DocumentSet docs,
	public Sequence eval(		DocumentSet docs,		Sequence contextSequence,		Item contextItem)		throws XPathException {		// request object is read from global variable $request		Variable var = context.resolveVariable("session");		if(var.getValue() == null)			throw new XPathException("Session not set");		if(var.getValue().getItemType() != Type.JAVA_OBJECT)			throw new XPathException("Variable $session is not bound to an Java object.");		JavaObjectValue value = (JavaObjectValue) var.getValue().itemAt(0);				// get attribute name parameter		String attrib = getArgument(0).eval(docs, contextSequence, contextItem).getStringValue();				if(value.getObject() instanceof Session)			return cocoonSessionAttribute(attrib, (Session)value.getObject());		else if(value.getObject() instanceof HttpSession)			return httpSessionAttribute(attrib, (HttpSession)value.getObject());		else			throw new XPathException("Type error: variable $session is not bound to a session object");	}