如何使用流lambda从对象集合的重复字段中获取聚合对象列表

import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

class Person {
    private String name;
    private int age;

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

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    @Override
    public String toString() {
        return "Person{name='" + name + "', age=" + age + "}";
    }
}

public class Main {
    public static void main(String[] args) {
        List<Person> people = Arrays.asList(
            new Person("Alice", 30),
            new Person("Bob", 25),
            new Person("Alice", 22),
            new Person("Bob", 28)
        );

        // 使用流API根据name字段分组，并计算每个分组的平均年龄
        Map<String, Double> averageAges = people.stream()
            .collect(Collectors.groupingBy(
                Person::getName,
                Collectors.averagingInt(Person::getAge)
            ));

        // 输出结果
        averageAges.forEach((name, avgAge) -> 
            System.out.println("Name: " + name + ", Average Age: " + avgAge)
        );
    }
}

Name: Alice, Average Age: 26.0
Name: Bob, Average Age: 26.5