com.google.common.collect.RegularImmutableBiMap Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* 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 static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkPositionIndex;
import static com.google.common.collect.CollectPreconditions.checkEntryNotNull;
import static com.google.common.collect.ImmutableMapEntry.createEntryArray;
import static com.google.common.collect.RegularImmutableMap.MAX_HASH_BUCKET_LENGTH;
import static com.google.common.collect.RegularImmutableMap.checkNoConflictInKeyBucket;
import static java.util.Objects.requireNonNull;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableMapEntry.NonTerminalImmutableBiMapEntry;
import com.google.common.collect.RegularImmutableMap.BucketOverflowException;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.RetainedWith;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.function.BiConsumer;
import java.util.function.Consumer;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;
/**
* Bimap with zero or more mappings.
*
* @author Louis Wasserman
*/
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
@ElementTypesAreNonnullByDefault
class RegularImmutableBiMap extends ImmutableBiMap {
static final RegularImmutableBiMap EMPTY =
new RegularImmutableBiMap<>(
null, null, (Entry[]) ImmutableMap.EMPTY_ENTRY_ARRAY, 0, 0);
static final double MAX_LOAD_FACTOR = 1.2;
@CheckForNull private final transient @Nullable ImmutableMapEntry[] keyTable;
@CheckForNull private final transient @Nullable ImmutableMapEntry[] valueTable;
@VisibleForTesting final transient Entry[] entries;
private final transient int mask;
private final transient int hashCode;
static ImmutableBiMap fromEntries(Entry... entries) {
return fromEntryArray(entries.length, entries);
}
static ImmutableBiMap fromEntryArray(int n, @Nullable Entry[] entryArray) {
checkPositionIndex(n, entryArray.length);
int tableSize = Hashing.closedTableSize(n, MAX_LOAD_FACTOR);
int mask = tableSize - 1;
@Nullable ImmutableMapEntry[] keyTable = createEntryArray(tableSize);
@Nullable ImmutableMapEntry[] valueTable = createEntryArray(tableSize);
/*
* The cast is safe: n==entryArray.length means that we have filled the whole array with Entry
* instances, in which case it is safe to cast it from an array of nullable entries to an array
* of non-null entries.
*/
@SuppressWarnings("nullness")
Entry[] entries =
(n == entryArray.length) ? (Entry[]) entryArray : createEntryArray(n);
int hashCode = 0;
for (int i = 0; i < n; i++) {
// requireNonNull is safe because the first `n` elements have been filled in.
Entry entry = requireNonNull(entryArray[i]);
K key = entry.getKey();
V value = entry.getValue();
checkEntryNotNull(key, value);
int keyHash = key.hashCode();
int valueHash = value.hashCode();
int keyBucket = Hashing.smear(keyHash) & mask;
int valueBucket = Hashing.smear(valueHash) & mask;
ImmutableMapEntry nextInKeyBucket = keyTable[keyBucket];
ImmutableMapEntry nextInValueBucket = valueTable[valueBucket];
try {
checkNoConflictInKeyBucket(key, value, nextInKeyBucket, /* throwIfDuplicateKeys= */ true);
checkNoConflictInValueBucket(value, entry, nextInValueBucket);
} catch (BucketOverflowException e) {
return JdkBackedImmutableBiMap.create(n, entryArray);
}
ImmutableMapEntry newEntry =
(nextInValueBucket == null && nextInKeyBucket == null)
? RegularImmutableMap.makeImmutable(entry, key, value)
: new NonTerminalImmutableBiMapEntry<>(
key, value, nextInKeyBucket, nextInValueBucket);
keyTable[keyBucket] = newEntry;
valueTable[valueBucket] = newEntry;
entries[i] = newEntry;
hashCode += keyHash ^ valueHash;
}
return new RegularImmutableBiMap<>(keyTable, valueTable, entries, mask, hashCode);
}
private RegularImmutableBiMap(
@CheckForNull @Nullable ImmutableMapEntry[] keyTable,
@CheckForNull @Nullable ImmutableMapEntry[] valueTable,
Entry[] entries,
int mask,
int hashCode) {
this.keyTable = keyTable;
this.valueTable = valueTable;
this.entries = entries;
this.mask = mask;
