adding rsockets support into JDK

[Lu, Yingqi]

Hi Alan,

Thank you very much for the help on the javadoc changes. I will put them into new webrev.

I will modify the RDMA socket options following the example of standard socket options as well and submit version 8 for review today. 

Thank,
Lucy

Sent from my iPhone

> On Jun 25, 2018, at 4:51 AM, Alan Bateman <Alan.Bateman at oracle.com> wrote:
> 
>> On 23/06/2018 01:56, Lu, Yingqi wrote:
>> Hi All,
>> 
>> Here is the version 7 of the patch. http://cr.openjdk.java.net/~ylu/8195160.07/
>> 
>> In this version, I did:
>> 
>> 1. Added SO_LINGER supports (librdmacm supports it) to RDMA based sockets and socket channels. Tests are also updated with this newly added Socket Option.
>> 
>> 2. Added a private static variable rdmaOptionsSet to both java.net.Socket and java.net.ServerSocket. This way, I think the supportedOptions will return correct values between RDMA based sockets and regular sockets regardless of who is created first. Please let me know if I missed any cases here.
>> 
> I went over the API again. The factory methods don't have complete javadoc yet and I'm happy to help with that, see below.
> 
> The other part of the API is jdk.net.RdmaSocketOptions. The SQSIZE, RQSIZE and INLINE constants are currently public so they are leaking into the API. The API elements are RMDA_SQSIZE, RMDA_RQSIZE and RQSIZE_INLINE and these will need javadoc. Can you java.net.StandardSocketOption as an example of how the existing socket options are specified?
> 
> -Alan.
> 
> 
> A suggestion to add to the jdk.net.Sockets class description:
> 
>  * <p> The {@link #openRdmaSelector() openRdmaSelector}, {@link
>  * #openRdmaSocketChannel() openRdmaSocketChannel}, and {@link
>  * #openRdmaServerSocketChannel() openRdmaServerSocketChannel} methods
>  * create selectors and selectable channels for use with RDMA sockets.
>  * These objects are created a {@link java.nio.channels.spi.SelectorProvider
>  * SelectorProvider} that is not the default {@code SelectorProvider}.
>  * Consequently, selectable channels to RDMA sockets may not be multiplexed
>  * with selectable channel created by the default selector provider. The
>  * selector provider does not support datagram channels, its {@code
>  * openDatagramChannel} methods throw {@link UnsupportedOperationException}.
> 
> A suggestion for openRdmaSocketChannel:
> 
>     /**
>      * Opens a socket channel to a RDMA socket. A newly-created socket channel
>      * is {@link SocketChannel#isOpen() open}, not yet bound to a {@link
>      * SocketChannel#getLocalAddress() local address}, and not yet
>      * {@link SocketChannel#isConnected() connected}.
>      *
>      * <p> A socket channel to a RDMA socket supports all of the socket options
>      * specified by {@code SocketChannel}. In addition, it also supports the
>      * socket options specified by {@link RdmaSocketOptions}.
>      *
>      * @apiNote The rsocket implementation on Linux only supports IPv4 addresses.
>      * Consequently, attempting to bind or connect to an IPv6 address will fail
>      * with {@code UnsupportedAddressTypeException}.
>      *
>      * @throws IOException
>      *         If an I/O error occurs
>      * @throws UnsupportedOperationException
>      *         If RDMA sockets are not supported on this platform
>      *
>      * @since N
>      */
> 
> A suggestion for openRdmaServerSocketChannel:
> 
>     /**
>      * Opens a server-socket channel to a RDMA socket. A newly-created socket
>      * channel is {@link SocketChannel#isOpen() open} but not yet bound to a
>      * {@link SocketChannel#getLocalAddress() local address}.
>      *
>      * @apiNote The rsocket implementation on Linux only supports IPv4 addresses.
>      * Consequently, attempting to bind to an IPv6 address will fail with
>      * {@code UnsupportedAddressTypeException}.
>      *
>      * @throws IOException
>      *         If an I/O error occurs
>      * @throws UnsupportedOperationException
>      *         If RDMA sockets are not supported on this platform
>      *
>      * @since N
>      */
> 
> A suggestion for openRdmaSelector:
> 
>     /**
>      * Opens a selector to multiplex selectable channels to RDMA sockets.
>      *
>      * @throws IOException
>      *         If an I/O error occurs
>      * @throws UnsupportedOperationException
>      *         If RDMA sockets are not supported on this platform
>      *
>      * @since N
>      */
> 
> A suggestion for openRdmaSocket:
> 
>     /**
>      * Creates an unconnected RDMA socket.
>      *
>      * <p> A RDMA socket supports the same socket options that that {@code
>      * java.net.Socket} defines. In addition, it also supports the socket options
>      * specified by {@link RdmaSocketOptions}.
>      *
>      * @apiNote The rsocket implementation on Linux only supports IPv4 addresses.
>      * Consequently, attempting to bind or connect to an IPv6 address will fail
>      * with {@code IllegalArgumentException}.
>      *
>      * @throws IOException
>      *         If an I/O error occurs
>      * @throws UnsupportedOperationException
>      *         If RDMA sockets are not supported on this platform
>      *
>      * @since N
>      */
> 
> A suggestion for openRdmaServerSocket:
> 
>     /**
>      * Creates an unbound RDMA server socket.
>      *
>      * <p> A RDMA socket supports the same socket options that that {@code
>      * java.net.ServerSocket} defines.
>      *
>      * @apiNote The rsocket implementation on Linux only supports IPv4 addresses.
>      * Consequently, attempting to bind to an IPv6 address will fail with
>      * {@code IllegalArgumentException}.
>      *
>      * @throws IOException
>      *         If an I/O error occurs
>      * @throws UnsupportedOperationException
>      *         If RDMA sockets are not supported on this platform
>      *
>      * @since N
>      */