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diff --git a/src/js/io/mxCodecRegistry.js b/src/js/io/mxCodecRegistry.js
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+++ b/src/js/io/mxCodecRegistry.js
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+/**
+ * $Id: mxCodecRegistry.js,v 1.12 2010-04-30 13:18:21 gaudenz Exp $
+ * Copyright (c) 2006-2010, JGraph Ltd
+ */
+var mxCodecRegistry =
+{
+	/**
+	 * Class: mxCodecRegistry
+	 *
+	 * Singleton class that acts as a global registry for codecs.
+	 *
+	 * Adding an <mxCodec>:
+	 *
+	 * 1. Define a default codec with a new instance of the 
+	 * object to be handled.
+	 *
+	 * (code)
+	 * var codec = new mxObjectCodec(new mxGraphModel());
+	 * (end)
+	 *
+	 * 2. Define the functions required for encoding and decoding
+	 * objects.
+	 *
+	 * (code)
+	 * codec.encode = function(enc, obj) { ... }
+	 * codec.decode = function(dec, node, into) { ... }
+	 * (end)
+	 *
+	 * 3. Register the codec in the <mxCodecRegistry>.
+	 *
+	 * (code)
+	 * mxCodecRegistry.register(codec);
+	 * (end)
+	 *
+	 * <mxObjectCodec.decode> may be used to either create a new 
+	 * instance of an object or to configure an existing instance, 
+	 * in which case the into argument points to the existing
+	 * object. In this case, we say the codec "configures" the
+	 * object.
+	 * 
+	 * Variable: codecs
+	 *
+	 * Maps from constructor names to codecs.
+	 */
+	codecs: [],
+	
+	/**
+	 * Variable: aliases
+	 *
+	 * Maps from classnames to codecnames.
+	 */
+	aliases: [],
+
+	/**
+	 * Function: register
+	 *
+	 * Registers a new codec and associates the name of the template
+	 * constructor in the codec with the codec object.
+	 *
+	 * Parameters:
+	 *
+	 * codec - <mxObjectCodec> to be registered.
+	 */
+	register: function(codec)
+	{
+		if (codec != null)
+		{
+			var name = codec.getName();
+			mxCodecRegistry.codecs[name] = codec;
+			
+			var classname = mxUtils.getFunctionName(codec.template.constructor);
+
+			if (classname != name)
+			{
+				mxCodecRegistry.addAlias(classname, name);
+			}
+		}
+
+		return codec;
+	},
+
+	/**
+	 * Function: addAlias
+	 *
+	 * Adds an alias for mapping a classname to a codecname.
+	 */
+	addAlias: function(classname, codecname)
+	{
+		mxCodecRegistry.aliases[classname] = codecname;
+	},
+
+	/**
+	 * Function: getCodec
+	 *
+	 * Returns a codec that handles objects that are constructed
+	 * using the given constructor.
+	 *
+	 * Parameters:
+	 *
+	 * ctor - JavaScript constructor function. 
+	 */
+	getCodec: function(ctor)
+	{
+		var codec = null;
+		
+		if (ctor != null)
+		{
+			var name = mxUtils.getFunctionName(ctor);
+			var tmp = mxCodecRegistry.aliases[name];
+			
+			if (tmp != null)
+			{
+				name = tmp;
+			}
+			
+			codec = mxCodecRegistry.codecs[name];
+			
+			// Registers a new default codec for the given constructor
+			// if no codec has been previously defined.
+			if (codec == null)
+			{
+				try
+				{
+					codec = new mxObjectCodec(new ctor());
+					mxCodecRegistry.register(codec);
+				}
+				catch (e)
+				{
+					// ignore
+				}
+			}
+		}
+		
+		return codec;
+	}
+
+};