The ITA Matrix allows you to search by aircraft type, though this feature is undocumented and not found in the official ITA Routing Codes help.
In the Advanced Routing Language field, you would input
/aircraft followed by the aircraft types, indicated with a
t: and using the IATA equipment codes. For example, suppose I wanted to fly from Miami to Los Angeles and was very insistent that the flights be on widebody aircraft. I could enter
and would indeed get back an all-widebody itinerary— though on the return, I'd need to fly via Honolulu to do it:
Without the type specification, the top result offers me a 737 connecting to a CRJ-900 and a return on a 757. You can use
/-aircraft for negation, too, to avoid regional jets or whichever manufacturer has aroused your ire recently.
As far as I know, this is the only publicly accessible flight search engine that allows you to search by aircraft type. Unfortunately, however, it seems you can only search for aircraft on a segment-by-segment basis. I could not coax it to search so that it returns a routing where any one segment is on a particular aircraft (if anyone has figured out the language, please suggest an edit).
So for your A380 quest, you'll need to do some legwork to identify major routes, which you can then plug back in to the ITA Multi-City search. You don't indicate where in Indonesia you are headed, but Singapore is closer to Jakarta than Hong Kong, and the link JoErNanO indicated in another answer indicates A380 flights from Frankfurt and Paris to Singapore. So, I run a search requiring an A380 on the FRA-SIN or CDG-SIN segments, then let the engine fill in the other segments as may be available:
and this returns a list of itineraries such as this:
You could then repeat the exercise looking for flights via CDG-SIN, or via HKG, or perhaps aim for multiple A380 segments via DXB, but you would need to do your comparisons in a spreadsheet or some offline listing.
There is of course a much simpler way to search for flights with designated connection points:
The trouble here is that there are numerous CDG-SIN flights on other equipment, and the time it saves you in setting up the search is more than made up in the time it takes you to sift through the larger set of non-relevant results.
Lastly, remember that ITA is just a search engine; you'll need to go elsewhere to book your desired flights.