Java wood?

[capricorn30]

I'm sorry, I'm sure this question is asked all the time!

The 'natural' set ups that some of you have are just lovely! There seems to be a mix of wood, cork and stone as levels/tunnels/ramps and I was wondering where these come from, and which are hamster safe?

Some of my local pet shops sell pieces of java wood, and zooplus do a selection of 'natural rocks and roots' for aquariums, but I wasn't sure if these were suitable? There's also a few different fake rough plastic 'rocks' for bowls/hides designed for reptiles - I'm using a large, low, flat hide as a nest area and extra level atm!