public class XmlObject
{
    public string Body { get; set; }
}

public class JsonObject
{
    public string Head { get; set; }
    public string Token { get; set; }
}

public class XmlController
{
    public JsonAdapter _jsonAdapter = new JsonAdapter();

    public void Process(XmlObject obj)
    {
        obj.Body = "test test";
    }

    public void ProcessJson(JsonObject obj)
    {
        var xml = _jsonAdapter.ConvertJsonToXml(obj);

        Process(xml);
    }

}

public class JsonAdapter
{
    public XmlObject ConvertJsonToXml(JsonObject obj)
    {
        XmlObject result = new XmlObject();
        result.Body = obj.Token;
        return result;
    }
}