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.util.externalizer;
022
023import java.io.IOException;
024import java.io.ObjectInput;
025import java.io.ObjectOutput;
026import java.util.LinkedHashMap;
027import java.util.Map;
028import java.util.Map.Entry;
029
030/**
031 * @author Igor SAZHNEV
032 */
033public class MapExternalizer extends DefaultExternalizer {
034
035    @Override
036    public int accept(Class<?> clazz) {
037        return Map.class.isAssignableFrom(clazz) ? 1 : -1;
038    }
039
040    @Override
041    public void readExternal(Object o, ObjectInput in) throws IOException, ClassNotFoundException, IllegalAccessException {
042        @SuppressWarnings("unchecked")
043                Map<Object, Object> map = (Map<Object, Object>)o;
044        int size = in.readInt();
045        for (int i = 0; i < size; i++) {
046                Object key = in.readObject();
047                Object value = in.readObject();
048                map.put(key, value);
049        }
050    }
051
052    @Override
053    public void writeExternal(Object o, ObjectOutput out) throws IOException, IllegalAccessException {
054        // Copy the map to limit the possibility of concurrent modification exceptions
055        // use a LinkedHashMap to keep order of elements
056        @SuppressWarnings("unchecked")
057                Map<Object, Object> map = new LinkedHashMap<Object, Object>((Map<Object, Object>)o);
058        out.writeInt(map.size());
059        for (Entry<Object, Object> entry : map.entrySet()) {
060                out.writeObject(entry.getKey());
061                out.writeObject(entry.getValue());
062        }
063    }
064}