java.net.Socket Maven / Gradle / Ivy
/*
This is not an official specification document, and usage is restricted.
NOTICE
(c) 2005-2007 Sun Microsystems, Inc. All Rights Reserved.
Neither this file nor any files generated from it describe a complete
specification, and they may only be used as described below. For
example, no permission is given for you to incorporate this file, in
whole or in part, in an implementation of a Java specification.
Sun Microsystems Inc. owns the copyright in this file and it is provided
to you for informative, as opposed to normative, use. The file and any
files generated from it may be used to generate other informative
documentation, such as a unified set of documents of API signatures for
a platform that includes technologies expressed as Java APIs. The file
may also be used to produce "compilation stubs," which allow
applications to be compiled and validated for such platforms.
Any work generated from this file, such as unified javadocs or compiled
stub files, must be accompanied by this notice in its entirety.
This work corresponds to the API signatures of JSR 219: Foundation
Profile 1.1. In the event of a discrepency between this work and the
JSR 219 specification, which is available at
http://www.jcp.org/en/jsr/detail?id=219, the latter takes precedence.
*/
package java.net;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.security.AccessController;
import java.security.PrivilegedExceptionAction;
/**
* This class implements client sockets (also called just
* "sockets"). A socket is an endpoint for communication
* between two machines.
*
* The actual work of the socket is performed by an instance of the
* SocketImpl class. An application, by changing
* the socket factory that creates the socket implementation,
* can configure itself to create sockets appropriate to the local
* firewall.
*
* @author unascribed
* @version 1.56, 08/09/01
* @see java.net.Socket#setSocketImplFactory(java.net.SocketImplFactory)
* @see java.net.SocketImpl
* @since JDK1.0
*/
public class Socket
{
/**
* Creates an unconnected socket, with the
* system-default type of SocketImpl.
*
* @since JDK1.1
* @revised 1.4
*/
public Socket() { }
/**
* Creates an unconnected Socket with a user-specified
* SocketImpl.
*
* @param impl an instance of a SocketImpl
* the subclass wishes to use on the Socket.
*
* @exception SocketException if there is an error in the underlying protocol,
* such as a TCP error.
* @since JDK1.1
*/
protected Socket(SocketImpl impl) throws SocketException { }
/**
* Creates a stream socket and connects it to the specified port
* number on the named host.
*
* If the specified host is null it is the equivalent of
* specifying the address as {@link java.net.InetAddress#getByName InetAddress.getByName}(null).
* In other words, it is equivalent to specifying an address of the
* loopback interface.
*
* If the application has specified a server socket factory, that
* factory's createSocketImpl method is called to create
* the actual socket implementation. Otherwise a "plain" socket is created.
*
* If there is a security manager, its
* checkConnect method is called
* with the host address and port
* as its arguments. This could result in a SecurityException.
*
* @param host the host name, or null for the loopback address.
* @param port the port number.
*
* @exception UnknownHostException if the IP address of
* the host could not be determined.
*
* @exception IOException if an I/O error occurs when creating the socket.
* @exception SecurityException if a security manager exists and its
* checkConnect method doesn't allow the operation.
* @see java.net.Socket#setSocketImplFactory(java.net.SocketImplFactory)
* @see java.net.SocketImpl
* @see java.net.SocketImplFactory#createSocketImpl()
* @see SecurityManager#checkConnect
*/
public Socket(String host, int port)
throws UnknownHostException, IOException
{ }
/**
* Creates a stream socket and connects it to the specified port
* number at the specified IP address.
*
* If the application has specified a socket factory, that factory's
* createSocketImpl method is called to create the
* actual socket implementation. Otherwise a "plain" socket is created.
*
* If there is a security manager, its
* checkConnect method is called
* with the host address and port
* as its arguments. This could result in a SecurityException.
*
* @param address the IP address.
* @param port the port number.
* @exception IOException if an I/O error occurs when creating the socket.
* @exception SecurityException if a security manager exists and its
* checkConnect method doesn't allow the operation.
