Just a bit of trivia I picked up from a New York Times interview by Ralph Blumenthal with Thomas Hanley published August 6, 2009. (Just after the death of Budd Schulberg.)
In the article Hanley recounts how his last name was mangled in the 'Waterfront' credits into 'Handley',
Poor kid, his father was murdered on the docks for doing the right thing; Young Thomas was gypped out of a promised start to his acting career by an agent who conned the kid's Mother (after one walk-on TV appearance on the "Red Buttons Show", the Agent disappeared).
I think that Thomas had a touch of Brando's style and swagger to him. And he certainly had a gritty hard scrabble life growing up on the docks.
Check out the interview before you watch 'On the Waterfront' again!