/*

 * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.net;

import java.net.ProtocolFamily;

import java.net.ServerSocket;

import java.net.Socket;

import java.net.StandardProtocolFamily;

import java.nio.channels.Selector;

import java.nio.channels.ServerSocketChannel;

import java.nio.channels.SocketChannel;

import java.nio.channels.spi.SelectorProvider;

import java.io.IOException;

import java.util.Objects;

import jdk.internal.net.rdma.RdmaPollSelectorProvider;

import jdk.internal.net.rdma.RdmaSocketProvider;

/**

 * This class defines static factory methods to create sockets and channels to

 * RDMA-based sockets, and selectors to multiplex channels to RDMA sockets.

 *

 * <p> The {@linkplain #openSocket(ProtocolFamily) openSocket} and {@linkplain

 * #openServerSocket(ProtocolFamily) openServerSocket} methods create RDMA-based

 * TCP sockets.

 *

 * <p> The {@linkplain #openSocketChannel(ProtocolFamily) openSocketChannel} and

 * {@linkplain #openServerSocketChannel(ProtocolFamily) openServerSocketChannel}

 * methods open {@link java.nio.channels.SelectableChannel selectable channels}

 * {@linkplain Selector} for multiplexing selectable channels to RDMA sockets.

 * channels opened by the default system-wide {@link SelectorProvider selector

 * provider}. Furthermore, the RDMA selector provider does not support datagram

 * channels or pipes; its {@linkplain SelectorProvider#openDatagramChannel

 * methods throw {@code UnsupportedOperationException}.

 *

 * <p> Unless otherwise noted, passing a {@code null} argument will cause a

 * {@linkplain NullPointerException} to be thrown.

 *

 * @implNote The RDMA selector provider supports channels to both IPv4 and

 * IPv6 RDMA sockets. If the no-arg {@linkplain SelectorProvider#openSocketChannel()

 * openSocketChannel} or {@linkplain SelectorProvider#openServerSocketChannel()

 *

 * @since 13

 */

public class RdmaSockets {

    private RdmaSockets() {}

    /**

     * Creates an unbound and unconnected RDMA socket.

     *

     * <p> An RDMA socket supports the socket options

     * {@link java.net.StandardSocketOptions#SO_RCVBUF SO_RCVBUF},

     * {@link java.net.StandardSocketOptions#SO_REUSEADDR SO_REUSEADDR},

     * {@link java.net.StandardSocketOptions#SO_SNDBUF SO_SNDBUF},

     * {@link java.net.StandardSocketOptions#TCP_NODELAY TCP_NODELAY},

     * and those specified by {@link RdmaSocketOptions}.

     *

     * <p> When {@link Socket#bind binding} the socket to a local address, or

     * {@link Socket#connect connecting} the socket, the socket address specified

     * to the {@code bind} and {@code connect} methods must correspond to the

     * protocol family specified here.

     *

     * @param  family

     *         The protocol family

     *

     * @throws IOException

     *         If an I/O error occurs

     * @throws UnsupportedOperationException

     *         If RDMA sockets are not supported on this platform or if the

     *         specified protocol family is not supported. For example, if

     *         the parameter is {@link java.net.StandardProtocolFamily#INET6

     *         StandardProtocolFamily.INET6} but IPv6 is not enabled on the

     *         platform.

     */

    public static Socket openSocket(ProtocolFamily family) throws IOException {

        Objects.requireNonNull(family, "protocol family is null");

        return RdmaSocketProvider.openSocket(family);

    }

    /**

     * Creates an unbound RDMA server socket.

     *

     * <p> An RDMA server socket supports the socket options

     * {@link java.net.StandardSocketOptions#SO_RCVBUF SO_RCVBUF},

     * {@link java.net.StandardSocketOptions#SO_REUSEADDR SO_REUSEADDR},

     * and those specified by {@link RdmaSocketOptions}.

     *

     * <p> When binding the socket to an address, the socket address specified

     * to the {@linkplain ServerSocket#bind bind} method must correspond to the

     * protocol family specified here.

