The 47-year-old talk show host has his own 'barn bar' in his West Hollywood home and was happy to throw its doors open for his pal and some friends on Monday (03.08.15) to celebrate his last days of a single man ahead of his recent wedding to Jennifer Aniston at their Bel Air home on Wednesday (05.08.15), Us Weekly reports.
While he hosted the party, Jimmy wasn't the 'Leftovers' actor's Best Man.
Instead, that honour went to Jason's close friend and tattoo artist, Scott Campbell, while Courteney Cox was Jennifer's maid of honour.
The couple went to great lengths to keep their wedding - which was attended by stars including Jimmy, Emily Blunt and her husband John Krasinski, Chelsea Handler and Ellen Degeneres - under wraps and even scrapped their original plan to get married abroad for added security.
A source told the New York Post newspaper's Page Six column: ''Jennifer and Justin have been planning an August wedding, but it was very, very top-secret. They had talked about getting married abroad, but decided on their home for privacy while allowing their closest friends to be there.''
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