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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());
            }
private static final String GRPC_ASYNC_RETURN_CLASS = "com.google.common.util.concurrent.ListenableFuture";
    private static final String TRI_ASYNC_RETURN_CLASS = "java.util.concurrent.CompletableFuture";
    private static final String REACTOR_RETURN_CLASS = "reactor.core.publisher.Mono";
    private static final String RX_RETURN_CLASS = "io.reactivex.Single";
    private static final String GRPC_STREAM_CLASS = "io.grpc.stub.StreamObserver";
    private static final Pack PB_PACK = o -> ((Message) o).toByteArray();
    private final Pack requestPack;
    private final Pack responsePack;
    private final UnPack requestUnpack;
    private final UnPack responseUnpack;
    public ReflectionPackableMethod(MethodDescriptor method, URL url, String serializeName) {
        Class<?>[] actualRequestTypes;
        Class<?> actualResponseType;
        switch (method.getRpcType()) {
            case CLIENT_STREAM:
            case BI_STREAM:
                actualRequestTypes = new Class<?>[]{
                    (Class<?>) ((ParameterizedType) method.getMethod()
                        .getGenericReturnType()).getActualTypeArguments()[0]};
                actualResponseType = (Class<?>) ((ParameterizedType) method.getMethod()
                    .getGenericParameterTypes()[0]).getActualTypeArguments()[0];
                break;
            case SERVER_STREAM:
                actualRequestTypes = method.getMethod().getParameterTypes();
                actualResponseType = (Class<?>) ((ParameterizedType) method.getMethod()
                    .getGenericParameterTypes()[1]).getActualTypeArguments()[0];
                break;
            case UNARY:
                actualRequestTypes = method.getParameterClasses();