* @see java.net.Socket#setSocketImplFactory(java.net.SocketImplFactory)
* @see java.net.SocketImpl
* @see java.net.SocketImplFactory#createSocketImpl()
* @see SecurityManager#checkConnect
*/
public Socket(InetAddress address, int port) throws IOException { }
/**
* Creates a socket and connects it to the specified remote host on
* the specified remote port. The Socket will also bind() to the local
* address and port supplied.
*
* If the specified host is null it is the equivalent of
* specifying the address as {@link java.net.InetAddress#getByName InetAddress.getByName}(null).
* In other words, it is equivalent to specifying an address of the
* loopback interface.
*
* If there is a security manager, its
* checkConnect method is called
* with the host address and port
* as its arguments. This could result in a SecurityException.
*
* @param host the name of the remote host, or null for the loopback address.
* @param port the remote port
* @param localAddr the local address the socket is bound to
* @param localPort the local port the socket is bound to
* @exception IOException if an I/O error occurs when creating the socket.
* @exception SecurityException if a security manager exists and its
* checkConnect method doesn't allow the operation.
* @see SecurityManager#checkConnect
* @since JDK1.1
*/
public Socket(String host, int port, InetAddress localAddr, int localPort)
throws IOException
{ }
/**
* Creates a socket and connects it to the specified remote address on
* the specified remote port. The Socket will also bind() to the local
* address and port supplied.
*
* If there is a security manager, its
* checkConnect method is called
* with the host address and port
* as its arguments. This could result in a SecurityException.
*
* @param address the remote address
* @param port the remote port
* @param localAddr the local address the socket is bound to
* @param localPort the local port the socket is bound to
* @exception IOException if an I/O error occurs when creating the socket.
* @exception SecurityException if a security manager exists and its
* checkConnect method doesn't allow the operation.
* @see SecurityManager#checkConnect
* @since JDK1.1
*/
public Socket(InetAddress address, int port, InetAddress localAddr, int
localPort) throws IOException
{ }
/**
* Connects this socket to the server.
*
* @param endpoint the SocketAddress
* @throws IOException if an error occurs during the connection
* @throws IllegalArgumentException if endpoint is null or is a
* SocketAddress subclass not supported by this socket
* @since 1.4
* @spec JSR-51
*/
public void connect(SocketAddress endpoint) throws IOException { }
/**
* Connects this socket to the server with a specified timeout value.
* A timeout of zero is interpreted as an infinite timeout. The connection
* will then block until established or an error occurs.
*
* @param endpoint the SocketAddress
* @param timeout the timeout value to be used in milliseconds.
* @throws IOException if an error occurs during the connection
* @throws SocketTimeoutException if timeout expires before connecting
* @throws IllegalArgumentException if endpoint is null or is a
* SocketAddress subclass not supported by this socket
* @since 1.4
* @spec JSR-51
*/
public void connect(SocketAddress endpoint, int timeout) throws IOException
{ }
/**
* Binds the socket to a local address.
*
* If the address is null, then the system will pick up
* an ephemeral port and a valid local address to bind the socket.
*
* @param bindpoint the SocketAddress to bind to
* @throws IOException if the bind operation fails, or if the socket
* is already bound.
* @throws IllegalArgumentException if bindpoint is a
* SocketAddress subclass not supported by this socket
*
* @since 1.4
* @see #isBound
*/
public void bind(SocketAddress bindpoint) throws IOException { }
/**
* Returns the address to which the socket is connected.
*
* @return the remote IP address to which this socket is connected,
* or null if the socket is not connected.
*/
public InetAddress getInetAddress() {
return null;
}
/**
* Gets the local address to which the socket is bound.
*
* @return the local address to which the socket is bound or
* InetAddress.anyLocalAddress()
* if the socket is not bound yet.
* @since JDK1.1
*/
public InetAddress getLocalAddress() {
return null;
}
/**
* Returns the remote port to which this socket is connected.
