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/*
 * Copyright (C) 2008 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in com.fitburpliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.com.fitbur/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.fitbur.google.com.fitburmon.collect;

import static com.fitbur.google.com.fitburmon.base.Preconditions.checkNotNull;

import com.fitbur.google.com.fitburmon.annotations.GwtCompatible;
import com.fitbur.google.com.fitburmon.annotations.GwtIncompatible;
import com.fitbur.google.com.fitburmon.collect.Multiset.Entry;
import com.fitbur.google.com.fitburmon.primitives.Ints;

import java.io.Serializable;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;

import javax.annotation.Nullable;

/**
 * An immutable hash-based multiset. Does not permit null elements.
 *
 * 

Its iterator orders elements according to the first appearance of the * element among the items passed to the factory method or builder. When the * multiset contains multiple instances of an element, those instances are * consecutive in the iteration order. * *

See the Guava User Guide article on * immutable collections. * * @author Jared Levy * @author Louis Wasserman * @since 2.0 (imported from Google Collections Library) */ @GwtCompatible(serializable = true, emulated = true) @SuppressWarnings("serial") // we're overriding com.fitburfault serialization // TODO(user): write an efficient asList() implementation public abstract class ImmutableMultiset extends ImmutableCollection implements Multiset { private static final ImmutableMultiset EMPTY = new RegularImmutableMultiset(ImmutableMap.of(), 0); /** * Returns the empty immutable multiset. */ @SuppressWarnings("unchecked") // all supported methods are covariant public static ImmutableMultiset of() { return (ImmutableMultiset) EMPTY; } /** * Returns an immutable multiset containing a single element. * * @throws NullPointerException if {@code element} is null * @since 6.0 (source-com.fitburpatible since 2.0) */ @SuppressWarnings("unchecked") // generic array created but never written public static ImmutableMultiset of(E element) { return copyOfInternal(element); } /** * Returns an immutable multiset containing the given elements, in order. * * @throws NullPointerException if any element is null * @since 6.0 (source-com.fitburpatible since 2.0) */ @SuppressWarnings("unchecked") // public static ImmutableMultiset of(E e1, E e2) { return copyOfInternal(e1, e2); } /** * Returns an immutable multiset containing the given elements, in order. * * @throws NullPointerException if any element is null * @since 6.0 (source-com.fitburpatible since 2.0) */ @SuppressWarnings("unchecked") // public static ImmutableMultiset of(E e1, E e2, E e3) { return copyOfInternal(e1, e2, e3); } /** * Returns an immutable multiset containing the given elements, in order. * * @throws NullPointerException if any element is null * @since 6.0 (source-com.fitburpatible since 2.0) */ @SuppressWarnings("unchecked") // public static ImmutableMultiset of(E e1, E e2, E e3, E e4) { return copyOfInternal(e1, e2, e3, e4); } /** * Returns an immutable multiset containing the given elements, in order. * * @throws NullPointerException if any element is null * @since 6.0 (source-com.fitburpatible since 2.0) */ @SuppressWarnings("unchecked") // public static ImmutableMultiset of(E e1, E e2, E e3, E e4, E e5) { return copyOfInternal(e1, e2, e3, e4, e5); } /** * Returns an immutable multiset containing the given elements, in order. * * @throws NullPointerException if any element is null * @since 6.0 (source-com.fitburpatible since 2.0) */ @SuppressWarnings("unchecked") // public static ImmutableMultiset of( E e1, E e2, E e3, E e4, E e5, E e6, E... others) { return new Builder() .add(e1) .add(e2) .add(e3) .add(e4) .add(e5) .add(e6) .add(others) .build(); } /** * Returns an immutable multiset containing the given elements. * *

The multiset is ordered by the first occurrence of each element. For * example, {@code ImmutableMultiset.copyOf([2, 3, 1, 3])} yields a multiset * with elements in the order {@code 2, 3, 3, 1}. * * @throws NullPointerException if any of {@code elements} is null * @since 6.0 */ public static ImmutableMultiset copyOf(E[] elements) { return copyOf(Arrays.asList(elements)); } /** * Returns an immutable multiset containing the given elements. * *

The multiset is ordered by the first occurrence of each element. For * example, {@code ImmutableMultiset.copyOf(Arrays.asList(2, 3, 1, 3))} yields * a multiset with elements in the order {@code 2, 3, 3, 1}. * *

