Jerry Herman is at home in his mansion high above the Bel Air Country Club, remembering some of the ever-so-buoyant songs that made him rich. It's one of those perfect Southern California mornings, with just enough moisture in the air to lend an impressionistic haze to the lush landscaping. Sunlight streams through a picture window behind him.

A lyric he crafted in 1961 for "Milk and Honey" springs into his mind:

Let's not waste a moment

Let's not lose a day

There's a short forever

Not too far away.

"I was in my twenties when I wrote that, the pink of health," he marvels, a faint tone of surprise in his voice. "I didn't know what it really meant."

And now another, from "I'll Be Here Tomorrow," which he wrote in 1979 for "The Grand Tour":

I'll be here tomorrow,

Alive and well and thriving.

I'll be here tomorrow,

It's simply called surviving.

He ponders the implications, then says, "Who would have thought that song would have such a profound meaning for me today?"

Herman's eyes mist over and he turns away, his boyish face showing few signs that he is 62 -- and no sign at all that, more than a decade ago, he was exposed to the AIDS virus.

Jerry Herman is Broadway's foremost practitioner of the power of positive song-writing. He has spent his career assuring audiences that these are "The Best of Times" (in "La Cage aux Folles") and if they're not, well, "I Don't Want to Know" ("Dear World"). He has urged them to "Put on Your Sunday Clothes" ("Hello, Dolly!") and "Open a New Window" ("Mame"). He has reminded them that "It's Today" ("Mame" again) -- and what better occasion to "Tap Your Troubles Away" ("Mack and Mabel")?

He may not have Cole Porter's sophistication or Stephen Sondheim's dizzying intellect, Larry Hart's wry irony or Oscar Hammerstein's poetic simplicity. But no composer-lyricist can match him at filling a playhouse with sheer, undiluted happiness. He is the smile button made flesh.

His indestructible optimism has earned him a king's fortune. It has also earned him a reputation for being shallow and old-fashioned.

And it may just be what's saving his life. Alive, Well, Thriving

"The fascinating thing," he says, "is that this is the sort of stuff that has always come out of me." But now he wonders if it wasn't all a kind of preparation -- schooling for his own survival. Eleven years ago he tested positive for the AIDS virus. Six years ago his lover died from the scourge. All around him, these days, he can't help noticing what he never saw when he was younger -- sickness, fear and mortality.

On this breathtakingly lovely morning, Herman is sitting at the baronial table that serves as a desk in the office of his home. Two and a half years ago he moved here from New York, fed up with Eastern winters and the declining state of Broadway. If he no longer resembles the sleek figure in the glamorous oil painting that hangs in his two-story library, it's probably because he never really did. But he is trim and energetic, and his features still have that slightly elfin quality that, for a long time, made him appear a decade younger than he really was.

AIDS is not a word that crops up often in his conversation. Not that Herman isn't candid about his condition or his homosexuality. As he notes, he is the person who wrote "I Am What I Am" ("La Cage") and anything less than candor would make "my whole life a sham." He resorts to a kind of semantic cushioning, however -- preferring to talk about "this problem" or simply "it." His doctors are treating him with the latest experimental procedures, and he has yet to suffer an opportunistic infection. But when he says, "This has really put my whole life and work in focus," the unspoken subject is unavoidably clear.

"When you're first diagnosed as HIV-positive, your head spins and you think, I'm going to be next and I haven't done half the things I wanted to," Herman says. "The big fear is finding yourself in a hospital bed with tubes up your nose. I honestly panicked.

"But it's not necessary," he continues. "It's not the end of the world. You can go on with a life. People should know that. Look at me. I've had this for 11, maybe 12 years. I'm happy, I'm healthy and I've got four shows in the works."

After a long fallow period, he has just completed the score for a new musical, "Mrs. Santa Claus," which CBS plans to air as a Christmas special starring Angela Lansbury in 1996. In it, that hitherto unsung wife, long relegated to the kitchen at the North Pole, hitches up her skirts and her sleigh, travels to New York circa 1910, and manages to get a life for herself -- not unlike such determined Herman heroines as Mame Dennis and Dolly Levi.

"Mack and Mabel," the 1974 flop about the ill-fated romance of Mack Sennett and Mabel Normand that has always been dear to Herman's heart, is opening in London this fall with a new, more upbeat book which, Herman believes, will finally put it in the winner's circle. He is in the midst of serious discussion for a television production of "Mame." Meanwhile, he's supervising the 30th-anniversary tour of "Hello, Dolly!" that has been mopping up around the country and recently grossed a staggering $840,000 for a single week in Costa Mesa, Calif. (The production arrives Sept. 12 at the Kennedy Center.)

