GSON序列化具有存储在不同对象中的类型的多态性对象

import com.google.gson.TypeAdapter;
import com.google.gson.stream.JsonReader;
import com.google.gson.stream.JsonWriter;

import java.io.IOException;

public class PolymorphicObjectAdapter extends TypeAdapter<PolymorphicObject> {

    @Override
    public void write(JsonWriter out, PolymorphicObject obj) throws IOException {
        out.beginObject();
        out.name("type").value(obj.getClass().getName()); // 存储对象的类型信息
        out.name("data").value(obj.getData()); // 存储对象的数据
        out.endObject();
    }

    @Override
    public PolymorphicObject read(JsonReader in) throws IOException {
        in.beginObject();
        String type = null;
        String data = null;
        while (in.hasNext()) {
            String name = in.nextName();
            if (name.equals("type")) {
                type = in.nextString(); // 读取对象的类型信息
            } else if (name.equals("data")) {
                data = in.nextString(); // 读取对象的数据
            }
        }
        in.endObject();

        // 根据类型信息创建正确的对象类型
        PolymorphicObject obj = null;
        if (type != null && data != null) {
            if (type.equals(ConcreteObject1.class.getName())) {
                obj = new ConcreteObject1(data);
            } else if (type.equals(ConcreteObject2.class.getName())) {
                obj = new ConcreteObject2(data);
            }
        }
        return obj;
    }
}

Gson gson = new GsonBuilder()
        .registerTypeAdapter(PolymorphicObject.class, new PolymorphicObjectAdapter())
        .create();

// 序列化对象
String json = gson.toJson(polymorphicObject);

// 反序列化对象
PolymorphicObject obj = gson.fromJson(json, PolymorphicObject.class);