| /* |
| * Copyright (c) 2007, 2013, 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 java.nio.channels; |
| |
| import java.nio.channels.spi.*; |
| import java.net.SocketOption; |
| import java.net.SocketAddress; |
| import java.util.concurrent.Future; |
| import java.io.IOException; |
| |
| /** |
| * An asynchronous channel for stream-oriented listening sockets. |
| * |
| * <p> An asynchronous server-socket channel is created by invoking the |
| * {@link #open open} method of this class. |
| * A newly-created asynchronous server-socket channel is open but not yet bound. |
| * It can be bound to a local address and configured to listen for connections |
| * by invoking the {@link #bind(SocketAddress,int) bind} method. Once bound, |
| * the {@link #accept(Object,CompletionHandler) accept} method |
| * is used to initiate the accepting of connections to the channel's socket. |
| * An attempt to invoke the <tt>accept</tt> method on an unbound channel will |
| * cause a {@link NotYetBoundException} to be thrown. |
| * |
| * <p> Channels of this type are safe for use by multiple concurrent threads |
| * though at most one accept operation can be outstanding at any time. |
| * If a thread initiates an accept operation before a previous accept operation |
| * has completed then an {@link AcceptPendingException} will be thrown. |
| * |
| * <p> Socket options are configured using the {@link #setOption(SocketOption,Object) |
| * setOption} method. Channels of this type support the following options: |
| * <blockquote> |
| * <table border summary="Socket options"> |
| * <tr> |
| * <th>Option Name</th> |
| * <th>Description</th> |
| * </tr> |
| * <tr> |
| * <td> {@link java.net.StandardSocketOptions#SO_RCVBUF SO_RCVBUF} </td> |
| * <td> The size of the socket receive buffer </td> |
| * </tr> |
| * <tr> |
| * <td> {@link java.net.StandardSocketOptions#SO_REUSEADDR SO_REUSEADDR} </td> |
| * <td> Re-use address </td> |
| * </tr> |
| * </table> |
| * </blockquote> |
| * Additional (implementation specific) options may also be supported. |
| * |
| * <p> <b>Usage Example:</b> |
| * <pre> |
| * final AsynchronousServerSocketChannel listener = |
| * AsynchronousServerSocketChannel.open().bind(new InetSocketAddress(5000)); |
| * |
| * listener.accept(null, new CompletionHandler<AsynchronousSocketChannel,Void>() { |
| * public void completed(AsynchronousSocketChannel ch, Void att) { |
| * // accept the next connection |
| * listener.accept(null, this); |
| * |
| * // handle this connection |
| * handle(ch); |
| * } |
| * public void failed(Throwable exc, Void att) { |
| * ... |
| * } |
| * }); |
| * </pre> |
| * |
| * @since 1.7 |
| */ |
| |
| public abstract class AsynchronousServerSocketChannel |
| implements AsynchronousChannel, NetworkChannel |
| { |
| private final AsynchronousChannelProvider provider; |
| |
| /** |
| * Initializes a new instance of this class. |
| * |
| * @param provider |
| * The provider that created this channel |
| */ |
| protected AsynchronousServerSocketChannel(AsynchronousChannelProvider provider) { |
| this.provider = provider; |
| } |
| |
| /** |
| * Returns the provider that created this channel. |
| * |
| * @return The provider that created this channel |
| */ |
| public final AsynchronousChannelProvider provider() { |
| return provider; |
| } |
| |
| /** |
| * Opens an asynchronous server-socket channel. |
| * |
| * <p> The new channel is created by invoking the {@link |
| * java.nio.channels.spi.AsynchronousChannelProvider#openAsynchronousServerSocketChannel |
| * openAsynchronousServerSocketChannel} method on the {@link |
| * java.nio.channels.spi.AsynchronousChannelProvider} object that created |
| * the given group. If the group parameter is <tt>null</tt> then the |
| * resulting channel is created by the system-wide default provider, and |
| * bound to the <em>default group</em>. |
| * |
| * @param group |
| * The group to which the newly constructed channel should be bound, |
| * or <tt>null</tt> for the default group |
| * |
| * @return A new asynchronous server socket channel |
| * |
| * @throws ShutdownChannelGroupException |
| * If the channel group is shutdown |
| * @throws IOException |
| * If an I/O error occurs |
| */ |
| public static AsynchronousServerSocketChannel open(AsynchronousChannelGroup group) |
| throws IOException |
| { |
| AsynchronousChannelProvider provider = (group == null) ? |
| AsynchronousChannelProvider.provider() : group.provider(); |
| return provider.openAsynchronousServerSocketChannel(group); |
| } |
| |
| /** |
| * Opens an asynchronous server-socket channel. |
| * |
| * <p> This method returns an asynchronous server socket channel that is |
| * bound to the <em>default group</em>. This method is equivalent to evaluating |
| * the expression: |
| * <blockquote><pre> |
| * open((AsynchronousChannelGroup)null); |
| * </pre></blockquote> |
| * |
| * @return A new asynchronous server socket channel |
| * |
| * @throws IOException |
| * If an I/O error occurs |
| */ |
| public static AsynchronousServerSocketChannel open() |
| throws IOException |
| { |
| return open(null); |
| } |
| |
| /** |
| * Binds the channel's socket to a local address and configures the socket to |
| * listen for connections. |
| * |
| * <p> An invocation of this method is equivalent to the following: |
| * <blockquote><pre> |
| * bind(local, 0); |
| * </pre></blockquote> |
| * |
| * @param local |
| * The local address to bind the socket, or <tt>null</tt> to bind |
| * to an automatically assigned socket address |
| * |
| * @return This channel |
| * |
| * @throws AlreadyBoundException {@inheritDoc} |
| * @throws UnsupportedAddressTypeException {@inheritDoc} |
| * @throws SecurityException {@inheritDoc} |
| * @throws ClosedChannelException {@inheritDoc} |
| * @throws IOException {@inheritDoc} |
| */ |
| public final AsynchronousServerSocketChannel bind(SocketAddress local) |
| throws IOException |
| { |
| return bind(local, 0); |
