public abstract class ServerSocketChannel extends AbstractSelectableChannel implements NetworkChannel
A selectable channel for stream-oriented listening sockets.
A server-socket channel is created by invoking the open method of this class. It is not possible to create a channel for an arbitrary, pre-existing ServerSocket. A newly-created server-socket channel is open but not yet bound. An attempt to invoke the accept method of an unbound server-socket channel will cause a NotYetBoundException to be thrown. A server-socket channel can be bound by invoking one of the bind methods defined by this class.
Socket options are configured using the setOption method. Server-socket channels support the following options:
| Option Name | Description |
|---|---|
SO_RCVBUF | The size of the socket receive buffer |
SO_REUSEADDR | Re-use address |
Server-socket channels are safe for use by multiple concurrent threads.
protected ServerSocketChannel(SelectorProvider provider)
Initializes a new instance of this class.
provider - The provider that created this channelpublic static ServerSocketChannel open()
throws IOException Opens a server-socket channel.
The new channel is created by invoking the openServerSocketChannel method of the system-wide default SelectorProvider object.
The new channel's socket is initially unbound; it must be bound to a specific address via one of its socket's bind methods before connections can be accepted.
IOException - If an I/O error occurspublic final int validOps()
Returns an operation set identifying this channel's supported operations.
Server-socket channels only support the accepting of new connections, so this method returns SelectionKey.OP_ACCEPT.
validOps in class SelectableChannel
public final ServerSocketChannel bind(SocketAddress local)
throws IOException Binds the channel's socket to a local address and configures the socket to listen for connections.
An invocation of this method is equivalent to the following:
bind(local, 0);
bind in interface NetworkChannel
local - The local address to bind the socket, or null to bind to an automatically assigned socket addressAlreadyBoundException - If the socket is already boundUnsupportedAddressTypeException - If the type of the given address is not supportedClosedChannelException - If the channel is closedIOException - If some other I/O error occursSecurityException - If a security manager has been installed and its checkListen method denies the operationNetworkChannel.getLocalAddress()public abstract ServerSocketChannel bind(SocketAddress local,
int backlog)
throws IOException Binds the channel's socket to a local address and configures the socket to listen for connections.
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 channel is closed.
The 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 backlog parameter has the value 0, or a negative value, then an implementation specific default is used.
local - The address to bind the socket, or null to bind to an automatically assigned socket addressbacklog - The maximum number of pending connectionsAlreadyBoundException - If the socket is already boundUnsupportedAddressTypeException - If the type of the given address is not supportedClosedChannelException - If this channel is closedIOException - If some other I/O error occursSecurityException - If a security manager has been installed and its checkListen method denies the operationpublic abstract <T> ServerSocketChannel setOption(SocketOption<T> name,
T value)
throws IOException Description copied from interface: NetworkChannel
Sets the value of a socket option.
setOption in interface NetworkChannel
T - The type of the socket option valuename - The socket optionvalue - The value of the socket option. A value of null may be a valid value for some socket options.UnsupportedOperationException - If the socket option is not supported by this channelIllegalArgumentException - If the value is not a valid value for this socket optionClosedChannelException - If this channel is closedIOException - If an I/O error occursStandardSocketOptionspublic abstract ServerSocket socket()
Retrieves a server socket associated with this channel.
The returned object will not declare any public methods that are not declared in the ServerSocket class.
public abstract SocketChannel accept()
throws IOException Accepts a connection made to this channel's socket.
If this channel is in non-blocking mode then this method will immediately return null if there are no pending connections. Otherwise it will block indefinitely until a new connection is available or an I/O error occurs.
The socket channel returned by this method, if any, will be in blocking mode regardless of the blocking mode of this channel.
This method performs exactly the same security checks as the accept method of the ServerSocket class. That is, if a security manager has been installed then for each new connection this method verifies that the address and port number of the connection's remote endpoint are permitted by the security manager's checkAccept method.
null if this channel is in non-blocking mode and no connection is available to be acceptedClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel while the accept operation is in progressClosedByInterruptException - If another thread interrupts the current thread while the accept operation is in progress, thereby closing the channel and setting the current thread's interrupt statusNotYetBoundException - If this channel's socket has not yet been boundSecurityException - If a security manager has been installed and it does not permit access to the remote endpoint of the new connectionIOException - If some other I/O error occurspublic abstract SocketAddress getLocalAddress()
throws IOException Returns the socket address that this channel's socket is bound to.
Where the channel is bound to an Internet Protocol socket address then the return value from this method is of type InetSocketAddress.
If there is a security manager set, its checkConnect method is called with the local address and -1 as its arguments to see if the operation is allowed. If the operation is not allowed, a SocketAddress representing the loopback address and the local port of the channel's socket is returned.
getLocalAddress in interface NetworkChannel
SocketAddress that the socket is bound to, or the SocketAddress representing the loopback address if denied by the security manager, or null if the channel's socket is not boundClosedChannelException - If the channel is closedIOException - If an I/O error occurs
© 1993–2017, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.