparable. * * @throws ClassCastException if the elements are not mutually comparable * @throws NullPointerException if any of {@code elements} is null */ public static ImmutableSortedMultiset copyOf(Iterator elements) { // Hack around E not being a subtype of Comparable. // Unsafe, see ImmutableSortedMultisetFauxverideShim. @SuppressWarnings("unchecked") Ordering naturalOrder = (Ordering) Ordering.natural(); return copyOf(naturalOrder, elements); } /** * Returns an immutable sorted multiset containing the given elements sorted by the given {@code * Comparator}. * * @throws NullPointerException if {@code comparator} or any of {@code elements} is null */ public static ImmutableSortedMultiset copyOf(Comparator comparator, Iterator elements) { checkNotNull(comparator); return new Builder(comparator).addAll(elements).build(); } /** * Returns an immutable sorted multiset containing the given elements sorted by the given {@code * Comparator}. This method iterates over {@code elements} at most once. * *

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 {@code comparator} or any of {@code elements} is null */ public static ImmutableSortedMultiset copyOf(Comparator comparator, Iterable elements) { if (elements instanceof ImmutableSortedMultiset) { // immutable collections are always safe for covariant casts @SuppressWarnings("unchecked") ImmutableSortedMultiset multiset = (ImmutableSortedMultiset) elements; if (comparator.equals(multiset.comparator())) { if (multiset.isPartialView()) { return copyOfSortedEntries(comparator, multiset.entrySet().asList()); } else { return multiset; } } } // defensive copy elements = Lists.newArrayList(elements); TreeMultiset sortedCopy = TreeMultiset.create(checkNotNull(comparator)); Iterables.addAll(sortedCopy, elements); return copyOfSortedEntries(comparator, sortedCopy.entrySet()); } /** * Returns an immutable sorted multiset containing the elements of a sorted multiset, sorted by * the same {@code Comparator}. That behavior differs from {@link #copyOf(Iterable)}, which * always uses the natural ordering of the elements. * *

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. * *

This method is safe to use even when {@code sortedMultiset} is a synchronized or concurrent * collection that is currently being modified by another thread. * * @throws NullPointerException if {@code sortedMultiset} or any of its elements is null */ public static ImmutableSortedMultiset copyOfSorted(SortedMultiset sortedMultiset) { return copyOfSortedEntries(sortedMultiset.comparator(), Lists.newArrayList(sortedMultiset.entrySet())); } private static ImmutableSortedMultiset copyOfSortedEntries(Comparator comparator, Collection> entries) { if (entries.isEmpty()) { return emptyMultiset(comparator); } ImmutableList.Builder elementsBuilder = new ImmutableList.Builder(entries.size()); int[] counts = new int[entries.size()]; long[] cumulativeCounts = new long[entries.size() + 1]; int i = 0; for (Entry entry : entries) { elementsBuilder.add(entry.getElement()); counts[i] = entry.getCount(); cumulativeCounts[i + 1] = cumulativeCounts[i] + counts[i]; i++; } return new RegularImmutableSortedMultiset(new RegularImmutableSortedSet(elementsBuilder.build(), comparator), counts, cumulativeCounts, 0, entries.size()); } @SuppressWarnings("unchecked") static ImmutableSortedMultiset emptyMultiset(Comparator comparator) { if (NATURAL_ORDER.equals(comparator)) { return (ImmutableSortedMultiset) NATURAL_EMPTY_MULTISET; } return new EmptyImmutableSortedMultiset(comparator); } ImmutableSortedMultiset() { } @Override public final Comparator comparator() { return elementSet().comparator(); } @Override public abstract ImmutableSortedSet elementSet(); transient ImmutableSortedMultiset descendingMultiset; @Override public ImmutableSortedMultiset descendingMultiset() { ImmutableSortedMultiset result = descendingMultiset; if (result == null) { return descendingMultiset = new DescendingImmutableSortedMultiset(this); } return result; } /** * {@inheritDoc} * *

This implementation is guaranteed to throw an {@link UnsupportedOperationException}. * * @throws UnsupportedOperationException always * @deprecated Unsupported operation. */ @Deprecated @Override public final Entry pollFirstEntry() { throw new UnsupportedOperationException(); } /** * {@inheritDoc} * *

This implementation is guaranteed to throw an {@link UnsupportedOperationException}. * * @throws UnsupportedOperationException always * @deprecated Unsupported operation. */ @Deprecated @Override public final Entry pollLastEntry() { throw new UnsupportedOperationException(); } @Override public abstract ImmutableSortedMultiset headMultiset(E upperBound, BoundType boundType); @Override public ImmutableSortedMultiset subMultiset(E lowerBound, BoundType lowerBoundType, E upperBound, BoundType upperBoundType) { checkArgument(comparator().compare(lowerBound, upperBound) <= 0, "Expected lowerBound <= upperBound but %s > %s", lowerBound, upperBound); return tailMultiset(lowerBound, lowerBoundType).headMultiset(upperBound, upperBoundType); } @Override public abstract ImmutableSortedMultiset tailMultiset(E lowerBound, BoundType boundType); /** * Returns a builder that creates immutable sorted multisets with an explicit comparator. If the * comparator has a more general type than the set being generated, such as creating a {@code * SortedMultiset} with a {@code Comparator}, use the {@link Builder} * constructor instead. * * @throws NullPointerException if {@code comparator} is null */ public static Builder orderedBy(Comparator comparator) { return new Builder(comparator); } /** * Returns a builder that creates immutable sorted multisets whose elements are ordered by the * reverse of their natural ordering. * *

