return ((QueryEnabledValueSource) getDelegate()).getLastExpression();
        }
    }

    /**
     * Wraps an object, providing reflective access to the object graph of which the
     * supplied object is the root. Expressions like 'child.name' will translate into
     * 'rootObject.getChild().getName()' for non-boolean properties, and
     * 'rootObject.getChild().isName()' for boolean properties.
     */