*
* @return the remote port number to which this socket is connected, or
* 0 if the socket is not connected yet.
*/
public int getPort() {
return 0;
}
/**
* Returns the local port to which this socket is bound.
*
* @return the local port number to which this socket is bound or -1
* if the socket is not bound yet.
*/
public int getLocalPort() {
return 0;
}
/**
* Returns the address of the endpoint this socket is connected to, or
* null if it is unconnected.
* @return a SocketAddress reprensenting the remote endpoint of this
* socket, or null if it is not connected yet.
* @see #getInetAddress()
* @see #getPort()
* @see #connect(SocketAddress, int)
* @see #connect(SocketAddress)
* @since 1.4
*/
public SocketAddress getRemoteSocketAddress() {
return null;
}
/**
* Returns the address of the endpoint this socket is bound to, or
* null if it is not bound yet.
*
* @return a SocketAddress representing the local endpoint of this
* socket, or null if it is not bound yet.
* @see #getLocalAddress()
* @see #getLocalPort()
* @see #bind(SocketAddress)
* @since 1.4
*/
public SocketAddress getLocalSocketAddress() {
return null;
}
/**
* Returns an input stream for this socket.
*
*
If this socket has an associated channel then the resulting input
* stream delegates all of its operations to the channel.
*
*
Under abnormal conditions the underlying connection may be
* broken by the remote host or the network software (for example
* a connection reset in the case of TCP connections). When a
* broken connection is detected by the network software the
* following applies to the returned input stream :-
*
*
*
* The network software may discard bytes that are buffered
* by the socket. Bytes that aren't discarded by the network
* software can be read using {@link java.io.InputStream#read read}.
*
*
If there are no bytes buffered on the socket, or all
* buffered bytes have been consumed by
* {@link java.io.InputStream#read read}, then all subsequent
* calls to {@link java.io.InputStream#read read} will throw an
* {@link java.io.IOException IOException}.
*
*
If there are no bytes buffered on the socket, and the
* socket has not been closed using {@link #close close}, then
* {@link java.io.InputStream#available available} will
* return 0.
*
*
*
* @return an input stream for reading bytes from this socket.
* @exception IOException if an I/O error occurs when creating the
* input stream, the socket is closed, the socket is
* not connected, or the socket input has been shutdown
* using {@link #shutdownInput()}
*
* @revised 1.4
* @spec JSR-51
*/
public InputStream getInputStream() throws IOException {
return null;
}
/**
* Returns an output stream for this socket.
*
* If this socket has an associated channel then the resulting output
* stream delegates all of its operations to the channel.
*
* @return an output stream for writing bytes to this socket.
* @exception IOException if an I/O error occurs when creating the
* output stream or if the socket is not connected.
* @revised 1.4
* @spec JSR-51
*/
public OutputStream getOutputStream() throws IOException {
return null;
}
/**
* Enable/disable TCP_NODELAY (disable/enable Nagle's algorithm).
*
* @param on true to enable TCP_NODELAY,
* false to disable.
*
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
*
* @since JDK1.1
*
* @see #getTcpNoDelay()
*/
public void setTcpNoDelay(boolean on) throws SocketException { }
/**
* Tests if TCP_NODELAY is enabled.
*
* @return a boolean indicating whether or not TCP_NODELAY is enabled.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since JDK1.1
* @see #setTcpNoDelay(boolean)
*/
public boolean getTcpNoDelay() throws SocketException {
return false;
}
/**
* Enable/disable SO_LINGER with the specified linger time in seconds.
* The maximum timeout value is platform specific.
*
* The setting only affects socket close.
*
* @param on whether or not to linger on.
* @param linger how long to linger for, if on is true.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @exception IllegalArgumentException if the linger value is negative.
* @since JDK1.1
* @see #getSoLinger()
*/
public void setSoLinger(boolean on, int linger) throws SocketException { }
/**
* Returns setting for SO_LINGER. -1 returns implies that the
* option is disabled.
*
* The setting only affects socket close.
