A 35-year-old California law school graduate -- who had been charged with aggravated harassment and criminal trespass in pursuit of Caroline Kennedy -- was tried today and found guilty.

But by the time the conviction came in Manhattan Criminal Court, the defendant, Kevin King, had in a peculiar way realized at least part of his fantasy. He had the opportunity not only to meet the woman with whom he had become romantically obsessed, but also to cross-examine her on the witness stand in a bizarre courtroom drama in which he had insisted he defend himself.

In a situation eerily reminiscent of John W. Hinckley's pursuit of actress Jodie Foster, King, reportedly of a wealthy Palo Alto, Calif., family, had tried to meet Kennedy, seeking her out in her job at the Metropolitan Museum of Art, and spending the night in the halls of her apartment building harassing her roommate.

Like Hinckley, President Reagan's alleged assailant, King sent Kennedy love letters, in some of which he referred to "forces outside himself." Like Hinckley, although he had never met the woman with whom he was obsessed, he said he intended to marry her.

"I came to New York on a mission of love," he said in Manhattan Criminal Court.

But in this highly unusual case -- in which the defendant dismissed the attorney his parents had reportedly hired to defend him -- King had an opportunity Hinckley never had: not simply to see the woman he had flown across the country to ask to marry him but, as his own attorney, compel her to conversation.

That highly charged moment, the hunter confronting his prey, was a moment that clearly dazzled King.

The blond, blue-eyed defendant, dressed in a wrinkled blue prison shirt, trousers and sneakers, had appeared out of his depth all day during courtroom proceedings. Making his opening remarks to the court, he found it necessary to ask the judge where to stand. As Kennedy's name was called, early in the afternoon, he became at once the rattled, embarrassed suitor. He giggled nervously, broke into laughter, interrupted his questions mid-sentence to begin anew. At times, he simply stared.

Kennedy, dressed in a purple turtleneck and plaid skirt, looked like the newly graduated working girl that she is. She seemed, in a quiet way, appalled, and studiously avoided looking at King.

Under direct examination by assistant district attorney Alan Buonpastore, she told the court how King had interrupted her while she was eating lunch at the museum; how she had found him, that evening, in front of her building and become so frightened she had gone to her mother's home. She also told the district attorney of her fears after receiving the letters.

"I was rather frightened . . . they didn't seem to make much sense . . . there were some obscenities in the cards . . . knowing some of the things that have happened in the past, I was a little nervous," she told the district attorney.

Cross-examination by the man who had sent her the cards seemed an ordeal.

"Do you recall looking at me, your face looked different . . ." he said at one point in a rambling, disjointed manner.

"I tried not to look at you," she said, staring at the floor, trying to avoid him even as she spoke. "You were staring at me without blinking, I just kept trying to keep my head . . ."

King spoke of the letters, two of which he had written from prison after his arrest. One of those letters, the courtroom later learned, contained a proposal: "Why don't you marry me -- we can borrow some rice from your mother's wedding." Another was obscene. "Next time I'll f--- all your relatives unless you marry me," he wrote.

"You mentioned profanity," King said to Kennedy in his cross-examination. "Did you take it seriously as to constitute a scare?"

"Yes," said the woman whose father and uncle were killed by assassins, saying it shortly and grimly, still staring at the floor.

"Wouldn't you say the card was humorous in some respects?" the man pursued

"No," said Kennedy.

The son of a family of lawyers, King is a graduate of the Hastings Law School in San Francisco, according to Manhattan district attorney spokeswoman Mary deBourbon. Whether he had been admitted to the bar is unknown, though King had worked as a law researcher in his father's office, according to deBourbon. Arrested Aug. 20, he had been remanded to Bellevue hospital here for psychiatric examination, and was found fit to stand trial. The lawyer retained by the King family, Albert Felix, said that he been removed from the case by King, who insisted on defending himself and who also waived his rights to a jury trial. Felix also confirmed that while King had been offered a plea by the district attorney's office -- adjournment in contemplation of dismissal, a plea which in effect puts a defendant on immediate parole -- that was also rejected by King.

Some reports have it that he rejected that offer because he wanted to meet and speak with Kennedy -- a report that King, under direct examination by assistant district attorney Buonpastore, seemed to confirm on the stand.

"Didn't you get arrested to meet Caroline Kennedy here in court?" asked the district atttorney.

"Yeah, that's true," said King, adding, "it was kind of a last resort."

At times, King outlined his defense strategy by numbering his questions and thinking out loud.

"I'll switch here to Miranda warning," he said.

He accused all the witnesses of being "liars," and said that Kennedy, whom he insisted he had met several times in San Francisco, was a "liar." He refused to accept her contention on the witness stand that she had never been in San Francisco in her life.

"Have you ever sent a friend or third party to California to impersonate so that I would be misled?" he asked. "In '65, '75, and '80?"

On the stand, Kennedy was required to respond.

"No," she said.

"I withdraw my offer of marriage," said King, tittering to himself, and adding, "that's all the questions I have."

There was no humor, however, from the witnesses -- the well-dressed and well-spoken tenants of Caroline Kennedy's apartment house who testified that King had talked his way into the building by pretending to be a friend of Kennedy's, and who told how King returned to the building time and again despite requests by both tenants and police that he leave. Kennedy shares her apartment, according to the Associated Press, with a girlfriend and a male roommate, Andrew Karsch, a film producer.

In his defense, King questioned Karsch, who had earlier testified that King had called him nine times in one day alone, even after being told that he had become an annoyance. King, in his cross-examination, attempted to prove that he had not trespassed in the building or made a nuisance of himself.

"Did I never leave when you told me to?"

"No," said Karsch. "You would look me in the eye very earnestly, assure me you would, then reappear repeatedly."

Kennedy was grim in her 30 minutes on the stand. Staring at the floor or directly in front of her, she told of her first meeting with King on Aug. 18, in her job at the museum.

"I had my lunch and I was on my way to eat outside in the staff cafeteria, and as I was walking I heard somebody say, 'That's her -- there she goes' . . . Someone came up to me and said, 'Are you Caroline Kennedy?' I said, 'Yes.' He said, 'I'm Kevin King and I think we met before in San Francisco.' I said, 'I've never been in San Francisco.' He said he felt very strongly that we'd met."

Kennedy testified that it was difficult to get rid of him.

"I said, 'Listen, I don't know you and one of us is going to leave now.' "

She said that King left, but returned to the museum later that day. She also said that, since she had seen King carrying a map with her address written on it, "I was afraid he might come and find me -- I went to my mother's house." She also testified that the following day, in a cab, she saw King in front of her house again. "I went by my house and I saw the defendant on the doorstep and it frightened me . . ." she said.

She also said she was frightened after receiving two letters from King even after his arrest.

In one he said: "I've not backed off from my purpose before my arrest to play an active part in your life."

Criminal Court Judge John Bradley, who found King guilty, set sentencing for next Friday. King, who did not respond as the judgment came, faces a maximum penalty of a year in jail and $1,000 fine. He was returned to Rikers Island jail in lieu of $25,000 bail.