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    
021    package org.granite.messaging.amf.io.convert.impl;
022    
023    import java.lang.reflect.Type;
024    
025    import org.granite.messaging.amf.io.convert.Converter;
026    import org.granite.messaging.amf.io.convert.Converters;
027    import org.granite.messaging.amf.io.convert.Reverter;
028    import org.granite.util.ClassUtil;
029    
030    import com.google.appengine.api.datastore.Key;
031    import com.google.appengine.api.datastore.KeyFactory;
032    
033    
034    public 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 = ClassUtil.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    }