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![image](https://user-images.githubusercontent.com/15622677/221121735-39571dc2-d771-493a-9d3c-14f8a8ee239f.png)
ReflectionPackableMethod类中 argument.getClass().getName()报空指针
            for (Object argument : arguments) {
                builder.addArgTypes(argument.getClass().getName());
                ByteArrayOutputStream bos = new ByteArrayOutputStream();
                multipleSerialization.serialize(url, serialize, argument.getClass(), argument, bos);
                builder.addArgs(bos.toByteArray());
            }
}
        
        if (streamParameterCount == 1) {
            if (javaParameterCount + protobufParameterCount > 1) {
                throw new IllegalStateException(
                    "method params error: server stream does not support more than one normal param."
                        + " method=" + methodName);
            }
            
            if (!secondParameterStream) {
                throw new IllegalStateException(
                    "method params error: server stream's second param must be StreamObserver."
                        + " method=" + methodName);
            }
        }
        if (methodDescriptor.getRpcType() != MethodDescriptor.RpcType.UNARY) {
            if (MethodDescriptor.RpcType.SERVER_STREAM == methodDescriptor.getRpcType()) {
                if (!secondParameterStream) {
                    throw new IllegalStateException(
                        "method params error:server stream's second param must be StreamObserver."
                            + " method=" + methodName);
                }
            }
            
            if (returnClassProtobuf) {
                if (javaParameterCount > 0) {
                    throw new IllegalStateException(
                        "method params error: both normal and protobuf param found. method="
                            + methodName);
                }