SocketOptions
public abstract class SocketImpl extends Object implements SocketOptions
SocketImpl
is a common superclass of all classes that actually implement sockets. It is used to create both client and server sockets.Modifier and Type | Field | Description |
---|---|---|
protected InetAddress |
address |
The IP address of the remote end of this socket. |
protected FileDescriptor |
fd |
The file descriptor object for this socket. |
protected int |
localport |
The local port number to which this socket is connected. |
protected int |
port |
The port number on the remote host to which this socket is connected. |
IP_MULTICAST_IF, IP_MULTICAST_IF2, IP_MULTICAST_LOOP, IP_TOS, SO_BINDADDR, SO_BROADCAST, SO_KEEPALIVE, SO_LINGER, SO_OOBINLINE, SO_RCVBUF, SO_REUSEADDR, SO_REUSEPORT, SO_SNDBUF, SO_TIMEOUT, TCP_NODELAY
Constructor | Description |
---|---|
SocketImpl() |
Initialize a new instance of this class |
Modifier and Type | Method | Description |
---|---|---|
protected abstract void |
accept |
Accepts a connection. |
protected abstract int |
available() |
Returns the number of bytes that can be read from this socket without blocking. |
protected abstract void |
bind |
Binds this socket to the specified local IP address and port number. |
protected abstract void |
close() |
Closes this socket. |
protected abstract void |
connect |
Connects this socket to the specified port on the named host. |
protected abstract void |
connect |
Connects this socket to the specified port number on the specified host. |
protected abstract void |
connect |
Connects this socket to the specified port number on the specified host. |
protected abstract void |
create |
Creates either a stream or a datagram socket. |
protected FileDescriptor |
getFileDescriptor() |
Returns the value of this socket's fd field. |
protected InetAddress |
getInetAddress() |
Returns the value of this socket's address field. |
protected abstract InputStream |
getInputStream() |
Returns an input stream for this socket. |
protected int |
getLocalPort() |
Returns the value of this socket's localport field. |
protected <T> T |
getOption |
Called to get a socket option. |
protected abstract OutputStream |
getOutputStream() |
Returns an output stream for this socket. |
protected int |
getPort() |
Returns the value of this socket's port field. |
protected abstract void |
listen |
Sets the maximum queue length for incoming connection indications (a request to connect) to the count argument. |
protected abstract void |
sendUrgentData |
Send one byte of urgent data on the socket. |
protected <T> void |
setOption |
Called to set a socket option. |
protected void |
setPerformancePreferences |
Sets performance preferences for this socket. |
protected void |
shutdownInput() |
Places the input stream for this socket at "end of stream". |
protected void |
shutdownOutput() |
Disables the output stream for this socket. |
protected Set |
supportedOptions() |
Returns a set of SocketOptions supported by this impl and by this impl's socket (Socket or ServerSocket) |
protected boolean |
supportsUrgentData() |
Returns whether or not this SocketImpl supports sending urgent data. |
String |
toString() |
Returns the address and port of this socket as a String . |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
getOption, setOption
protected FileDescriptor fd
protected InetAddress address
protected int port
protected int localport
public SocketImpl()
protected abstract void create(boolean stream) throws IOException
stream
- if true
, create a stream socket; otherwise, create a datagram socket.IOException
- if an I/O error occurs while creating the socket.protected abstract void connect(String host, int port) throws IOException
host
- the name of the remote host.port
- the port number.IOException
- if an I/O error occurs when connecting to the remote host.protected abstract void connect(InetAddress address, int port) throws IOException
address
- the IP address of the remote host.port
- the port number.IOException
- if an I/O error occurs when attempting a connection.protected abstract void connect(SocketAddress address, int timeout) throws IOException
address
- the Socket address of the remote host.timeout
- the timeout value, in milliseconds, or zero for no timeout.IOException
- if an I/O error occurs when attempting a connection.protected abstract void bind(InetAddress host, int port) throws IOException
host
- an IP address that belongs to a local interface.port
- the port number.IOException
- if an I/O error occurs when binding this socket.protected abstract void listen(int backlog) throws IOException
count
argument. If a connection indication arrives when the queue is full, the connection is refused.backlog
- the maximum length of the queue.IOException
- if an I/O error occurs when creating the queue.protected abstract void accept(SocketImpl s) throws IOException
s
- the accepted connection.IOException
- if an I/O error occurs when accepting the connection.protected abstract InputStream getInputStream() throws IOException
IOException
- if an I/O error occurs when creating the input stream.protected abstract OutputStream getOutputStream() throws IOException
IOException
- if an I/O error occurs when creating the output stream.protected abstract int available() throws IOException
IOException
- if an I/O error occurs when determining the number of bytes available.protected abstract void close() throws IOException
IOException
- if an I/O error occurs when closing this socket.protected void shutdownInput() throws IOException
available
method will return 0, and its read
methods will return -1
(end of stream).IOException
- if an I/O error occurs when shutting down this socket.protected void shutdownOutput() throws IOException
IOException
- if an I/O error occurs when shutting down this socket.protected FileDescriptor getFileDescriptor()
fd
field.fd
field.protected InetAddress getInetAddress()
address
field.address
field.protected int getPort()
port
field.port
field.protected boolean supportsUrgentData()
protected abstract void sendUrgentData(int data) throws IOException
data
- The byte of data to sendIOException
- if there is an error sending the data.protected int getLocalPort()
localport
field.localport
field.public String toString()
String
.protected void setPerformancePreferences(int connectionTime, int latency, int bandwidth)
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. Negative values represent a lower priority than positive values. 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)
. By default, this method does nothing, unless it is overridden in a sub-class.
connectionTime
- An int
expressing the relative importance of a short connection timelatency
- An int
expressing the relative importance of low latencybandwidth
- An int
expressing the relative importance of high bandwidthprotected <T> void setOption(SocketOption<T> name, T value) throws IOException
name
is not null, then throws
UnsupportedOperationException
. Subclasses should override this method with an appropriate implementation.T
- The type of the socket option valuename
- The socket optionvalue
- The value of the socket option. A value of null
may be valid for some options.UnsupportedOperationException
- if the SocketImpl does not support the optionIllegalArgumentException
- if the value is not valid for the optionIOException
- if an I/O error occurs, or if the socket is closedNullPointerException
- if name is null
protected <T> T getOption(SocketOption<T> name) throws IOException
name
is not null, then throws
UnsupportedOperationException
. Subclasses should override this method with an appropriate implementation.T
- The type of the socket option valuename
- The socket optionUnsupportedOperationException
- if the SocketImpl does not support the optionIOException
- if an I/O error occurs, or if the socket is closedNullPointerException
- if name is null
protected Set<SocketOption<?>> supportedOptions()
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/net/SocketImpl.html