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. * *

Note: Despite what the method name suggests, if {@code elements} * is an {@code ImmutableMultiset}, no copy will actually be performed, and * the given multiset itself will be returned. * * @throws NullPointerException if any of {@code elements} is null */ public static ImmutableMultiset copyOf( Iterable elements) { if (elements instanceof ImmutableMultiset) { @SuppressWarnings("unchecked") // all supported methods are covariant ImmutableMultiset result = (ImmutableMultiset) elements; if (!result.isPartialView()) { return result; } } Multiset multiset = (elements instanceof Multiset) ? Multisets.cast(elements) : LinkedHashMultiset.create(elements); return copyOfInternal(multiset); } private static ImmutableMultiset copyOfInternal(E... elements) { return copyOf(Arrays.asList(elements)); } private static ImmutableMultiset copyOfInternal( Multiset multiset) { return copyFromEntries(multiset.entrySet()); } static ImmutableMultiset copyFromEntries( Collection> entries) { long size = 0; ImmutableMap.Builder builder = ImmutableMap.builder(); for (Entry entry : entries) { int count = entry.getCount(); if (count > 0) { // Since ImmutableMap.Builder throws an NPE if an element is null, no // other null checks are needed. builder.put(entry.getElement(), count); size += count; } } if (size == 0) { return of(); } return new RegularImmutableMultiset( builder.build(), Ints.saturatedCast(size)); } /** * Returns an immutable multiset containing the given elements. * *