| } |
| |
| /** |
| * Binds the channel's socket to a local address and configures the socket to |
| * listen for connections. |
| * |
| * <p> This method is used to establish an association between the socket and |
| * a local address. Once an association is established then the socket remains |
| * bound until the associated channel is closed. |
| * |
| * <p> The {@code backlog} parameter is the maximum number of pending |
| * connections on the socket. Its exact semantics are implementation specific. |
| * In particular, an implementation may impose a maximum length or may choose |
| * to ignore the parameter altogther. If the {@code backlog} parameter has |
| * the value {@code 0}, or a negative value, then an implementation specific |
| * default is used. |
| * |
| * @param local |
| * The local address to bind the socket, or {@code null} to bind |
| * to an automatically assigned socket address |
| * @param backlog |
| * The maximum number of pending connections |
| * |
| * @return This channel |
| * |
| * @throws AlreadyBoundException |
| * If the socket is already bound |
| * @throws UnsupportedAddressTypeException |
| * If the type of the given address is not supported |
| * @throws SecurityException |
| * If a security manager has been installed and its {@link |
| * SecurityManager#checkListen checkListen} method denies the operation |
| * @throws ClosedChannelException |
| * If the channel is closed |
| * @throws IOException |
| * If some other I/O error occurs |
| */ |
| public abstract AsynchronousServerSocketChannel bind(SocketAddress local, int backlog) |
| throws IOException; |
| |
| /** |
| * @throws IllegalArgumentException {@inheritDoc} |
| * @throws ClosedChannelException {@inheritDoc} |
| * @throws IOException {@inheritDoc} |
| */ |
| public abstract <T> AsynchronousServerSocketChannel setOption(SocketOption<T> name, T value) |
| throws IOException; |
| |
| /** |
| * Accepts a connection. |
| * |
| * <p> This method initiates an asynchronous operation to accept a |
| * connection made to this channel's socket. The {@code handler} parameter is |
| * a completion handler that is invoked when a connection is accepted (or |
| * the operation fails). The result passed to the completion handler is |
| * the {@link AsynchronousSocketChannel} to the new connection. |
| * |
| * <p> When a new connection is accepted then the resulting {@code |
| * AsynchronousSocketChannel} will be bound to the same {@link |
| * AsynchronousChannelGroup} as this channel. If the group is {@link |
| * AsynchronousChannelGroup#isShutdown shutdown} and a connection is accepted, |
| * then the connection is closed, and the operation completes with an {@code |
| * IOException} and cause {@link ShutdownChannelGroupException}. |
| * |
| * <p> To allow for concurrent handling of new connections, the completion |
| * handler is not invoked directly by the initiating thread when a new |
| * connection is accepted immediately (see <a |
| * href="AsynchronousChannelGroup.html#threading">Threading</a>). |
| * |
| * <p> If a security manager has been installed then it verifies that the |
| * address and port number of the connection's remote endpoint are permitted |
| * by the security manager's {@link SecurityManager#checkAccept checkAccept} |
| * method. The permission check is performed with privileges that are restricted |
| * by the calling context of this method. If the permission check fails then |
| * the connection is closed and the operation completes with a {@link |
| * SecurityException}. |
| * |
| * @param <A> |
| * The type of the attachment |
| * @param attachment |
| * The object to attach to the I/O operation; can be {@code null} |
| * @param handler |
| * The handler for consuming the result |
| * |
| * @throws AcceptPendingException |
| * If an accept operation is already in progress on this channel |
| * @throws NotYetBoundException |
| * If this channel's socket has not yet been bound |
| * @throws ShutdownChannelGroupException |
| * If the channel group has terminated |
| */ |
| public abstract <A> void accept(A attachment, |
| CompletionHandler<AsynchronousSocketChannel,? super A> handler); |
| |
| /** |
| * Accepts a connection. |
| * |
| * <p> This method initiates an asynchronous operation to accept a |
| * connection made to this channel's socket. The method behaves in exactly |
| * the same manner as the {@link #accept(Object, CompletionHandler)} method |
| * except that instead of specifying a completion handler, this method |
| * returns a {@code Future} representing the pending result. The {@code |
| * Future}'s {@link Future#get() get} method returns the {@link |
| * AsynchronousSocketChannel} to the new connection on successful completion. |
| * |
| * @return a {@code Future} object representing the pending result |
| * |
| * @throws AcceptPendingException |
| * If an accept operation is already in progress on this channel |
| * @throws NotYetBoundException |
| * If this channel's socket has not yet been bound |
| */ |
| public abstract Future<AsynchronousSocketChannel> accept(); |
| |
| /** |
| * {@inheritDoc} |
| * <p> |
| * If there is a security manager set, its {@code checkConnect} method is |
| * called with the local address and {@code -1} as its arguments to see |
| * if the operation is allowed. If the operation is not allowed, |
| * a {@code SocketAddress} representing the |
| * {@link java.net.InetAddress#getLoopbackAddress loopback} address and the |
| * local port of the channel's socket is returned. |
| * |
| * @return The {@code SocketAddress} that the socket is bound to, or the |
| * {@code SocketAddress} representing the loopback address if |
| * denied by the security manager, or {@code null} if the |
| * channel's socket is not bound |
| * |
| * @throws ClosedChannelException {@inheritDoc} |
| * @throws IOException {@inheritDoc} |
| */ |
| @Override |
| public abstract SocketAddress getLocalAddress() throws IOException; |
| } |