dubbo内部参数类型的问题

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我想使用netty发起dubbo请求，如果我想调用的dubbo服务，方法的参数是数组或者容器类型以及自定义的类对象的时候，我设置dubbo的参数类型应该设置为什么呢？ String设置为 Ljava.lang.String，而自定义类设置为Lcom.xxx.xxx.xxx则无法发起调用是为什么呢？

Start by tracing how Dubbo encodes method parameter types for Netty requests, then compare the representations used for String, arrays, containers, and custom classes. The issue provides no file or test entry point; done would be a documented parameter representation that successfully invokes the described service.

Written by the indexing model from the issue text.