"In many ways, Jerry is still this kid who's hoping to sell his first song," observes Mark Saltzman, the 43-year-old writer who collaborated with the composer on "Mrs. Santa Claus." "There's no way you can be a grump around him. When the network said yes to Mrs. Santa Claus,' he was singing and dancing and jumping around. I thought, if only I were young like Jerry and could experience things that immediately. I mean, he really is a Jerry Herman song. When faced with that kind of optimism, I hate it that my cynical heart is lifted. But it is." Taking Control, Moving On

Three years ago, Herman was behaving with far less exuberance. In fact, he was seriously questioning his place in the Broadway theater. He found New York oppressive and its winters brutalizing. And he was worried for his health. Then gossip columnist Cindy Adams took it upon herself, as Herman puts it, "to spill the beans" in the pages of the New York Post.

The item, which appeared on March 10, 1992, began innocently enough, with Adams reporting in her usual flibbertigibbet fashion that Jerry Herman was one busy man -- buying a house in California, opening a club in Dallas, flying to Czechoslovakia, even "going someplace in Virginia for something." The paragraph, however, ended with a whammy. "We just want Jerry, who's HIV-positive, to stay healthy," Adams wrote.

"Don't ask me how she knew," Herman says. "She never called me. But the fallout from that article would have made your head turn. Everybody in the world who cared about me -- and there are a lot who do -- got hysterical. People phoned in tears. Others who didn't know how to handle it stayed away. It changed my life.

"I certainly got fewer calls to work, and I understand that -- people thinking, Oh, we can't hire him, because he could get sick in the middle of a tryout.' I probably would have done another musical at that time, but everybody was scared. To this day, the gossip has never stopped that I am dying and, as you can see, that is hardly the case. Gossip doesn't go away, though."

Composer Michael Valenti, a longtime friend, dined with Herman the night the column broke. "It's not always easy to know when Jerry goes into a tailspin," he recalls. "He doesn't like to lay his pain and suffering on other people. He shows you his up side, because he truly believes that's what the world wants to see.

"But I could tell that Cindy Adams had almost broken his heart and spirit -- for that night, at least. Funny thing, though, all through the evening, he never said one word against her."

Herman still doesn't, other than to note that "I think she's a person who is more interested in getting an exciting headline than in what happens to the people she writes about." It is undeniable, however, that the episode sealed Herman's disenchantment with New York and fueled his desire to move west.

He hadn't had a Broadway hit since "La Cage" in 1983, and while it was a blockbuster, chalking up 1,791 performances, he was having trouble finding new material that stimulated him. Broadway's enthusiasm for the big, scenery-laden extravaganza, often British-born, seemed to exclude him. "I was growing stale," he confesses. "I was beginning to think I no longer wanted to be in the business of creating musicals just for Broadway. Basically, I hadn't been uproariously entertained by a new work in a decade. I hated the graffiti I found on my town house and the winos on the corner. I don't mean that cruelly. But I was living in one of the best parts of town and I was living in the middle of ugliness. I knew I needed a more peaceful and soothing environment."

Herman says it was "either very brave or very crazy of me to pick up and leave all that behind." But, in fact, he was obeying a fundamental impulse in all his musicals. Indeed, it's the force that, until recently, has motivated most American musicals: the urge to reach out, step up, take control, move on.

"I should have done it a long time ago," he says. "But the main thing is I am back as my old enthusiastic self again."

Which sounds suspiciously like something Dolly Levi tells the line of high-stepping waiters with the starched aprons, the white spats and the sparkle in their eyes. Keeping a Golden Age Alive

If Broadway had not made him a multi-millionaire, his real estate holdings probably would have. A graduate of the Parsons School of Design, Herman likes to "play" with houses -- remodeling them, inhabiting them for a while, then turning them over, usually for princely profits. His current residence, a Normandy-style mansion overlooking the 16th hole of the Bel Air Country Club, may be the most opulent yet. At 18,000 square feet, it is definitely the biggest.

Like most homes of L.A.'s rich and famous, it boasts a living room that could easily accommodate the casts of several musicals, a gym, a screening room, a pool out of a David Hockney painting, walk-in closets larger than some Manhattan boutiques, impeccably groomed gardens and automatic fortress gates. In one respect, however, it is unique. If you take the curved staircase to the basement -- the steps of which are carpeted in graduated tones of tan and beige -- you find yourself in a Jerry Herman museum.