*
* @return the setting for SO_LINGER.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since JDK1.1
* @see #setSoLinger(boolean, int)
*/
public int getSoLinger() throws SocketException {
return 0;
}
/**
* Send one byte of urgent data on the socket. The byte to be sent is the lowest eight
* bits of the data parameter. The urgent byte is
* sent after any preceding writes to the socket OutputStream
* and before any future writes to the OutputStream.
* @param data The byte of data to send
* @exception IOException if there is an error
* sending the data.
* @since 1.4
*/
public void sendUrgentData(int data) throws IOException { }
/**
* Enable/disable OOBINLINE (receipt of TCP urgent data)
*
* By default, this option is disabled and TCP urgent data received on a
* socket is silently discarded. If the user wishes to receive urgent data, then
* this option must be enabled. When enabled, urgent data is received
* inline with normal data.
*
* Note, only limited support is provided for handling incoming urgent
* data. In particular, no notification of incoming urgent data is provided
* and there is no capability to distinguish between normal data and urgent
* data unless provided by a higher level protocol.
*
* @param on true to enable OOBINLINE,
* false to disable.
*
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
*
* @since 1.4
*
* @see #getOOBInline()
*/
public void setOOBInline(boolean on) throws SocketException { }
/**
* Tests if OOBINLINE is enabled.
*
* @return a boolean indicating whether or not OOBINLINE is enabled.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since 1.4
* @see #setOOBInline(boolean)
*/
public boolean getOOBInline() throws SocketException {
return false;
}
/**
* Enable/disable SO_TIMEOUT with the specified timeout, in
* milliseconds. With this option set to a non-zero timeout,
* a read() call on the InputStream associated with this Socket
* will block for only this amount of time. If the timeout expires,
* a java.net.SocketTimeoutException is raised, though the
* Socket 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.
* @param timeout the specified timeout, in milliseconds.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since JDK 1.1
* @see #getSoTimeout()
*/
public synchronized void setSoTimeout(int timeout) throws SocketException
{ }
/**
* Returns setting for SO_TIMEOUT. 0 returns implies that the
* option is disabled (i.e., timeout of infinity).
* @return the setting for SO_TIMEOUT
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since JDK1.1
* @see #setSoTimeout(int)
*/
public synchronized int getSoTimeout() throws SocketException {
return 0;
}
/**
* Sets the SO_SNDBUF option to the specified value for this
* Socket. The SO_SNDBUF option is used by the platform's
* networking code as a hint for the size to set
* the underlying network I/O buffers.
*
*
Because SO_SNDBUF is a hint, applications that want to
* verify what size the buffers were set to should call
* {@link #getSendBufferSize()}.
*
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
*
* @param size the size to which to set the send buffer
* size. This value must be greater than 0.
*
* @exception IllegalArgumentException if the
* value is 0 or is negative.
*
* @see #getSendBufferSize()
* @since 1.2
*/
public synchronized void setSendBufferSize(int size) throws SocketException
{ }
/**
* Get value of the SO_SNDBUF option for this Socket,
* that is the buffer size used by the platform
* for output on this Socket.
* @return the value of the SO_SNDBUF option for this Socket.
*
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
*
* @see #setSendBufferSize(int)
* @since 1.2
*/
public synchronized int getSendBufferSize() throws SocketException {
return 0;
}
/**
* Sets the SO_RCVBUF option to the specified value for this
* Socket. The SO_RCVBUF option is used by the platform's
* networking code as a hint for the size to set
* the underlying network I/O buffers.
*
*
Increasing the receive buffer size can increase the performance of
* network I/O for high-volume connection, while decreasing it can
* help reduce the backlog of incoming data.
*
*
Because SO_RCVBUF is a hint, applications that want to
* verify what size the buffers were set to should call
* {@link #getReceiveBufferSize()}.
