JSON Jackson - 使用自定义序列化器序列化多态类时出现异常

使用自定义序列化器序列化多态类时，我们经常会遇到一些异常。这些异常可能是由于多态类的结构复杂性或序列化器的配置问题引起的。本文将介绍如何使用JSON Jackson库来处理这些异常，并提供一个案例代码来说明。

java
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
class Animal {
    protected String name;
    public Animal(String name) {
        this.name = name;
    }
}
class Dog extends Animal {
    private String breed;
    public Dog(String name, String breed) {
        super(name);
        this.breed = breed;
    }
}
class Cat extends Animal {
    private String color;
    public Cat(String name, String color) {
        super(name);
        this.color = color;
    }
}
public class PolymorphicSerializationExample {
    public static void main(String[] args) throws JsonProcessingException {
        Animal dog = new Dog("Buddy", "Labrador Retriever");
        Animal cat = new Cat("Whiskers", "Gray");
        ObjectMapper objectMapper = new ObjectMapper();
        SimpleModule module = new SimpleModule();
        module.addAbstractTypeMapping(Animal.class, Dog.class);
        module.addAbstractTypeMapping(Animal.class, Cat.class);
        objectMapper.registerModule(module);
        String dogJson = objectMapper.writeValueAsString(dog);
        String catJson = objectMapper.writeValueAsString(cat);
        System.out.println(dogJson);
        System.out.println(catJson);
    }
}