Factions/src/com/bukkit/mcteam/gson/JsonArrayDeserializationVisitor.java

113 lines
4.1 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 com.bukkit.mcteam.gson;
import java.lang.reflect.Array;
import java.lang.reflect.Type;
/**
* A visitor that populates fields of an object with data from its equivalent
* JSON representation
*
* @author Inderjeet Singh
* @author Joel Leitch
*/
final class JsonArrayDeserializationVisitor<T> extends JsonDeserializationVisitor<T> {
JsonArrayDeserializationVisitor(JsonArray jsonArray, Type arrayType,
ObjectNavigatorFactory factory, ObjectConstructor objectConstructor,
ParameterizedTypeHandlerMap<JsonDeserializer<?>> deserializers,
JsonDeserializationContext context) {
super(jsonArray, arrayType, factory, objectConstructor, deserializers, context);
}
@Override
@SuppressWarnings("unchecked")
protected T constructTarget() {
TypeInfo typeInfo = new TypeInfo(targetType);
if (!json.isJsonArray()) {
throw new JsonParseException("Expecting array found: " + json);
}
JsonArray jsonArray = json.getAsJsonArray();
if (typeInfo.isArray()) {
TypeInfoArray arrayTypeInfo = TypeInfoFactory.getTypeInfoForArray(targetType);
// We know that we are getting back an array of the required type, so
// this typecasting is safe.
return (T) objectConstructor.constructArray(arrayTypeInfo.getSecondLevelType(),
jsonArray.size());
}
// is a collection
return (T) objectConstructor.construct(typeInfo.getRawClass());
}
public void visitArray(Object array, Type arrayType) {
if (!json.isJsonArray()) {
throw new JsonParseException("Expecting array found: " + json);
}
JsonArray jsonArray = json.getAsJsonArray();
TypeInfoArray arrayTypeInfo = TypeInfoFactory.getTypeInfoForArray(arrayType);
for (int i = 0; i < jsonArray.size(); i++) {
JsonElement jsonChild = jsonArray.get(i);
Object child;
if (jsonChild == null || jsonChild.isJsonNull()) {
child = null;
} else if (jsonChild instanceof JsonObject) {
child = visitChildAsObject(arrayTypeInfo.getComponentRawType(), jsonChild);
} else if (jsonChild instanceof JsonArray) {
child = visitChildAsArray(arrayTypeInfo.getSecondLevelType(), jsonChild.getAsJsonArray());
} else if (jsonChild instanceof JsonPrimitive) {
child = visitChildAsObject(arrayTypeInfo.getComponentRawType(),
jsonChild.getAsJsonPrimitive());
} else {
throw new IllegalStateException();
}
Array.set(array, i, child);
}
}
// We should not implement any other method from Visitor interface since
// all other methods should be invoked on JsonObjectDeserializationVisitor
// instead.
public void startVisitingObject(Object node) {
throw new JsonParseException("Expecting array but found object: " + node);
}
public void visitArrayField(FieldAttributes f, Type typeOfF, Object obj) {
throw new JsonParseException("Expecting array but found array field " + f.getName() + ": "
+ obj);
}
public void visitObjectField(FieldAttributes f, Type typeOfF, Object obj) {
throw new JsonParseException("Expecting array but found object field " + f.getName() + ": "
+ obj);
}
public boolean visitFieldUsingCustomHandler(FieldAttributes f, Type actualTypeOfField, Object parent) {
throw new JsonParseException("Expecting array but found field " + f.getName() + ": "
+ parent);
}
public void visitPrimitive(Object primitive) {
throw new JsonParseException(
"Type information is unavailable, and the target is not a primitive: " + json);
}
}