You can’t. The original ‘Java Man’ bones were lost during WWII. I think they were in someone’s suitcase, taken to Nanking - just in time for the arrival of the Japanese who slaughtered everbody they could in the city.
So was the original the same as those found today? Who knows?
Nope. You're thinking of "Peking Man". Although both are the same species: Homo erectus.