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 * Copyright 2002 - 2007 Adobe Systems Incorporated All Rights Reserved.
 * 
 * NOTICE: All information contained herein is, and remains the property of Adobe Systems Incorporated and its suppliers, if any. The intellectual and technical concepts contained herein are
 * proprietary to Adobe Systems Incorporated and its suppliers and may be covered by U.S. and Foreign Patents, patents in process, and are protected by trade secret or copyright law. Dissemination of
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package flex.messaging.io.amf.translator.decoder;

import java.lang.reflect.Array;
import java.util.Collection;

import flex.messaging.io.TypeMarshallingContext;

/**
 * A special version of CollectionDecoder than runs a new decoder over every item before it is added to the decoded collection to restore references to any instances that may have undergone
 * translation to another type.
 * 
 * Note that tracking references is an expensive exercise and will scale poorly with larger amounts of data.
 * 
 * @author Peter Farland
 * 
 * @exclude
 */
public class ReferenceAwareCollectionDecoder extends CollectionDecoder
{
    /**
     * We want to iterate through all of the contents of the Collection to check for references that need to be restored and translations that may still be required (in the case of typed ASObjects).
     * 
     * Return false to ensure we create a new collection and copy all of the contents.
     */
    @Override
    protected boolean isSuitableCollection(Object encodedObject, Class desiredClass)
    {
        return false;
    }

    @Override
    protected Collection decodeCollection(Collection shell, Object encodedObject)
    {
        Collection decodedCollection = shell;
        Object decodedObject = null;
        Object obj = null;

        TypeMarshallingContext context = TypeMarshallingContext.getTypeMarshallingContext();
        ActionScriptDecoder decoder = null;

        if (encodedObject instanceof String)
        {
            encodedObject = ((String) encodedObject).toCharArray();
        }
        else
        {
            if (encodedObject instanceof Collection)
            {
                encodedObject = ((Collection) encodedObject).toArray();
            }

            context.getKnownObjects().put(encodedObject, shell);
        }

        int len = Array.getLength(encodedObject);

        for (int i = 0; i < len; i++)
        {
            obj = Array.get(encodedObject, i);

            if (obj == null)
            {
                decodedCollection.add(null);
            }
            else
            {
                // Check whether we need to restore a client
                // side reference to a known object
                Object ref = null;

                if (canUseByReference(obj))
                    ref = context.getKnownObjects().get(obj);

                if (ref == null)
                {
                    decoder = DecoderFactory.getReferenceAwareDecoder(obj, obj.getClass());
                    decodedObject = decoder.decodeObject(obj, obj.getClass());

                    if (canUseByReference(decodedObject))
                    {
                        context.getKnownObjects().put(obj, decodedObject);
                    }
                }
                else
                {
                    decodedObject = ref;
                }

                decodedCollection.add(decodedObject);
            }
        }

        return decodedCollection;
    }
}