Jessie J had blasted two-faced stars.

The 'Price Tag' singer has slated other artists who put on a persona on stage, appearing likeable in public despite being ''miserable'' and unprofessional when they're hidden from the public.

She told The Observer newspaper: ''I won't mention no names, but I've met artists who are so 'on it' when they're on camera, or on stage, so the audience and the media thinks that they're like that, and the you see them come off stage, and they're mean, they're miserable and they're late.

''I want everybody to think I'm a hard worker as an aunt, a sister, a friend, a daughter, a niece, everything. I want to be great at every role, because every role in my life is as important as being Jessie J.''

The 25-year-old musician has not had an alcoholic drink since she was 15, and credited her career with staying ''clean'' and relatively calm compared to more outrageous celebrities.

She said: ''I like my life to be pure and clean and organised, and I like to have had eight hours' sleep a night.

''I honestly don't think I'd be as successful if I was a party animal. Because I don't think my personality would be as focused and open as it is.''