Note: the type parameter {@code E} extends {@code Comparable} rather than {@code * Comparable} as a workaround for javac bug 6468354. */ public static > Builder reverseOrder() { return new Builder(Ordering.natural().reverse()); } /** * Returns a builder that creates immutable sorted multisets whose elements are ordered by their * natural ordering. The sorted multisets use {@link Ordering#natural()} as the comparator. This * method provides more type-safety than {@link #builder}, as it can be called only for classes * that implement {@link Comparable}. * *

Note: the type parameter {@code E} extends {@code Comparable} rather than {@code * Comparable} as a workaround for javac bug 6468354. */ public static > Builder naturalOrder() { return new Builder(Ordering.natural()); } /** * A builder for creating immutable multiset instances, especially {@code public static final} * multisets ("constant multisets"). Example: * *

 {@code
     *
     *    public static final ImmutableSortedMultiset BEANS =
     *        new ImmutableSortedMultiset.Builder()
     *            .addCopies(Bean.COCOA, 4)
     *            .addCopies(Bean.GARDEN, 6)
     *            .addCopies(Bean.RED, 8)
     *            .addCopies(Bean.BLACK_EYED, 10)
     *            .build();}
* *

Builder instances can be reused; it is safe to call {@link #build} multiple times to build * multiple multisets in series. * * @since 12.0 * * @deprecated The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023 */ @Deprecated(since = "2022-12-01") public static class Builder extends ImmutableMultiset.Builder { private final Comparator comparator; /** * Creates a new builder. The returned builder is equivalent to the builder generated by * {@link ImmutableSortedMultiset#orderedBy(Comparator)}. */ public Builder(Comparator comparator) { super(TreeMultiset.create(comparator)); this.comparator = checkNotNull(comparator); } /** * Adds {@code element} to the {@code ImmutableSortedMultiset}. * * @param element the element to add * @return this {@code Builder} object * @throws NullPointerException if {@code element} is null */ @Override public Builder add(E element) { super.add(element); return this; } /** * Adds a number of occurrences of an element to this {@code ImmutableSortedMultiset}. * * @param element the element to add * @param occurrences the number of occurrences of the element to add. May be zero, in which * case no change will be made. * @return this {@code Builder} object * @throws NullPointerException if {@code element} is null * @throws IllegalArgumentException if {@code occurrences} is negative, or if this operation * would result in more than {@link Integer#MAX_VALUE} occurrences of the element */ @Override public Builder addCopies(E element, int occurrences) { super.addCopies(element, occurrences); return this; } /** * Adds or removes the necessary occurrences of an element such that the element attains the * desired count. * * @param element the element to add or remove occurrences of * @param count the desired count of the element in this multiset * @return this {@code Builder} object * @throws NullPointerException if {@code element} is null * @throws IllegalArgumentException if {@code count} is negative */ @Override public Builder setCount(E element, int count) { super.setCount(element, count); return this; } /** * Adds each element of {@code elements} to the {@code ImmutableSortedMultiset}. * * @param elements the elements to add * @return this {@code Builder} object * @throws NullPointerException if {@code elements} is null or contains a null element */ @Override public Builder add(E... elements) { super.add(elements); return this; } /** * Adds each element of {@code elements} to the {@code ImmutableSortedMultiset}. * * @param elements the {@code Iterable} to add to the {@code ImmutableSortedMultiset} * @return this {@code Builder} object * @throws NullPointerException if {@code elements} is null or contains a null element */ @Override public Builder addAll(Iterable elements) { super.addAll(elements); return this; } /** * Adds each element of {@code elements} to the {@code ImmutableSortedMultiset}. * * @param elements the elements to add to the {@code ImmutableSortedMultiset} * @return this {@code Builder} object * @throws NullPointerException if {@code elements} is null or contains a null element */ @Override public Builder addAll(Iterator elements) { super.addAll(elements); return this; } /** * Returns a newly-created {@code ImmutableSortedMultiset} based on the contents of the {@code * Builder}. */ @Override public ImmutableSortedMultiset build() { return copyOfSorted((SortedMultiset) contents); } } // @deprecated The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023 @Deprecated(since = "2022-12-01") private static final class SerializedForm implements Serializable { Comparator comparator; Object[] elements; int[] counts; SerializedForm(SortedMultiset multiset) { this.comparator = multiset.comparator(); int n = multiset.entrySet().size(); elements = new Object[n]; counts = new int[n]; int i = 0; for (Entry entry : multiset.entrySet()) { elements[i] = entry.getElement(); counts[i] = entry.getCount(); i++; } } @SuppressWarnings("unchecked") Object readResolve() { int n = elements.length; Builder builder = orderedBy(comparator); for (int i = 0; i < n; i++) { builder.addCopies(elements[i], counts[i]); } return builder.build(); } } @Override Object writeReplace() { return new SerializedForm(this); } }