     *

     * @param family

     *        The protocol family

     *

     * @throws IOException

     *         If an I/O error occurs

     * @throws UnsupportedOperationException

     *         If RDMA sockets are not supported on this platform or if the

     *         specified protocol family is not supported. For example, if

     *         the parameter is {@link java.net.StandardProtocolFamily#INET6

     *         StandardProtocolFamily.INET6} but IPv6 is not enabled on the

     *         platform.

     */

    public static ServerSocket

    openServerSocket(ProtocolFamily family) throws IOException {

        Objects.requireNonNull(family, "protocol family is null");

        return RdmaSocketProvider.openServerSocket(family);

    }

    /**

     * Opens a socket channel to an RDMA socket. A newly created socket channel

     * is {@link java.nio.channels.Channel#isOpen() open} but not yet {@link

     * SocketChannel#bind bound} or {@link SocketChannel#isConnected() connected}.

     *

     * <p> A socket channel to an RDMA socket supports the socket options

     * {@link java.net.StandardSocketOptions#SO_RCVBUF SO_RCVBUF},

     * {@link java.net.StandardSocketOptions#SO_REUSEADDR SO_REUSEADDR},

     * {@link java.net.StandardSocketOptions#SO_SNDBUF SO_SNDBUF},

     * {@link java.net.StandardSocketOptions#TCP_NODELAY TCP_NODELAY},

     * and those specified by {@link RdmaSocketOptions}.

     *

     * <p> When binding the channel's socket to a local address, or {@link

     * SocketChannel#connect connecting} the channel's socket, the socket address

     * specified to the {@code bind} and {@code connect} methods must correspond

     * to the protocol family specified here.

     *

     * @param  family

     *         The protocol family

     *

     * @throws IOException

     *         If an I/O error occurs

     * @throws UnsupportedOperationException

     *         If RDMA sockets are not supported on this platform or if the

     *         specified protocol family is not supported. For example, if

     *         the parameter is {@link java.net.StandardProtocolFamily#INET6

     *         StandardProtocolFamily.INET6} but IPv6 is not enabled on the

     *         platform.

     */

    public static SocketChannel

    openSocketChannel(ProtocolFamily family) throws IOException {

        Objects.requireNonNull(family, "protocol family is null");

        return RdmaPollSelectorProvider.provider().openSocketChannel(family);

    }

    /**

     * Opens a server-socket channel to an RDMA socket. A newly created

     * server-socket is {@link java.nio.channels.Channel#isOpen() open} but not

     * yet {@link ServerSocketChannel#bind bound}.

     *

     * <p> A server-socket channel to an RDMA server socket supports the socket

     * options {@link java.net.StandardSocketOptions#SO_RCVBUF SO_RCVBUF},

     * {@link java.net.StandardSocketOptions#SO_REUSEADDR SO_REUSEADDR},

     * and those specified by {@link RdmaSocketOptions}.

     *

     * <p> When binding the channel's socket to a local address, the address

     * specified to the {@linkplain ServerSocketChannel#bind bind} method must

     * correspond to the protocol family specified here.

     *

     * @param  family

     *         The protocol family

     *

     * @throws IOException

     *         If an I/O error occurs

     * @throws UnsupportedOperationException

     *         If RDMA sockets are not supported on this platform or the

     *         specified protocol family is not supported. For example, if

     *         the parameter is {@link java.net.StandardProtocolFamily#INET6

     *         StandardProtocolFamily.INET6} but IPv6 is not enabled on the

     *         platform.

     */

    public static ServerSocketChannel

    openServerSocketChannel(ProtocolFamily family) throws IOException {

        Objects.requireNonNull(family, "protocol family is null");

        return RdmaPollSelectorProvider.provider().openServerSocketChannel(family);

    }

    /**

     * 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

     */

    public static Selector openSelector() throws IOException {

        return RdmaPollSelectorProvider.provider().openSelector();

    }

}