| /* |
| * Copyright (C) 2012 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.reflect; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| |
| import com.google.common.annotations.Beta; |
| import com.google.common.base.Function; |
| import com.google.common.collect.ForwardingMap; |
| import com.google.common.collect.ForwardingMapEntry; |
| import com.google.common.collect.ForwardingSet; |
| import com.google.common.collect.Iterators; |
| import com.google.common.collect.Maps; |
| |
| import java.util.Iterator; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import javax.annotation.Nullable; |
| |
| /** |
| * A mutable type-to-instance map. |
| * See also {@link ImmutableTypeToInstanceMap}. |
| * |
| * @author Ben Yu |
| * @since 13.0 |
| */ |
| @Beta |
| public final class MutableTypeToInstanceMap<B> extends ForwardingMap<TypeToken<? extends B>, B> |
| implements TypeToInstanceMap<B> { |
| |
| private final Map<TypeToken<? extends B>, B> backingMap = Maps.newHashMap(); |
| |
| @Nullable |
| @Override |
| public <T extends B> T getInstance(Class<T> type) { |
| return trustedGet(TypeToken.of(type)); |
| } |
| |
| @Nullable |
| @Override |
| public <T extends B> T putInstance(Class<T> type, @Nullable T value) { |
| return trustedPut(TypeToken.of(type), value); |
| } |
| |
| @Nullable |
| @Override |
| public <T extends B> T getInstance(TypeToken<T> type) { |
| return trustedGet(type.rejectTypeVariables()); |
| } |
| |
| @Nullable |
| @Override |
| public <T extends B> T putInstance(TypeToken<T> type, @Nullable T value) { |
| return trustedPut(type.rejectTypeVariables(), value); |
| } |
| |
| /** Not supported. Use {@link #putInstance} instead. */ |
| @Override public B put(TypeToken<? extends B> key, B value) { |
| throw new UnsupportedOperationException("Please use putInstance() instead."); |
| } |
| |
| /** Not supported. Use {@link #putInstance} instead. */ |
| @Override public void putAll(Map<? extends TypeToken<? extends B>, ? extends B> map) { |
| throw new UnsupportedOperationException("Please use putInstance() instead."); |
| } |
| |
| @Override public Set<Entry<TypeToken<? extends B>, B>> entrySet() { |
| return UnmodifiableEntry.transformEntries(super.entrySet()); |
| } |
| |
| @Override protected Map<TypeToken<? extends B>, B> delegate() { |
| return backingMap; |
| } |
| |
| @SuppressWarnings("unchecked") // value could not get in if not a T |
| @Nullable |
| private <T extends B> T trustedPut(TypeToken<T> type, @Nullable T value) { |
| return (T) backingMap.put(type, value); |
| } |
| |
| @SuppressWarnings("unchecked") // value could not get in if not a T |
| @Nullable |
| private <T extends B> T trustedGet(TypeToken<T> type) { |
| return (T) backingMap.get(type); |
| } |
| |
| private static final class UnmodifiableEntry<K, V> extends ForwardingMapEntry<K, V> { |
| |
| private final Entry<K, V> delegate; |
| |
| static <K, V> Set<Entry<K, V>> transformEntries(final Set<Entry<K, V>> entries) { |
| return new ForwardingSet<Map.Entry<K, V>>() { |
| @Override protected Set<Entry<K, V>> delegate() { |
| return entries; |
| } |
| @Override public Iterator<Entry<K, V>> iterator() { |
| return UnmodifiableEntry.transformEntries(super.iterator()); |
| } |
| @Override public Object[] toArray() { |
| return standardToArray(); |
| } |
| @Override public <T> T[] toArray(T[] array) { |
| return standardToArray(array); |
| } |
| }; |
| } |
| |
| private static <K, V> Iterator<Entry<K, V>> transformEntries(Iterator<Entry<K, V>> entries) { |
| return Iterators.transform(entries, new Function<Entry<K, V>, Entry<K, V>>() { |
| @Override public Entry<K, V> apply(Entry<K, V> entry) { |
| return new UnmodifiableEntry<K, V>(entry); |
| } |
| }); |
| } |
| |
| private UnmodifiableEntry(java.util.Map.Entry<K, V> delegate) { |
| this.delegate = checkNotNull(delegate); |
| } |
| |
| @Override protected Entry<K, V> delegate() { |
| return delegate; |
| } |
| |
| @Override public V setValue(V value) { |
| throw new UnsupportedOperationException(); |
| } |
| } |
| } |