String simpleMethodName(MethodDescriptor<?, ?> methodDescriptor) {
        final String simpleMethodName = simpleMethodNames.get(methodDescriptor);
        assert simpleMethodName != null : "No simple name found for " + methodDescriptor.getFullMethodName();
        return simpleMethodName;
    }
A registry of the implementation methods bound to a {@link GrpcService}. Used for method dispatch and
documentation generation.
grpc/src/main/java/com/linecorp/armeria/server/grpc/HandlerRegistry.java