*
*
The value of SO_RCVBUF is also used to set the TCP receive window
* that is advertized to the remote peer. Generally, the window size
* can be modified at any time when a socket is connected. However, if
* a receive window larger than 64K is required then this must be requested
* before the socket is connected to the remote peer. There are two
* cases to be aware of:
*
* - For sockets accepted from a ServerSocket, this must be done by calling
* {@link ServerSocket#setReceiveBufferSize(int)} before the ServerSocket
* is bound to a local address.
* - For client sockets, setReceiveBufferSize() must be called before
* connecting the socket to its remote peer.
* @param size the size to which to set the receive buffer
* size. This value must be greater than 0.
*
* @exception IllegalArgumentException if the value is 0 or is
* negative.
*
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
*
* @see #getReceiveBufferSize()
* @see ServerSocket#setReceiveBufferSize(int)
* @since 1.2
*/
public synchronized void setReceiveBufferSize(int size)
throws SocketException
{ }
/**
* Gets the value of the SO_RCVBUF option for this Socket,
* that is the buffer size used by the platform for
* input on this Socket.
*
* @return the value of the SO_RCVBUF option for this Socket.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @see #setReceiveBufferSize(int)
* @since 1.2
*/
public synchronized int getReceiveBufferSize() throws SocketException {
return 0;
}
/**
* Enable/disable SO_KEEPALIVE.
*
* @param on whether or not to have socket keep alive turned on.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since 1.3
* @see #getKeepAlive()
*/
public void setKeepAlive(boolean on) throws SocketException { }
/**
* Tests if SO_KEEPALIVE is enabled.
*
* @return a boolean indicating whether or not SO_KEEPALIVE is enabled.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since 1.3
* @see #setKeepAlive(boolean)
*/
public boolean getKeepAlive() throws SocketException {
return false;
}
/**
* Sets traffic class or type-of-service octet in the IP
* header for packets sent from this Socket.
* As the underlying network implementation may ignore this
* value applications should consider it a hint.
*
* The tc must be in the range 0 <= tc <=
* 255 or an IllegalArgumentException will be thrown.
*
Notes:
*
for Internet Protocol v4 the value consists of an octet
* with precedence and TOS fields as detailed in RFC 1349. The
* TOS field is bitset created by bitwise-or'ing values such
* the following :-
*
*
* IPTOS_LOWCOST (0x02)IPTOS_RELIABILITY (0x04)IPTOS_THROUGHPUT (0x08)IPTOS_LOWDELAY (0x10)
* The last low order bit is always ignored as this
* corresponds to the MBZ (must be zero) bit.
*
* Setting bits in the precedence field may result in a
* SocketException indicating that the operation is not
* permitted.
*
* for Internet Protocol v6 tc is the value that
* would be placed into the sin6_flowinfo field of the IP header.
*
* @param tc an int value for the bitset.
* @throws SocketException if there is an error setting the
* traffic class or type-of-service
* @since 1.4
* @see #getTrafficClass
*/
public void setTrafficClass(int tc) throws SocketException { }
/**
* Gets traffic class or type-of-service in the IP header
* for packets sent from this Socket
*
* As the underlying network implementation may ignore the
* traffic class or type-of-service set using {@link #setTrafficClass()}
* this method may return a different value than was previously
* set using the {@link #setTrafficClass()} method on this Socket.
*
* @return the traffic class or type-of-service already set
* @throws SocketException if there is an error obtaining the
* traffic class or type-of-service value.
* @since 1.4
* @see #setTrafficClass
*/
public int getTrafficClass() throws SocketException {
return 0;
}
/**
* 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 {@link #bind(SocketAddress)} allows the socket to be
* bound even though a previous connection is in a timeout
* state.
*
* When a Socket is created the initial setting
* of SO_REUSEADDR is disabled.
*
* The behaviour when SO_REUSEADDR is enabled or
* disabled after a socket is bound (See {@link #isBound()})
* is not defined.
*
* @param on whether to enable or disable the socket option
* @exception SocketException if an error occurs enabling or
* disabling the SO_RESUEADDR socket option,
* or the socket is closed.
