From Muppet Wiki

Al Hirt (1922-1999) was a famous trumpeter and bandleader. His 1964 hit "Java" was used as the soundtrack to a recurring Muppet sketch that was performed on several variety shows as well as episode 122 of The Muppet Show.

Hirt also hosted the variety series Fanfare, on which he chatted up a Two-Headed Muppet Monster in 1965.