使用java 8从列表中获取子类的第一个实例。

class Animal {
    private String name;

    public Animal(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }
}

class Dog extends Animal {
    public Dog(String name) {
        super(name);
    }
}

import java.util.Arrays;
import java.util.List;
import java.util.Optional;

public class Main {
    public static void main(String[] args) {
        List<Animal> animals = Arrays.asList(
            new Animal("Cat"),
            new Dog("Buddy"),
            new Animal("Bird"),
            new Dog("Max")
        );

        Optional<Dog> firstDog = animals.stream()
            .filter(animal -> animal instanceof Dog)
            .map(animal -> (Dog) animal)
            .findFirst();

        firstDog.ifPresent(dog -> System.out.println("First dog found: " + dog.getName()));
    }
}

firstDog.ifPresent(dog -> System.out.println("First dog found: " + dog.getName()));