* @since 1.4
* @see #getReuseAddress()
* @see #bind(SocketAddress)
* @see #isClosed()
* @see #isBound()
*/
public void setReuseAddress(boolean on) throws SocketException { }
/**
* Tests if SO_REUSEADDR is enabled.
*
* @return a boolean indicating whether or not SO_REUSEADDR is enabled.
* @exception SocketException if there is an error
* in the underlying protocol, such as a TCP error.
* @since 1.4
* @see #setReuseAddress(boolean)
*/
public boolean getReuseAddress() throws SocketException {
return false;
}
/**
* Closes this socket.
*
* Any thread currently blocked in an I/O operation upon this socket
* will throw a {@link SocketException}.
*
* Once a socket has been closed, it is not available for further networking
* use (i.e. can't be reconnected or rebound). A new socket needs to be
* created.
*
*
If this socket has an associated channel then the channel is closed
* as well.
*
* @exception IOException if an I/O error occurs when closing this socket.
* @revised 1.4
* @spec JSR-51
* @see #isClosed
*/
public synchronized void close() throws IOException { }
/**
* Places the input stream for this socket at "end of stream".
* Any data sent to the input stream side of the socket is acknowledged
* and then silently discarded.
*
* If you read from a socket input stream after invoking
* shutdownInput() on the socket, the stream will return EOF.
*
* @exception IOException if an I/O error occurs when shutting down this
* socket.
*
* @since 1.3
* @see java.net.Socket#shutdownOutput()
* @see java.net.Socket#close()
* @see java.net.Socket#setSoLinger(boolean, int)
* @see #isInputShutdown
*/
public void shutdownInput() throws IOException { }
/**
* Disables the output stream for this socket.
* For a TCP socket, any previously written data will be sent
* followed by TCP's normal connection termination sequence.
*
* If you write to a socket output stream after invoking
* shutdownOutput() on the socket, the stream will throw
* an IOException.
*
* @exception IOException if an I/O error occurs when shutting down this
* socket.
*
* @since 1.3
* @see java.net.Socket#shutdownInput()
* @see java.net.Socket#close()
* @see java.net.Socket#setSoLinger(boolean, int)
* @see #isOutputShutdown
*/
public void shutdownOutput() throws IOException { }
/**
* Converts this socket to a String.
*
* @return a string representation of this socket.
*/
public String toString() {
return null;
}
/**
* Returns the connection state of the socket.
*
* @return true if the socket successfuly connected to a server
* @since 1.4
*/
public boolean isConnected() {
return false;
}
/**
* Returns the binding state of the socket.
*
* @return true if the socket successfuly bound to an address
* @since 1.4
* @see #bind
*/
public boolean isBound() {
return false;
}
/**
* Returns the closed state of the socket.
*
* @return true if the socket has been closed
* @since 1.4
* @see #close
*/
public boolean isClosed() {
return false;
}
/**
* Returns wether the read-half of the socket connection is closed.
*
* @return true if the input of the socket has been shutdown
* @since 1.4
* @see #shutdownInput
*/
public boolean isInputShutdown() {
return false;
}
/**
* Returns wether the write-half of the socket connection is closed.
*
* @return true if the output of the socket has been shutdown
* @since 1.4
* @see #shutdownOutput
*/
public boolean isOutputShutdown() {
return false;
}
/**
* Sets the client socket implementation factory for the
* application. The factory can be specified only once.
*
* When an application creates a new client socket, the socket
* implementation factory's createSocketImpl method is
* called to create the actual socket implementation.
*
*
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.
*
* @param fac the desired factory.
* @exception IOException if an I/O error occurs when setting the
* socket factory.
* @exception SocketException if the factory is already defined.
* @exception SecurityException if a security manager exists and its
* checkSetFactory method doesn't allow the operation.
* @see java.net.SocketImplFactory#createSocketImpl()
* @see SecurityManager#checkSetFactory
*/
public static synchronized void setSocketImplFactory(SocketImplFactory fac)
throws IOException
{ }
}