Listens for a connection to be made to this socket and accepts it.

  Listens for a connection to be made to this socket and accepts it. The method blocks until a connection is made.

A new Socket s is created and, if there is a security manager, the security manager's checkAccept method is called with s.getInetAddress().getHostAddress() and s.getPort() as its arguments to ensure the operation is allowed. This could result in a SecurityException.
Returns: the new Socket
Throws:
- IOException - if an I/O error occurs when waiting for a connection.
- SecurityException - if a security manager exists and its checkAccept method doesn't allow the operation.
- SocketTimeoutException - if a timeout was previously set with setSoTimeout and the timeout has been reached.
- java.nio.channels.IllegalBlockingModeException - if this socket has an associated channel, the channel is in non-blocking mode, and there is no connection ready to be accepted
See Also: SecurityManager.checkAccept(java.lang.String, int),

  Binds the ServerSocket to a specific address (IP address and port number).

  Binds the ServerSocket to a specific address (IP address and port number).

If the address is null, then the system will pick up an ephemeral port and a valid local address to bind the socket.

Parameters:
- endpoint - The IP address & port number to bind to.
Throws:
- IOException - if the bind operation fails, or if the socket is already bound.
- SecurityException - if a SecurityManager is present and its checkListen method doesn't allow the operation.
- IllegalArgumentException - if endpoint is a SocketAddress subclass not supported by this socket
Since: 1.4

  Binds the ServerSocket to a specific address (IP address and port number).

  Binds the ServerSocket to a specific address (IP address and port number).

If the address is null, then the system will pick up an ephemeral port and a valid local address to bind the socket.

The backlog argument must be a positive value greater than 0. If the value passed if equal or less than 0, then the default value will be assumed.
Parameters:
- endpoint - The IP address & port number to bind to.
- backlog - The listen backlog length.
Throws:
- IOException - if the bind operation fails, or if the socket is already bound.
- SecurityException - if a SecurityManager is present and its checkListen method doesn't allow the operation.
- IllegalArgumentException - if endpoint is a SocketAddress subclass not supported by this socket
Since: 1.4

  Closes this socket.

  Closes this socket. Any thread currently blocked in ServerSocket.accept() will throw a SocketException.

If this socket has an associated channel then the channel is closed as well.
Throws:
- IOException - if an I/O error occurs when closing the socket.

  Creates the socket implementation.

  Creates the socket implementation.
Throws:
- IOException - if creation fails
Since: 1.4

  Returns the unique ServerSocketChannel object associated with this socket, if any.

  Returns the unique ServerSocketChannel object associated with this socket, if any.

A server socket will have a channel if, and only if, the channel itself was created via the ServerSocketChannel.open method.
Returns: the server-socket channel associated with this socket, or null if this socket was not created for a channel
Since: 1.4

  Get the SocketImpl attached to this socket, creating it if necessary.

  Get the SocketImpl attached to this socket, creating
it if necessary.
Returns: the SocketImpl attached to that ServerSocket.
Throws:
- SocketException - if creation fails.
Since: 1.4

  Returns the local address of this server socket.

  Returns the local address of this server socket.
Returns: the address to which this socket is bound, or null if the socket is unbound.

  Returns the port on which this socket is listening.

  Returns the port on which this socket is listening.
Returns: the port number to which this socket is listening or -1 if the socket is not bound yet.

  Returns the address of the endpoint this socket is bound to, or null if it is not bound yet.

  Returns the address of the endpoint this socket is bound to, or
null if it is not bound yet.
Returns: a SocketAddress representing the local endpoint of this socket, or null if it is not bound yet.
Since: 1.4
See Also: ServerSocket.getInetAddress(), ServerSocket.getLocalPort(), ServerSocket.bind(SocketAddress),

  Gets the value of the SO_RCVBUF option for this ServerSocket, that is the proposed buffer size that will be used for Sockets accepted from this ServerSocket.

  Gets the value of the SO_RCVBUF option for this ServerSocket, that is the proposed buffer size that will be used for Sockets accepted from this ServerSocket.

Note, the value actually set in the accepted socket is determined by calling Socket.getReceiveBufferSize().
Returns: the value of the SO_RCVBUF option for this Socket.
Throws:
- SocketException - if there is an error in the underlying protocol, such as a TCP error.
Since: 1.4
See Also: ServerSocket.setReceiveBufferSize(int),

  Tests if SO_REUSEADDR is enabled.

  Tests if SO_REUSEADDR is enabled.
Returns: a boolean indicating whether or not SO_REUSEADDR is enabled.
Throws:
- SocketException - if there is an error in the underlying protocol, such as a TCP error.
Since: 1.4
See Also: ServerSocket.setReuseAddress(boolean),

  Retrieve setting for SO_TIMEOUT.

  Retrieve setting for SO_TIMEOUT. 0 returns implies that the
option is disabled (i.e., timeout of infinity).
Returns: the SO_TIMEOUT value
Throws:
- IOException - if an I/O error occurs
Since: JDK1.1
See Also: ServerSocket.setSoTimeout(int),

  Subclasses of ServerSocket use this method to override accept() to return their own subclass of socket.

  Subclasses of ServerSocket use this method to override accept()
to return their own subclass of socket. So a FooServerSocket
will typically hand this method an empty FooSocket. On
return from implAccept the FooSocket will be connected to a client.
Parameters:
- s - the Socket
Throws:
- java.nio.channels.IllegalBlockingModeException - if this socket has an associated channel, and the channel is in non-blocking mode
- IOException - if an I/O error occurs when waiting for a connection.
Since: JDK1.1

  Returns the binding state of the ServerSocket.

