From the magazine America, July 1, 2009:
Father Corridan: Karl Malden's "Waterfront" Inspiration
“News today that Karl Malden died at the age of 97 (I liked him best in "The Streets of San Francisco," where he played the gruff-but- unflappable cop to Michael Douglas's hotheaded rookie), reminded me of his seminal role as Fr. Pete Barry, the priest in the film "On the Waterfront."  The person upon whom that character was based was the Jesuit priest John Corridan.  Fordham University professor James Fisher is hard at work on a book on the life and work of this astonishing man. Below is a short piece by Fisher that was published in Company in 2003.   (I'll link to the original piece "Waterfront Priest" here, but reprint most of it below, with a tip of the hat to Company, the magazine for Jesuits and their friends, since the original site has some photos missing.)  Also, here's another piece about the man in The Irish Echo.  Finally, believe it or not, Mr. Malden died on the 25th anniversary of Fr. Corridan's death, July 1, 1984.
--THE CLASSIC 1954 film, On the Waterfront, is renowned among film buffs for the legendary performance of Marlon Brando as longshoreman Terry Malloy, the gritty Hoboken, N.J., locations, and the brilliant direction of Elia Kazan. Far less well known–even among dedicated fans of the Academy Award-winning film–is that the inspiration for the film, Fr. John Corridan, was a Jesuit who graduated from Regis High School in New York in 1928.”
Read More: 
https://www.americamagazine.org/content/all-things/fr-corridan-karl-maldens-waterfront-inspiration