this.hashCode = hashCode;
}
// checkNoConflictInKeyBucket is static imported from RegularImmutableMap
/**
* @throws IllegalArgumentException if another entry in the bucket has the same key
* @throws BucketOverflowException if this bucket has too many entries, which may indicate a hash
* flooding attack
*/
private static void checkNoConflictInValueBucket(
Object value, Entry entry, @CheckForNull ImmutableMapEntry valueBucketHead)
throws BucketOverflowException {
int bucketSize = 0;
for (; valueBucketHead != null; valueBucketHead = valueBucketHead.getNextInValueBucket()) {
checkNoConflict(!value.equals(valueBucketHead.getValue()), "value", entry, valueBucketHead);
if (++bucketSize > MAX_HASH_BUCKET_LENGTH) {
throw new BucketOverflowException();
}
}
}
@Override
@CheckForNull
public V get(@CheckForNull Object key) {
return RegularImmutableMap.get(key, keyTable, mask);
}
@Override
ImmutableSet> createEntrySet() {
return isEmpty()
? ImmutableSet.>of()
: new ImmutableMapEntrySet.RegularEntrySet(this, entries);
}
@Override
ImmutableSet createKeySet() {
return new ImmutableMapKeySet<>(this);
}
@Override
public void forEach(BiConsumer action) {
checkNotNull(action);
for (Entry entry : entries) {
action.accept(entry.getKey(), entry.getValue());
}
}
@Override
boolean isHashCodeFast() {
return true;
}
@Override
public int hashCode() {
return hashCode;
}
@Override
boolean isPartialView() {
return false;
}
@Override
public int size() {
return entries.length;
}
@LazyInit @RetainedWith @CheckForNull private transient ImmutableBiMap inverse;
@Override
public ImmutableBiMap inverse() {
if (isEmpty()) {
return ImmutableBiMap.of();
}
ImmutableBiMap result = inverse;
return (result == null) ? inverse = new Inverse() : result;
}
private final class Inverse extends ImmutableBiMap {
@Override
public int size() {
return inverse().size();
}
@Override
public ImmutableBiMap inverse() {
return RegularImmutableBiMap.this;
}
@Override
public void forEach(BiConsumer action) {
checkNotNull(action);
RegularImmutableBiMap.this.forEach((k, v) -> action.accept(v, k));
}
@Override
@CheckForNull
public K get(@CheckForNull Object value) {
if (value == null || valueTable == null) {
return null;
}
int bucket = Hashing.smear(value.hashCode()) & mask;
for (ImmutableMapEntry entry = valueTable[bucket];
entry != null;
entry = entry.getNextInValueBucket()) {
if (value.equals(entry.getValue())) {
return entry.getKey();
}
}
return null;
}
@Override
ImmutableSet createKeySet() {
return new ImmutableMapKeySet<>(this);
}
@Override
ImmutableSet> createEntrySet() {
return new InverseEntrySet();
}
final class InverseEntrySet extends ImmutableMapEntrySet {
@Override
ImmutableMap map() {
return Inverse.this;
}
@Override
boolean isHashCodeFast() {
return true;
}
@Override
public int hashCode() {
return hashCode;
}
@Override
public UnmodifiableIterator> iterator() {
return asList().iterator();
}
@Override
public void forEach(Consumer> action) {
asList().forEach(action);
}
@Override
ImmutableList> createAsList() {
return new ImmutableAsList>() {
@Override
public Entry get(int index) {
Entry entry = entries[index];
return Maps.immutableEntry(entry.getValue(), entry.getKey());
}
@Override
ImmutableCollection> delegateCollection() {
return InverseEntrySet.this;
}
};
}
}
@Override
boolean isPartialView() {
return false;
}
@Override
@J2ktIncompatible // serialization
Object writeReplace() {
return new InverseSerializedForm<>(RegularImmutableBiMap.this);
}
@J2ktIncompatible // java.io.ObjectInputStream
private void readObject(ObjectInputStream stream) throws InvalidObjectException {
throw new InvalidObjectException("Use InverseSerializedForm");
}
}
@J2ktIncompatible // serialization
private static class InverseSerializedForm implements Serializable {
private final ImmutableBiMap forward;
InverseSerializedForm(ImmutableBiMap forward) {
this.forward = forward;
}
Object readResolve() {
return forward.inverse();
}
private static final long serialVersionUID = 1;
}
}