Deserializer.java

/*
 * RED5 Open Source Flash Server - http://code.google.com/p/red5/
 * 
 * Copyright 2006-2012 by respective authors (see below). All rights reserved.
 * 
 * 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.red5.io.object;

import java.lang.reflect.Type;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * The Deserializer class reads data input and handles the data according to the core data types
 *
 * @author The Red5 Project (red5@osflash.org)
 * @author Luke Hubbard, Codegent Ltd (luke@codegent.com)
 */
public class Deserializer {

	// Initialize Logging
	private static final Logger log = LoggerFactory.getLogger(Deserializer.class);

	/**
	 * Deserializes the input parameter and returns an Object which must then be cast to a core data type
	 * 
	 * @param <T> type
	 * @param in input
	 * @param target target
	 * @return Object object
	 */
	@SuppressWarnings({ "unchecked", "rawtypes" })
	public <T> T deserialize(Input in, Type target) {
		byte type = in.readDataType();
		log.trace("Type: {} target: {}", type, (target != null ? target.toString() : "Target not specified"));
		while (type == DataTypes.CORE_SKIP) {
			type = in.readDataType();
			log.trace("Type (skip): {}", type);
		}
		log.debug("Datatype: {}", DataTypes.toStringValue(type));
		Object result;
		switch (type) {
			case DataTypes.CORE_NULL:
				result = in.readNull(target);
				break;
			case DataTypes.CORE_BOOLEAN:
				result = in.readBoolean(target);
				break;
			case DataTypes.CORE_NUMBER:
				result = in.readNumber(target);
				break;
			case DataTypes.CORE_STRING:
				if (target != null && ((Class) target).isEnum()) {
					log.warn("Enum target specified");
					String name = in.readString(target);
					result = Enum.valueOf((Class) target, name);
				} else {
					result = in.readString(target);
				}
				break;
			case DataTypes.CORE_DATE:
				result = in.readDate(target);
				break;
			case DataTypes.CORE_ARRAY:
				result = in.readArray(this, target);
				break;
			case DataTypes.CORE_MAP:
				result = in.readMap(this, target);
				break;
			case DataTypes.CORE_XML:
				result = in.readXML(target);
				break;
			case DataTypes.CORE_OBJECT:
				result = in.readObject(this, target);
				break;
			case DataTypes.CORE_BYTEARRAY:
				result = in.readByteArray(target);
				break;
			case DataTypes.CORE_VECTOR_INT:
				result = in.readVectorInt();
				break;
			case DataTypes.CORE_VECTOR_UINT:
				result = in.readVectorUInt();
				break;
			case DataTypes.CORE_VECTOR_NUMBER:
				result = in.readVectorNumber();
				break;
			case DataTypes.CORE_VECTOR_OBJECT:
				result = in.readVectorObject();
				break;
			case DataTypes.OPT_REFERENCE:
				result = in.readReference(target);
				break;
			default:
				result = in.readCustom(target);
				break;
		}
		return (T) postProcessExtension(result, target);
	}

	/**
	 * Post processes the result
	 * TODO Extension Point
	 * @param result result
	 * @param target target
	 * @return object
	 */
	protected Object postProcessExtension(Object result, Type target) {
		// does nothing at the moment, but will later!
		return result;
	}

}