I would keep in mind that, on average, a person installing a one-wire network is more technically capable then someone who might install a router. Java compatibillity and other potential problems might not be that big an issue.
But I would like to make another distinction from a router: a router almost never has to present "live" data to the user. Live data can be a problem for an HTML-based system (ask any HomeSeer2 user).
The ability to display one-wire data, like temperatures, in real-time may be worth the extra investment in Java.