In one corner, a mannequin sports the red gown in which Dolly Levi makes her celebrated entrance at the Harmonia Gardens. In another is a frilly, high-collared cape worn by one of the Cagelles, the gender-bending chorus line in "La Cage" consisting mostly of female impersonators. Beside it, a green street sign marks "Jerry Herman Way." (It was erected temporarily on 47th Street in New York, after "La Cage" passed its 1,500th performance.)

A large display case -- filled with ticket stubs, vintage photographs and the conductor's baton from "Mame" -- occupies the center of the room, while the walls are papered with posters of Herman's shows, Life magazine covers and Hirschfeld caricatures. The glittery memorabilia of a phenomenally successful career are all here. The exhibit is at once both a summing up and a showing off. Herman surveys it with the noblesse of the aristocrat in his wine cellar, but if you look closely, you can also see the pride of the Boy Scout displaying his merit badges. Some artists want to be admired. Herman wants to be loved.

He wonders if he should leave his collected papers to the Library of Congress or the Library for the Performing Arts at Lincoln Center. "They're both after me," he notes objectively. Still Tasting the High Life

While critics have never begrudged Herman his triumphs, he is widely held to be a throwback to an earlier, simpler time, when musicals were "musical comedies" and their hallmark was their high spirits. The intelligentsia's darling, on the other hand, is Stephen Sondheim, whose probing innovations have invariably overshadowed Herman's achievements. Sondheim, it is said, creates art, whereas Herman produces entertainment.

One of the rare times the two actually went head-to-head was for the 1984 Tony, when "La Cage" competed against "Sunday in the Park With George" for best musical. Herman won. But when he touted his victory as a vindication of "the simple, hummable show tune," he inadvertently contributed to the downplaying of his talent.

Even now he says, "Sondheim is a genius and I'm a songwriter. We're not in the same league as minds. I couldn't write about presidential assassins if you put a gun to my temple. My whole reason for being is to entertain people. I'm a mass audience person. That's where I aim, and that's where I hit."

Herman's populist appeal has always been his first, last and best line of defense -- rather like Liberace claiming that he cried all the way to the bank. "I know there will be productions of my shows playing 50 and 100 years from now," Herman asserts confidently. "They represent the happy period in the American musical theater. They really do. There will always be an audience that wants to laugh and see a parade of attractive men and women coming out on the stage, as they do in Put On Your Sunday Clothes.' And that's a good feeling. I'll be dead and buried, but somewhere a woman will still be walking down a staircase."

But there may be more to it than that.

Even as AIDS has spread its devastation, the disease has given new life to truths that, not so long ago, were considered tired or mawkish: We can only live for the present moment. Attitude is 90 percent of life. And yes, a joyful noise does lift the heart (and boost the immune system, it appears). In the age of AIDS, the optimist is taking the courageous, life-affirming stance, while the cynic is capitulating in advance. It requires a strong will to go on plugging happily; sad songs are as easy as whining.

Another lyric pops into Herman's head, this one from "Hello, Dolly!":

Before the parade passes by

I'm gonna go and taste Saturday's high life.

Before the parade passes by

I'm gonna get some life back into my life.

"I wrote that number for the character of Dolly Levi, who was brave enough to take one last chance in life," he says. "I liked that about her. I certainly didn't know I was writing about me at the time. But God knows, I was. Is that my theme song today?

"If I've been criticized, it's for being a Pollyanna. But I am that person. I was a happy positive thinker when I was 10, and I am at 62. . . . I've always appreciated the wonderful things that were happening to me as they were happening. I'm even more grateful for every day now."

His eyes fog up for the second time this morning, and the room is still. For a moment he looks small and lost behind that vast desk in his absurdly palatial office.

"When you're 28 years old and you feel well, the world is your plaything. You're not going to have problems with your parents. You're not going to have cancer. You're not going to have AIDS. You don't know that things like this can happen."

Now Jerry Herman knows. But the knowledge has only deepened his view of the world, not changed it. He was happy in the good times, and now he's happy through the bad -- he finds no particular wisdom in misery.

"Something has kept me from coming down with it," he says quietly of his many years free of AIDS-related illnesses. "I wish I could give you a profound explanation why -- I can't. Maybe some of us have the ability to clench a fist and carry on. But I'm not going to let this ruin the time I have. That's the big thing with me. I'm just not going to let fear ruin today and tomorrow."

Listen. It's all there in the songs. CAPTION: Jerry Herman on life with HIV: "It's not the end of the world. You can go on with a life." CAPTION: Jerry Herman with mementos from his upbeat musicals: "The fascinating thing is that this is the sort of stuff that has always come out of me."