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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 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 com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;

import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Collection;
import java.util.Comparator;
import java.util.Map.Entry;

import javax.annotation.Nullable;

/**
 * An immutable {@link ListMultimap} with reliable user-specified key and value
 * iteration order. Does not permit null keys or values.
 *
 * 

Unlike {@link Multimaps#unmodifiableListMultimap(ListMultimap)}, which is * a view of a separate multimap which can still change, an instance of * {@code ImmutableListMultimap} contains its own data and will never * change. {@code ImmutableListMultimap} is convenient for * {@code public static final} multimaps ("constant multimaps") and also lets * you easily make a "defensive copy" of a multimap provided to your class by * a caller. * *

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

See the Guava User Guide article on * immutable collections. * * @author Jared Levy * @since 2.0 (imported from Google Collections Library) */ @GwtCompatible(serializable = true, emulated = true) public class ImmutableListMultimap extends ImmutableMultimap implements ListMultimap { /** Returns the empty multimap. */ // Casting is safe because the multimap will never hold any elements. @SuppressWarnings("unchecked") public static ImmutableListMultimap of() { return (ImmutableListMultimap) EmptyImmutableListMultimap.INSTANCE; } /** * Returns an immutable multimap containing a single entry. */ public static ImmutableListMultimap of(K k1, V v1) { ImmutableListMultimap.Builder builder = ImmutableListMultimap.builder(); builder.put(k1, v1); return builder.build(); } /** * Returns an immutable multimap containing the given entries, in order. */ public static ImmutableListMultimap of(K k1, V v1, K k2, V v2) { ImmutableListMultimap.Builder builder = ImmutableListMultimap.builder(); builder.put(k1, v1); builder.put(k2, v2); return builder.build(); } /** * Returns an immutable multimap containing the given entries, in order. */ public static ImmutableListMultimap of( K k1, V v1, K k2, V v2, K k3, V v3) { ImmutableListMultimap.Builder builder = ImmutableListMultimap.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. */ public static ImmutableListMultimap of( K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4) { ImmutableListMultimap.Builder builder = ImmutableListMultimap.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. */ public static ImmutableListMultimap of( K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4, K k5, V v5) { ImmutableListMultimap.Builder builder = ImmutableListMultimap.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 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 {@code ListMultimap} instances, especially * {@code public static final} multimaps ("constant multimaps"). Example: *

   {@code
   *
   *   static final Multimap STRING_TO_INTEGER_MULTIMAP =
   *       new ImmutableListMultimap.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 (imported from Google Collections Library) */ public static final class Builder extends ImmutableMultimap.Builder { /** * Creates a new builder. The returned builder is equivalent to the builder * generated by {@link ImmutableListMultimap#builder}. */ public Builder() {} @Override public Builder put(K key, V value) { super.put(key, value); return this; } /** * {@inheritDoc} * * @since 11.0 */ @Override public Builder put( Entry entry) { super.put(entry); return this; } @Override public Builder putAll(K key, Iterable values) { super.putAll(key, values); return this; } @Override public Builder putAll(K key, V... values) { super.putAll(key, values); return this; } @Override public Builder putAll( Multimap multimap) { super.putAll(multimap); return this; } /** * {@inheritDoc} * * @since 8.0 */ @Override public Builder orderKeysBy(Comparator keyComparator) { super.orderKeysBy(keyComparator); return this; } /** * {@inheritDoc} * * @since 8.0 */ @Override public Builder orderValuesBy(Comparator valueComparator) { super.orderValuesBy(valueComparator); return this; } /** * Returns a newly-created immutable list multimap. */ @Override public ImmutableListMultimap build() { return (ImmutableListMultimap) super.build(); } } /** * Returns an immutable 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. * *

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 ImmutableListMultimap copyOf( Multimap multimap) { if (multimap.isEmpty()) { return of(); } // TODO(user): copy ImmutableSetMultimap by using asList() on the sets if (multimap instanceof ImmutableListMultimap) { @SuppressWarnings("unchecked") // safe since multimap is not writable ImmutableListMultimap kvMultimap = (ImmutableListMultimap) multimap; if (!kvMultimap.isPartialView()) { return kvMultimap; } } ImmutableMap.Builder> builder = ImmutableMap.builder(); int size = 0; for (Entry> entry : multimap.asMap().entrySet()) { ImmutableList list = ImmutableList.copyOf(entry.getValue()); if (!list.isEmpty()) { builder.put(entry.getKey(), list); size += list.size(); } } return new ImmutableListMultimap(builder.build(), size); } ImmutableListMultimap(ImmutableMap> map, int size) { super(map, size); } // views /** * Returns an immutable list of the values for the given key. If no mappings * in the multimap have the provided key, an empty immutable list is * returned. The values are in the same order as the parameters used to build * this multimap. */ @Override public ImmutableList get(@Nullable K key) { // This cast is safe as its type is known in constructor. ImmutableList list = (ImmutableList) map.get(key); return (list == null) ? ImmutableList.of() : list; } private transient ImmutableListMultimap inverse; /** * {@inheritDoc} * *

Because an inverse of a list multimap can contain multiple pairs with * the same key and value, this method returns an {@code * ImmutableListMultimap} rather than the {@code ImmutableMultimap} specified * in the {@code ImmutableMultimap} class. * * @since 11.0 */ @Override public ImmutableListMultimap inverse() { ImmutableListMultimap result = inverse; return (result == null) ? (inverse = invert()) : result; } private ImmutableListMultimap invert() { Builder builder = builder(); for (Entry entry : entries()) { builder.put(entry.getValue(), entry.getKey()); } ImmutableListMultimap invertedMultimap = builder.build(); invertedMultimap.inverse = this; return invertedMultimap; } /** * Guaranteed to throw an exception and leave the multimap unmodified. * * @throws UnsupportedOperationException always * @deprecated Unsupported operation. */ @Deprecated @Override public ImmutableList removeAll(Object key) { throw new UnsupportedOperationException(); } /** * Guaranteed to throw an exception and leave the multimap unmodified. * * @throws UnsupportedOperationException always * @deprecated Unsupported operation. */ @Deprecated @Override public ImmutableList replaceValues( K key, Iterable values) { throw new UnsupportedOperationException(); } /** * @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(); Serialization.writeMultimap(this, stream); } @GwtIncompatible("java.io.ObjectInputStream") private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException { stream.defaultReadObject(); 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); } Object[] array = new Object[valueCount]; for (int j = 0; j < valueCount; j++) { array[j] = stream.readObject(); } builder.put(key, ImmutableList.copyOf(array)); 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); } @GwtIncompatible("Not needed in emulated source") private static final long serialVersionUID = 0; }





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