  Returns the binding state of the ServerSocket.
Returns: true if the ServerSocket succesfuly bound to an address
Since: 1.4

  Returns the closed state of the ServerSocket.

  Returns the closed state of the ServerSocket.
Returns: true if the socket has been closed
Since: 1.4

  Sets performance preferences for this ServerSocket.

  Sets performance preferences for this ServerSocket.

Sockets use the TCP/IP protocol by default. Some implementations may offer alternative protocols which have different performance characteristics than TCP/IP. This method allows the application to express its own preferences as to how these tradeoffs should be made when the implementation chooses from the available protocols.

Performance preferences are described by three integers whose values indicate the relative importance of short connection time, low latency, and high bandwidth. The absolute values of the integers are irrelevant; in order to choose a protocol the values are simply compared, with larger values indicating stronger preferences. If the application prefers short connection time over both low latency and high bandwidth, for example, then it could invoke this method with the values (1, 0, 0). If the application prefers high bandwidth above low latency, and low latency above short connection time, then it could invoke this method with the values (0, 1, 2).

Invoking this method after this socket has been bound will have no effect. This implies that in order to use this capability requires the socket to be created with the no-argument constructor.
Parameters:
- connectionTime - An int expressing the relative importance of a short connection time
- latency - An int expressing the relative importance of low latency
- bandwidth - An int expressing the relative importance of high bandwidth
Since: 1.5

  Sets a default proposed value for the SO_RCVBUF option for sockets accepted from this ServerSocket.

  Sets a default proposed value for the SO_RCVBUF option for sockets accepted from this ServerSocket. The value actually set in the accepted socket must be determined by calling Socket.getReceiveBufferSize() after the socket is returned by ServerSocket.accept().

The value of SO_RCVBUF is used both to set the size of the internal socket receive buffer, and to set the size of the TCP receive window that is advertized to the remote peer.

It is possible to change the value subsequently, by calling Socket.setReceiveBufferSize(int). However, if the application wishes to allow a receive window larger than 64K bytes, as defined by RFC1323 then the proposed value must be set in the ServerSocket before it is bound to a local address. This implies, that the ServerSocket must be created with the no-argument constructor, then setReceiveBufferSize() must be called and lastly the ServerSocket is bound to an address by calling bind().

Failure to do this will not cause an error, and the buffer size may be set to the requested value but the TCP receive window in sockets accepted from this ServerSocket will be no larger than 64K bytes.
Parameters:
- size - the size to which to set the receive buffer size. This value must be greater than 0.
Throws:
- SocketException - if there is an error in the underlying protocol, such as a TCP error.
- IllegalArgumentException - if the value is 0 or is negative.
Since: 1.4
See Also: ServerSocket.getReceiveBufferSize(),

  Enable/disable the SO_REUSEADDR socket option.

  Enable/disable the SO_REUSEADDR socket option.

When a TCP connection is closed the connection may remain in a timeout state for a period of time after the connection is closed (typically known as the TIME_WAIT state or 2MSL wait state). For applications using a well known socket address or port it may not be possible to bind a socket to the required SocketAddress if there is a connection in the timeout state involving the socket address or port.

Enabling SO_REUSEADDR prior to binding the socket using ServerSocket.bind(SocketAddress) allows the socket to be bound even though a previous connection is in a timeout state.

When a ServerSocket is created the initial setting of SO_REUSEADDR is not defined. Applications can use ServerSocket.getReuseAddress() to determine the initial setting of SO_REUSEADDR.

The behaviour when SO_REUSEADDR is enabled or disabled after a socket is bound (See ServerSocket.isBound()) is not defined.
Parameters:
- on - whether to enable or disable the socket option
Throws:
- SocketException - if an error occurs enabling or disabling the SO_RESUEADDR socket option, or the socket is closed.
Since: 1.4
See Also: ServerSocket.getReuseAddress(), ServerSocket.bind(SocketAddress), ServerSocket.isBound(), ServerSocket.isClosed(),

  Sets the server socket implementation factory for the application.

  Sets the server socket implementation factory for the application. The factory can be specified only once.

When an application creates a new server socket, the socket implementation factory's createSocketImpl method is called to create the actual socket implementation.

Passing null to the method is a no-op unless the factory was already set.

If there is a security manager, this method first calls the security manager's checkSetFactory method to ensure the operation is allowed. This could result in a SecurityException.
Parameters:
- fac - the desired factory.
Throws:
- IOException - if an I/O error occurs when setting the socket factory.
- SocketException - if the factory has already been defined.
- SecurityException - if a security manager exists and its checkSetFactory method doesn't allow the operation.
See Also: SocketImplFactory.createSocketImpl(), SecurityManager.checkSetFactory(),

  Enable/disable SO_TIMEOUT with the specified timeout, in milliseconds.

  Enable/disable SO_TIMEOUT with the specified timeout, in
milliseconds. With this option set to a non-zero timeout,
a call to accept() for this ServerSocket
will block for only this amount of time. If the timeout expires,
a java.net.SocketTimeoutException is raised, though the
ServerSocket is still valid. The option must be enabled
prior to entering the blocking operation to have effect. The
timeout must be > 0.
A timeout of zero is interpreted as an infinite timeout.
Parameters:
- timeout - the specified timeout, in milliseconds
Throws:
- SocketException - if there is an error in the underlying protocol, such as a TCP error.
Since: JDK1.1
See Also: ServerSocket.getSoTimeout(),

  Returns the implementation address and implementation port of this socket as a String.

  Returns the implementation address and implementation port of
this socket as a String.
Returns: a string representation of this socket.