function mxPropertiesManager() {
                        /**
                         * Map with the document's colors.<br/>
                         * The key is the index number and the value is the hex representation of the color.
                         */
                        /*private*/ this.colorElementMap = ({});
                        /**
                         * Map with the document's fonts.<br/>
                         * The key is the ID and the value is the name of the font.
                         */
                        /*private*/ this.fontElementMap = ({});
                    }
This is a singleton class that stores various global properties to document.<br/>
The properties are:
<ul>
<li>
document's colors
</li>
<li>
document's fonts
</li>
<li>
default text style
</li>
<li>
default line style
</li>
<li>
default fill style
</li>
</ul>
@class