Jackson：在序列化嵌套POJO时动态切换序列化器

import java.util.UUID;

public class Request1 {
    private UUID id;
    private MyPojo pojo;

    // Getters and setters...
}

public class Request2 {
    private UUID id;

    @JsonSerialize(using = MyPojoSerializer.class)
    private MyPojo pojo;

    // Getters and setters...
}

public class MyPojo {
    private Foo foo;
    private Bar bar;

    public Foo getFoo() {
        return foo;
    }

    public Bar getBar() {
        return bar;
    }

    public static class Bar {
        private Foo other;

        public Foo getOther() {
            return other;
        }
    }
}

public class Foo {
    private String value1;
    private String value2;

    public String getValue1() {
        return value1;
    }

    public String getValue2() {
        return value2;
    }
}

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import java.io.IOException;

public class MyPojoSerializer extends JsonSerializer<MyPojo> {

    @Override
    public void serialize(final MyPojo value, final JsonGenerator gen,
            final SerializerProvider provider) throws IOException {
        gen.writeStartObject();
        // 使用默认序列化器序列化 bar 字段
        gen.writeFieldName("bar");
        provider.defaultSerializeField("bar", value.getBar(), gen);

        // 手动序列化 foo 字段，使用自定义的序列化方法
        gen.writeFieldName("foo");
        serializeFoo(value.getFoo(), gen);
        gen.writeEndObject();
    }

    private void serializeFoo(final Foo value, final JsonGenerator gen) throws IOException {
        gen.writeStartArray();
        gen.writeString(value.getValue1());
        gen.writeString(value.getValue2());
        gen.writeEndArray();
    }
}