如何从flatMap创建HashMap？

import java.util.AbstractMap;
import java.util.HashMap;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class FlatMapToHashMapExample {
    public static void main(String[] args) {
        // 假设我们有一个包含Person对象的流
        Stream<Person> personStream = Stream.of(
                new Person(1, "Alice"),
                new Person(2, "Bob"),
                new Person(3, "Charlie")
        );

        // 使用flatMap将Person对象转换为键值对流，并将其收集到HashMap中
        Map<Integer, String> hashMap = personStream.flatMap(person -> Stream.of(new AbstractMap.SimpleEntry<>(person.getId(), person.getName())))
                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));

        // 打印HashMap
        System.out.println(hashMap);
    }
}

class Person {
    private int id;
    private String name;

    public Person(int id, String name) {
        this.id = id;
        this.name = name;
    }

    public int getId() {
        return id;
    }

    public String getName() {
        return name;
    }
}