Saber-Factions/src/org/mcteam/factions/gson/MappedObjectConstructor.java
2011-06-22 18:40:56 -05:00

78 lines
2.7 KiB
Java

/*
* Copyright (C) 2008 Google Inc.
*
* 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 org.mcteam.factions.gson;
import org.mcteam.factions.gson.internal.$Gson$Types;
import java.lang.reflect.Array;
import java.lang.reflect.Type;
/**
* This class contains a mapping of all the application specific
* {@link InstanceCreator} instances. Registering an {@link InstanceCreator}
* with this class will override the default object creation that is defined
* by the ObjectConstructor that this class is wrapping. Using this class
* with the JSON framework provides the application with "pluggable" modules
* to customize framework to suit the application's needs.
*
* @author Joel Leitch
*/
final class MappedObjectConstructor implements ObjectConstructor {
private static final UnsafeAllocator unsafeAllocator = UnsafeAllocator.create();
private static final DefaultConstructorAllocator defaultConstructorAllocator =
new DefaultConstructorAllocator(500);
private final ParameterizedTypeHandlerMap<InstanceCreator<?>> instanceCreatorMap;
public MappedObjectConstructor(
ParameterizedTypeHandlerMap<InstanceCreator<?>> instanceCreators) {
instanceCreatorMap = instanceCreators;
}
@SuppressWarnings("unchecked")
public <T> T construct(Type typeOfT) {
InstanceCreator<T> creator = (InstanceCreator<T>) instanceCreatorMap.getHandlerFor(typeOfT);
if (creator != null) {
return creator.createInstance(typeOfT);
}
return (T) constructWithAllocators(typeOfT);
}
public Object constructArray(Type type, int length) {
return Array.newInstance($Gson$Types.getRawType(type), length);
}
@SuppressWarnings({"unchecked", "cast"})
private <T> T constructWithAllocators(Type typeOfT) {
try {
Class<T> clazz = (Class<T>) $Gson$Types.getRawType(typeOfT);
T obj = defaultConstructorAllocator.newInstance(clazz);
return (obj == null)
? unsafeAllocator.newInstance(clazz)
: obj;
} catch (Exception e) {
throw new RuntimeException(("Unable to invoke no-args constructor for " + typeOfT + ". "
+ "Register an InstanceCreator with Gson for this type may fix this problem."), e);
}
}
@Override
public String toString() {
return instanceCreatorMap.toString();
}
}