java - jsonrpc4j:如何将类型信息添加到参数？

我正在使用jsonrpc4j并被卡住。我举了一个小例子来说明我的问题:

抽象类:

@JsonTypeInfo(use = JsonTypeInfo.Id.NAME)
@JsonSubTypes(value = { @JsonSubTypes.Type(value = Walnut.class) })
public abstract class Nut {

}

具体子类:

public class Walnut extends Nut {

}

服务接口:

public interface ServiceInterface {
    public Nut getNut();
    public void setNut(Nut nut);
}

服务本身:

public class Service implements ServiceInterface {
    public Nut getNut() { return new Walnut(); }
    public void setNut(Nut nut) {}
}

服务器:

JsonRpcServer rpcServer = new JsonRpcServer(new ObjectMapper(), new Service());
StreamServer streamServer = new StreamServer(rpcServer, 50, 1420,
        50, InetAddress.getByName("127.0.0.1"));
streamServer.start();

客户:

JsonRpcClient jsonRpcClient = new JsonRpcClient(new ObjectMapper());
ServiceInterface remoteService = ProxyUtil.createClientProxy(
        ServiceInterface.class.getClassLoader(),
        ServiceInterface.class, jsonRpcClient,
        new Socket(InetAddress.getByName("127.0.0.1"), 1420));

如果我调用remoteService.getNut()一切都按预期工作，则日志显示:

JSON-PRC Request: {"id":"6064348714687420633","jsonrpc":"2.0","method":"getNut"}
JSON-PRC Response: {"jsonrpc":"2.0","id":"6064348714687420633",
        "result":{"@type":"Walnut"}}

如果我调用remoteService.setNut(new Walnut())，服务器将引发异常，日志将输出:

JSON-PRC Request {"id":"9194853851254039397","jsonrpc":"2.0",
        "method":"setNut","params":[{}]}
Error in JSON-RPC Service com.fasterxml.jackson.databind.JsonMappingException:
        Unexpected token (END_OBJECT), expected FIELD_NAME:
        missing property '@type' that is to contain type id  (for class Nut)

缺少参数的类型信息，因为代理将所有参数都包装到一个对象数组中(请参阅我的最后一个question，以了解在这种情况下为什么缺少信息类型)。

如何实现所需的序列化？我试图启用默认键入并通过混合来注释(使用@JsonTypeInfo)Object.class，但是两者都失败了(以下例外)。

启用默认键入[remoteService.getNut()，服务器端错误]:

Exception while handling request
        com.fasterxml.jackson.databind.JsonMappingException:
        Unexpected token (START_OBJECT), expected START_ARRAY:
        need JSON Array to contain As.WRAPPER_ARRAY type information for
        class com.fasterxml.jackson.databind.JsonNode

启用默认键入[remoteService.setNut(new Walnut())，客户端错误]:

Exception in thread "main" java.lang.IllegalArgumentException:
        Unexpected token (START_ARRAY), expected VALUE_STRING:
        need JSON String that contains type id (for subtype of
        com.fasterxml.jackson.databind.JsonNode)

使用混入[remoteService.getNut()，服务器端错误]:

Exception while handling request
        java.lang.IllegalArgumentException:
        Could not resolve type id 'DefaultErrorResolver$ErrorData'
        into a subtype of
        [simple type, class com.fasterxml.jackson.databind.JsonNode]

与混入[remoteService.setNut(new Walnut())，客户端错误]:

Exception in thread "main" java.lang.ClassCastException:
        [Ljava.lang.Object; cannot be cast to
        com.fasterxml.jackson.databind.JsonNode

有任何想法吗？

最佳答案

我通过修补库解决了我的问题。现在，它一个接一个地序列化所有参数，然后将它们连接起来。错误报告和补丁可在http://code.google.com/p/jsonrpc4j/issues/detail?id=49中找到。