/*
|
* Copyright (C) 2011 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 cn.emay.sdk.util.json.gson.internal.bind;
|
|
import java.io.IOException;
|
import java.lang.reflect.Type;
|
import java.lang.reflect.TypeVariable;
|
|
import cn.emay.sdk.util.json.gson.Gson;
|
import cn.emay.sdk.util.json.gson.TypeAdapter;
|
import cn.emay.sdk.util.json.gson.reflect.TypeToken;
|
import cn.emay.sdk.util.json.gson.stream.JsonReader;
|
import cn.emay.sdk.util.json.gson.stream.JsonWriter;
|
|
final class TypeAdapterRuntimeTypeWrapper<T> extends TypeAdapter<T> {
|
private final Gson context;
|
private final TypeAdapter<T> delegate;
|
private final Type type;
|
|
TypeAdapterRuntimeTypeWrapper(Gson context, TypeAdapter<T> delegate, Type type) {
|
this.context = context;
|
this.delegate = delegate;
|
this.type = type;
|
}
|
|
@Override
|
public T read(JsonReader in) throws IOException {
|
return delegate.read(in);
|
}
|
|
@SuppressWarnings({ "rawtypes", "unchecked" })
|
@Override
|
public void write(JsonWriter out, T value) throws IOException {
|
// Order of preference for choosing type adapters
|
// First preference: a type adapter registered for the runtime type
|
// Second preference: a type adapter registered for the declared type
|
// Third preference: reflective type adapter for the runtime type (if it is a
|
// sub class of the declared type)
|
// Fourth preference: reflective type adapter for the declared type
|
|
TypeAdapter chosen = delegate;
|
Type runtimeType = getRuntimeTypeIfMoreSpecific(type, value);
|
if (runtimeType != type) {
|
TypeAdapter runtimeTypeAdapter = context.getAdapter(TypeToken.get(runtimeType));
|
if (!(runtimeTypeAdapter instanceof ReflectiveTypeAdapterFactory.Adapter)) {
|
// The user registered a type adapter for the runtime type, so we will use that
|
chosen = runtimeTypeAdapter;
|
} else if (!(delegate instanceof ReflectiveTypeAdapterFactory.Adapter)) {
|
// The user registered a type adapter for Base class, so we prefer it over the
|
// reflective type adapter for the runtime type
|
chosen = delegate;
|
} else {
|
// Use the type adapter for runtime type
|
chosen = runtimeTypeAdapter;
|
}
|
}
|
chosen.write(out, value);
|
}
|
|
/**
|
* Finds a compatible runtime type if it is more specific
|
*/
|
private Type getRuntimeTypeIfMoreSpecific(Type type, Object value) {
|
if (value != null && (type == Object.class || type instanceof TypeVariable<?> || type instanceof Class<?>)) {
|
type = value.getClass();
|
}
|
return type;
|
}
|
}
|