001/*
002  GRANITE DATA SERVICES
003  Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004
005  This file is part of Granite Data Services.
006
007  Granite Data Services is free software; you can redistribute it and/or modify
008  it under the terms of the GNU Library General Public License as published by
009  the Free Software Foundation; either version 2 of the License, or (at your
010  option) any later version.
011
012  Granite Data Services is distributed in the hope that it will be useful, but
013  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014  FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015  for more details.
016
017  You should have received a copy of the GNU Library General Public License
018  along with this library; if not, see <http://www.gnu.org/licenses/>.
019*/
020
021package org.granite.messaging.amf.io.convert.impl;
022
023import java.lang.reflect.Type;
024
025import org.granite.messaging.amf.io.convert.Converter;
026import org.granite.messaging.amf.io.convert.Converters;
027import org.granite.messaging.amf.io.convert.Reverter;
028import org.granite.util.TypeUtil;
029
030import com.google.appengine.api.datastore.Key;
031import com.google.appengine.api.datastore.KeyFactory;
032
033
034public class GAEKeyConverter extends Converter implements Reverter {
035        
036        private static String KEY_CLASS = "com.google.appengine.api.datastore.Key";
037        
038    public GAEKeyConverter(Converters converters) {
039        super(converters);
040    }
041
042        @Override
043        protected boolean internalCanConvert(Object value, Type targetType) {
044        Class<?> targetClass = TypeUtil.classOfType(targetType);
045        return (
046            targetClass != Object.class && KEY_CLASS.equals(targetClass.getName()) &&
047            (value instanceof String || value == null)
048        );
049        }
050
051        @Override
052        protected Object internalConvert(Object value, Type targetType) {
053        if (value == null)
054            return null;
055        return KeyFactory.stringToKey((String)value);
056        }
057
058        public boolean canRevert(Object value) {
059                return value != null && KEY_CLASS.equals(value.getClass().getName());
060        }
061
062        public Object revert(Object value) {
063                return KeyFactory.keyToString((Key)value);
064        }
065
066}