/*
* Copyright (C) 2007 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.collect.
MapConstraints.
ConstrainedMap;
import com.google.common.primitives.
Primitives;
import java.util.
HashMap;
import java.util.
Map;
/**
* A mutable class-to-instance map backed by an arbitrary user-provided map.
* See also {@link ImmutableClassToInstanceMap}.
*
* <p>See the Guava User Guide article on <a href=
* "http://code.google.com/p/guava-libraries/wiki/NewCollectionTypesExplained#ClassToInstanceMap">
* {@code ClassToInstanceMap}</a>.
*
* @author Kevin Bourrillion
* @since 2.0 (imported from Google Collections Library)
*/
public final class
MutableClassToInstanceMap<B>
extends
ConstrainedMap<
Class<? extends B>, B>
implements
ClassToInstanceMap<B> {
/**
* Returns a new {@code MutableClassToInstanceMap} instance backed by a {@link
* HashMap} using the default initial capacity and load factor.
*/
public static <B>
MutableClassToInstanceMap<B>
create() {
return new
MutableClassToInstanceMap<B>(
new
HashMap<
Class<? extends B>, B>());
}
/**
* Returns a new {@code MutableClassToInstanceMap} instance backed by a given
* empty {@code backingMap}. The caller surrenders control of the backing map,
* and thus should not allow any direct references to it to remain accessible.
*/
public static <B>
MutableClassToInstanceMap<B>
create(
Map<
Class<? extends B>, B>
backingMap) {
return new
MutableClassToInstanceMap<B>(
backingMap);
}
private
MutableClassToInstanceMap(
Map<
Class<? extends B>, B>
delegate) {
super(
delegate,
VALUE_CAN_BE_CAST_TO_KEY);
}
private static final
MapConstraint<
Class<?>,
Object>
VALUE_CAN_BE_CAST_TO_KEY
= new
MapConstraint<
Class<?>,
Object>() {
@
Override
public void
checkKeyValue(
Class<?>
key,
Object value) {
cast(
key,
value);
}
};
@
Override
public <T extends B> T
putInstance(
Class<T>
type, T
value) {
return
cast(
type,
put(
type,
value));
}
@
Override
public <T extends B> T
getInstance(
Class<T>
type) {
return
cast(
type,
get(
type));
}
private static <B, T extends B> T
cast(
Class<T>
type, B
value) {
return
Primitives.
wrap(
type).
cast(
value);
}
private static final long
serialVersionUID = 0;
}