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    import java.lang.reflect.WildcardType;
025    import java.util.Collection;
026    
027    import org.granite.messaging.amf.io.convert.Converter;
028    import org.granite.messaging.amf.io.convert.Converters;
029    import org.granite.messaging.amf.io.convert.IllegalConverterArgumentException;
030    import org.granite.util.TypeUtil;
031    import org.granite.util.CollectionUtil;
032    
033    /**
034     * @author Franck WOLFF
035     */
036    public class Collection2Collection extends Converter {
037    
038        public Collection2Collection(Converters converters) {
039            super(converters);
040        }
041    
042        @Override
043            protected boolean internalCanConvert(Object value, Type targetType) {
044    
045            Type targetComponentType = CollectionUtil.getComponentType(targetType);
046            if (targetComponentType == null)
047                return false; // not a collection.
048    
049            if (value == null)
050                return true;
051    
052            if (!(value instanceof Collection<?>))
053                return false;
054    
055            if (targetComponentType.equals(Object.class) || targetComponentType instanceof WildcardType)
056                return true;
057    
058            Converter itemConverter = null;
059            for (Object item : (Collection<?>)value) {
060    
061                if (itemConverter == null)
062                    itemConverter = converters.getConverter(item, targetComponentType);
063                else if (!itemConverter.canConvert(item, targetComponentType))
064                    itemConverter = converters.getConverter(item, targetComponentType);
065    
066                if (itemConverter == null)
067                    return false;
068            }
069    
070            return true;
071        }
072    
073        @Override
074            protected Object internalConvert(Object value, Type targetType) {
075    
076            if (value == null)
077                return null;
078    
079            if (value instanceof Collection<?>) {
080                Collection<?> c = (Collection<?>)value;
081    
082                Type targetComponentType = CollectionUtil.getComponentType(targetType);
083                if (targetComponentType != null) {
084    
085                    Class<?> targetClass = TypeUtil.classOfType(targetType);
086                    if (targetClass.isInstance(value)) {
087                            if (targetComponentType.equals(Object.class) || targetComponentType instanceof WildcardType)
088                                    return value;
089                            
090                            if (targetComponentType instanceof Class<?>) {
091                                    boolean check = true;
092                                    for (Object e : c) {
093                                            if (!((Class<?>)targetComponentType).isInstance(e)) {
094                                                    check = false;
095                                                    break;
096                                            }
097                                    }
098                                    if (check)
099                                            return value;
100                            }
101                    }
102    
103                    Collection<Object> targetInstance = null;
104                    try {
105                        targetInstance = CollectionUtil.newCollection(targetClass, c.size());
106                    } catch (Exception e) {
107                        throw new IllegalConverterArgumentException(this, value, targetType, e);
108                    }
109    
110                    Converter itemConverter = null;
111                    for (Object item : c) {
112    
113                        if (itemConverter == null)
114                            itemConverter = converters.getConverter(item, targetComponentType);
115                        else if (!itemConverter.canConvert(item, targetComponentType))
116                            itemConverter = converters.getConverter(item, targetComponentType);
117    
118                        if (itemConverter == null)
119                            throw new IllegalConverterArgumentException(this, value, targetType);
120    
121                        targetInstance.add(itemConverter.convert(item, targetComponentType));
122                    }
123    
124                    return targetInstance;
125                }
126            }
127    
128            throw new IllegalConverterArgumentException(this, value, targetType);
129        }
130    }