How you feel about the revival of "Little Johnny Jones," which opened yesterday afternoon in the Kennedy Center Opera House, will very likely correspond to how you feel about Donny Osmond. More closely, in fact, than you might first imagine.

This is not just because Osmond stars in the revival of George M. Cohan's 1904 musical, as a brash jockey who goes to England to participate in the British derby, loses the race and, temporarily, both his honor and his girlfriend. Nor is it just because Osmond gets to sing "I'm a Yankee Doodle Dandy" and "Give My Regards to Broadway," the two most celebrated songs in the show, here whipped up into bountiful production numbers.

No, this coincidence has something to do with the very nature of musical comedy, before Rodgers and Hammerstein came along and turned it into a coherent story-telling form. In Cohan's time, musicals were made for their stars --shaped and tailored to their specifications and their idiosyncracies. Cohan boldly wrote "Little Johnny Jones" for himself, in fact, and it not only made him a star, it helped establish his feisty, flag-waving persona. Back then, if the plots didn't always make a great deal of sense, and the songs sometimes came very nearly out of nowhere, what did it matter? The star was there to give the show its ultimate shape, and his personality was the glue that held things together.

Whether Osmond has the power as a stage performer to fulfill that function in our day and age, I am not entirely sure. To me, he seems like a hard-working young man who takes his responsibilities very seriously. He has teeth as white as the white suit he sports in his first scene, smiles frequently, throws himself into his tap dances with schoolboy zest, and smiles some more. He is learning to strut -- his character being a red, white and blue strutter from the starting gun -- and he tosses off such nuggets of Cohanesque patriotism as "French pastry ain't worth 30 cents compared to American apple pie" with a fair degree of assurance. In short, in this, his soon-to-be Broadway debut, Osmond is not covering himself with shame.

By the same token, he is not yet galvanizing "Little Johnny Jones," and that, I fear, is the obligation of whatever actor decides to step into Cohan's shoes. Right now, Osmond appears to be pulled along by the show; he doesn't propel it. Choreographer Dan Siretta has come up with some fancy interlocking footwork for the company in "American Rag" and the inevitable kick-line for "Give My Regards to Broadway." With great good will, Osmond joins in. But joining in may not be enough.

"Little Johnny Jones" has lots going for it -- a bright, vigorous cast; some immensely cheerful sets and costumes that seem to have just tumbled out of a paint-box; an ocean liner both at dock and at sea, and some horses on the hoof and at rest; and finally, a rustic Fourth of July impudence that prizes America first and every other country last. Still, it is a fairly silly show. Alfred Uhry has been called in to tidy up Cohan's original book, but even tidied up, the story is a dithering mishmash. The heroine (the charming Maureen Brennan) is obliged to disguise herself alternately as an English earl, a French coquette and a newsboy. The villain (Peter Van Norden) doesn't get to twirl his mustache, but otherwise his perfidy is on a par with the wicked rent collector's. A matronly aunt (Anna McNeely) goes giddy at the mere shadow of European aristocracy. And a Chinese man named Sing-Song scurries about the stage, inscrutably. Under the simple-minded circumstances, it is unlikely that you will care deeply whether or not Little Johnny Jones vindicates his honor and wins the girl.

But if the show is not simply to diddle away the hours with harmless, empty nostalgia, we have to be made to care. And that is the star's job. If he is engaging enough of disposition, arresting enough in his musical skills, and forceful enough in the belief he brings to a cardboard world, then we, too, will go along. Outdated conventions will seem less idiotic, songs tumbling from the skies will seem less arbitrary, and corny jokes will seem less threadbare.

That is why, I suggest, your feelings about Osmond will pretty much be your feelings about the show. Across the aisle from me, two teen-age girls and a middle-aged matron applauded him at every turn and emitted audible moans of ecstasy when he embraced the heroine. For them, I suspect, "Little Johnny Jones" offered no problems in credibility whatsoever.

Those who are less disposed toward the star may find that "Little Johnny Jones" consists of lots of pretty decorations looking for something to hang themselves on.

LITTLE JOHNNY JONES. Book, music and lyrics by George M. Cohan. Adapted by Alfred Uhry. Directed by Gerald Gutierrez; choreography, Dan Siretta; sets, Robert Randolph; costumes, David Toser; musical direction, Lynn Crigler; with Donny Osmond, Maureen Brennan, Peter Van Norden, Jane Galloway, Anna McNeely, Jack Bittner, Tom Rolfing, Ernie Sabella. At the Kennedy Center Opera House through Feb. 7.