public XMLTagLibrary() {
registerTag("out", ExprTag.class);
registerTag("if", IfTag.class);
registerTag("forEach", ForEachTag.class);
registerTag("parse", ParseTag.class);
registerTag("set", SetTag.class);
registerTag("transform", TransformTag.class);
registerTag("param", ParamTag.class);
registerTag("expr", ExprTag.class);
registerTag("element", ElementTag.class);
registerTag("attribute", AttributeTag.class);
registerTag("replaceNamespace", ReplaceNamespaceTag.class);
registerTag("copy", CopyTag.class);
registerTag("copyOf", CopyOfTag.class);
registerTag("comment", CommentTag.class);
registerTag("doctype", DoctypeTag.class);
registerTag("sort", SortTag.class);
this.jexlFactory = new JexlExpressionFactory();
}