adding rsockets support into JDK

[Alan Bateman]

On 01/07/2018 04:01, Lu, Yingqi wrote:
> Hi All,
>
> Here is the webrev.08 of the patch http://cr.openjdk.java.net/~ylu/8195160.08/
>
> In this version,
>
> 1. Added Javadoc for 5 newly introduced APIs inside jdk.net.Sockets. Thanks to Alan for his help!
>
> 2. Changed RQSIZE, SQSIZE and INLINE constants from public and private; Added comments for RDMA_SQSIZE, RDMA_RQSIZE and RDMA_INLINE options.
>
> 3. Currently, the patch compiles on Linux, Windows and MacOS.
>
I did another pass over the API changes.

In SocketImpl, the setSocket and setServerSocket methods are changed to 
protected so this means this will be part of the SocketImpl API. Is this 
needed? (I'm just wondering if we can avoid this API change).

The API addition to ServerSocket is okay, we'll just need to add the 
@since when it gets targeted.

Thanks for including the javadoc for the methods added to 
jdk.net.Sockets, I think that looks good now (just one place where it 
has @since N).

For RdmaSocketOptions then one suggestion is to look at 
java.net.StandardSocketOptions or jdk.net.ExtendedSocketOptions to see 
the style used for the other socket options. I think the main thing that 
is missing is text to give some idea of the values allowed and some idea 
on when the socket option can be set (before the socket it bound, after 
it is bound, only when connected).

One comment on the implementation for now is that I see 
supportedOptions() is checking if the impl is the RDMA impl. I assume 
this isn't needed as it delegates to the impl. My point is that I don't 
think Socket and ServerSocket should have code checking if the impl 
class is "rdma.ch.RdmaSocketImpl".

I will go through the implementation and tests in more detail once I can 
find time.

-Alan