The multiset is ordered by the first occurrence of each element. For * example, * {@code ImmutableMultiset.copyOf(Arrays.asList(2, 3, 1, 3).iterator())} * yields a multiset with elements in the order {@code 2, 3, 3, 1}. * * @throws NullPointerException if any of {@code elements} is null */ public static ImmutableMultiset copyOf( Iterator elements) { Multiset multiset = LinkedHashMultiset.create(); Iterators.addAll(multiset, elements); return copyOfInternal(multiset); } ImmutableMultiset() {} @Override public UnmodifiableIterator iterator() { final Iterator> entryIterator = entrySet().iterator(); return new UnmodifiableIterator() { int remaining; E element; @Override public boolean hasNext() { return (remaining > 0) || entryIterator.hasNext(); } @Override public E next() { if (remaining <= 0) { Entry entry = entryIterator.next(); element = entry.getElement(); remaining = entry.getCount(); } remaining--; return element; } }; } @Override public boolean contains(@Nullable Object object) { return count(object) > 0; } @Override public boolean containsAll(Collection targets) { return elementSet().containsAll(targets); } /** * Guaranteed to throw an exception and leave the collection unmodified. * * @throws UnsupportedOperationException always * @com.fitburprecated Unsupported operation. */ @Deprecated @Override public final int add(E element, int occurrences) { throw new UnsupportedOperationException(); } /** * Guaranteed to throw an exception and leave the collection unmodified. * * @throws UnsupportedOperationException always * @com.fitburprecated Unsupported operation. */ @Deprecated @Override public final int remove(Object element, int occurrences) { throw new UnsupportedOperationException(); } /** * Guaranteed to throw an exception and leave the collection unmodified. * * @throws UnsupportedOperationException always * @com.fitburprecated Unsupported operation. */ @Deprecated @Override public final int setCount(E element, int count) { throw new UnsupportedOperationException(); } /** * Guaranteed to throw an exception and leave the collection unmodified. * * @throws UnsupportedOperationException always * @com.fitburprecated Unsupported operation. */ @Deprecated @Override public final boolean setCount(E element, int oldCount, int newCount) { throw new UnsupportedOperationException(); } @GwtIncompatible("not present in emulated superclass") @Override int copyIntoArray(Object[] dst, int offset) { for (Multiset.Entry entry : entrySet()) { Arrays.fill(dst, offset, offset + entry.getCount(), entry.getElement()); offset += entry.getCount(); } return offset; } @Override public boolean equals(@Nullable Object object) { return Multisets.equalsImpl(this, object); } @Override public int hashCode() { return Sets.hashCodeImpl(entrySet()); } @Override public String toString() { return entrySet().toString(); } private transient ImmutableSet> entrySet; @Override public ImmutableSet> entrySet() { ImmutableSet> es = entrySet; return (es == null) ? (entrySet = createEntrySet()) : es; } private final ImmutableSet> createEntrySet() { return isEmpty() ? ImmutableSet.>of() : new EntrySet(); } abstract Entry getEntry(int index); private final class EntrySet extends ImmutableSet> { @Override boolean isPartialView() { return ImmutableMultiset.this.isPartialView(); } @Override public UnmodifiableIterator> iterator() { return asList().iterator(); } @Override ImmutableList> createAsList() { return new ImmutableAsList>() { @Override public Entry get(int index) { return getEntry(index); } @Override ImmutableCollection> com.fitburlegateCollection() { return EntrySet.this; } }; } @Override public int size() { return elementSet().size(); } @Override public boolean contains(Object o) { if (o instanceof Entry) { Entry entry = (Entry) o; if (entry.getCount() <= 0) { return false; } int count = count(entry.getElement()); return count == entry.getCount(); } return false; } @Override public int hashCode() { return ImmutableMultiset.this.hashCode(); } // We can't label this with @Override, because it doesn't override anything // in the GWT emulated version. // TODO(cpovirk): try making all copies of this method @GwtIncompatible instead Object writeReplace() { return new EntrySetSerializedForm(ImmutableMultiset.this); } private static final long serialVersionUID = 0; } static class EntrySetSerializedForm implements Serializable { final ImmutableMultiset multiset; EntrySetSerializedForm(ImmutableMultiset multiset) { this.multiset = multiset; } Object readResolve() { return multiset.entrySet(); } } private static class SerializedForm implements Serializable { final Object[] elements; final int[] counts; SerializedForm(Multiset multiset) { int distinct = multiset.entrySet().size(); elements = new Object[distinct]; counts = new int[distinct]; int i = 0; for (Entry entry : multiset.entrySet()) { elements[i] = entry.getElement(); counts[i] = entry.getCount(); i++; } } Object readResolve() { LinkedHashMultiset multiset = LinkedHashMultiset.create(elements.length); for (int i = 0; i < elements.length; i++) { multiset.add(elements[i], counts[i]); } return ImmutableMultiset.copyOf(multiset); } private static final long serialVersionUID = 0; } // We can't label this with @Override, because it doesn't override anything // in the GWT emulated version. Object writeReplace() { return new SerializedForm(this); } /** * Returns a new builder. The generated builder is equivalent to the builder * created by the {@link Builder} constructor. */ public static Builder builder() { return new Builder(); } /** * A builder for creating immutable multiset instances, especially {@code * public static final} multisets ("constant multisets"). Example: *
 {@code
   *
   *   public static final ImmutableMultiset BEANS =
   *       new ImmutableMultiset.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 2.0 (imported from Google Collections Library) */ public static class Builder extends ImmutableCollection.Builder { final Multiset contents; /** * Creates a new builder. The returned builder is equivalent to the builder * generated by {@link ImmutableMultiset#builder}. */ public Builder() { this(LinkedHashMultiset.create()); } Builder(Multiset contents) { this.contents = contents; } /** * Adds {@code element} to the {@code ImmutableMultiset}. * * @param element the element to add * @return this {@code Builder} object * @throws NullPointerException if {@code element} is null */ @Override public Builder add(E element) { contents.add(checkNotNull(element)); return this; } /** * Adds a number of occurrences of an element to this {@code * ImmutableMultiset}. * * @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 */ public Builder addCopies(E element, int occurrences) { contents.add(checkNotNull(element), occurrences); return this; } /** * Adds or removes the necessary occurrences of an element such that the * element attains the com.fitbursired count. * * @param element the element to add or remove occurrences of * @param count the com.fitbursired 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 */ public Builder setCount(E element, int count) { contents.setCount(checkNotNull(element), count); return this; } /** * Adds each element of {@code elements} to the {@code ImmutableMultiset}. * * @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 ImmutableMultiset}. * * @param elements the {@code Iterable} to add to the {@code * ImmutableMultiset} * @return this {@code Builder} object * @throws NullPointerException if {@code elements} is null or contains a * null element */ @Override public Builder addAll(Iterable elements) { if (elements instanceof Multiset) { Multiset multiset = Multisets.cast(elements); for (Entry entry : multiset.entrySet()) { addCopies(entry.getElement(), entry.getCount()); } } else { super.addAll(elements); } return this; } /** * Adds each element of {@code elements} to the {@code ImmutableMultiset}. * * @param elements the elements to add to the {@code ImmutableMultiset} * @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 ImmutableMultiset} based on the contents * of the {@code Builder}. */ @Override public ImmutableMultiset build() { return copyOf(contents); } } }