- All Implemented Interfaces:
Closeable
,AutoCloseable
- Direct Known Subclasses:
MulticastSocket
public class DatagramSocket extends Object implements Closeable
A datagram socket is the sending or receiving point for a packet delivery service. Each packet sent or received on a datagram socket is individually addressed and routed. Multiple packets sent from one machine to another may be routed differently, and may arrive in any order.
Where possible, a newly constructed DatagramSocket
has the
SO_BROADCAST
socket option enabled so as
to allow the transmission of broadcast datagrams. In order to receive
broadcast packets a DatagramSocket should be bound to the wildcard address.
In some implementations, broadcast packets may also be received when
a DatagramSocket is bound to a more specific address.
Example:
DatagramSocket s = new DatagramSocket(null);
s.bind(new InetSocketAddress(8888));
Which is equivalent to:
DatagramSocket s = new DatagramSocket(8888);
Both cases will create a DatagramSocket able to receive broadcasts on
UDP port 8888.
The DatagramSocket
class defines convenience
methods to set and get several socket options. This class also
defines the setOption
and getOption
methods to set
and query socket options.
A DatagramSocket
supports the following socket options:
An implementation may also support additional options. In particular an implementation may support multicast options which can be useful when using a plain
Option Name Description SO_SNDBUF
The size of the socket send buffer SO_RCVBUF
The size of the socket receive buffer SO_REUSEADDR
Re-use address SO_BROADCAST
Allow transmission of broadcast datagrams IP_TOS
The Type of Service (ToS) octet in the Internet Protocol (IP) header
DatagramSocket
to send datagrams to a
multicast group.- Since:
- 1.0
- See Also:
DatagramPacket
,DatagramChannel
-
Constructor Summary
ModifierConstructorDescriptionConstructs a datagram socket and binds it to any available port on the local host machine.DatagramSocket(int port)
Constructs a datagram socket and binds it to the specified port on the local host machine.DatagramSocket(int port, InetAddress laddr)
Creates a datagram socket, bound to the specified local address.protected
DatagramSocket(DatagramSocketImpl impl)
Creates an unbound datagram socket with the specified DatagramSocketImpl.DatagramSocket(SocketAddress bindaddr)
Creates a datagram socket, bound to the specified local socket address. -
Method Summary
Modifier and TypeMethodDescriptionvoid
bind(SocketAddress addr)
Binds this DatagramSocket to a specific address and port.void
close()
Closes this datagram socket.void
connect(InetAddress address, int port)
Connects the socket to a remote address for this socket.void
connect(SocketAddress addr)
Connects this socket to a remote socket address (IP address + port number).void
Disconnects the socket.boolean
Tests if SO_BROADCAST is enabled.Returns the uniqueDatagramChannel
object associated with this datagram socket, if any.Returns the address to which this socket is connected.Gets the local address to which the socket is bound.int
Returns the port number on the local host to which this socket is bound.Returns the address of the endpoint this socket is bound to.<T> T
getOption(SocketOption<T> name)
Returns the value of a socket option.int
getPort()
Returns the port number to which this socket is connected.int
Get value of the SO_RCVBUF option for thisDatagramSocket
, that is the buffer size used by the platform for input on thisDatagramSocket
.Returns the address of the endpoint this socket is connected to, ornull
if it is unconnected.boolean
Tests if SO_REUSEADDR is enabled.int
Get value of the SO_SNDBUF option for thisDatagramSocket
, that is the buffer size used by the platform for output on thisDatagramSocket
.int
Retrieve setting for SO_TIMEOUT. 0 returns implies that the option is disabled (i.e., timeout of infinity).int
Gets traffic class or type-of-service in the IP datagram header for packets sent from this DatagramSocket.boolean
isBound()
Returns the binding state of the socket.boolean
isClosed()
Returns whether the socket is closed or not.boolean
Returns the connection state of the socket.void
Receives a datagram packet from this socket.void
send(DatagramPacket p)
Sends a datagram packet from this socket.void
setBroadcast(boolean on)
Enable/disable SO_BROADCAST.static void
Sets the datagram socket implementation factory for the application.<T> DatagramSocket
setOption(SocketOption<T> name, T value)
Sets the value of a socket option.void
setReceiveBufferSize(int size)
Sets the SO_RCVBUF option to the specified value for thisDatagramSocket
.void
setReuseAddress(boolean on)
Enable/disable the SO_REUSEADDR socket option.void
setSendBufferSize(int size)
Sets the SO_SNDBUF option to the specified value for thisDatagramSocket
.void
setSoTimeout(int timeout)
Enable/disable SO_TIMEOUT with the specified timeout, in milliseconds.void
setTrafficClass(int tc)
Sets traffic class or type-of-service octet in the IP datagram header for datagrams sent from this DatagramSocket.Set<SocketOption<?>>
Returns a set of the socket options supported by this socket.
-
Constructor Details
-
DatagramSocket
Constructs a datagram socket and binds it to any available port on the local host machine. The socket will be bound to thewildcard
address.If there is a security manager, its
checkListen
method is first called with 0 as its argument to ensure the operation is allowed. This could result in a SecurityException.- Throws:
SocketException
- if the socket could not be opened, or the socket could not be bound.SecurityException
- if a security manager exists and itscheckListen
method doesn't allow the operation.- See Also:
SecurityManager.checkListen(int)
-
DatagramSocket
Creates an unbound datagram socket with the specified DatagramSocketImpl.- Parameters:
impl
- an instance of a DatagramSocketImpl the subclass wishes to use on the DatagramSocket.- Since:
- 1.4
-
DatagramSocket
Creates a datagram socket, bound to the specified local socket address.If the address is
null
an unbound socket will be created.If there is a security manager, its
checkListen
method is first called with the port from the socket address as its argument to ensure the operation is allowed. This could result in a SecurityException.- Parameters:
bindaddr
- local socket address to bind, ornull
for an unbound socket.- Throws:
SocketException
- if the socket could not be opened, or the socket could not bind to the specified local port.SecurityException
- if a security manager exists and itscheckListen
method doesn't allow the operation.IllegalArgumentException
- if bindaddr is a SocketAddress subclass not supported by this socket.- Since:
- 1.4
- See Also:
SecurityManager.checkListen(int)
-
DatagramSocket
Constructs a datagram socket and binds it to the specified port on the local host machine. The socket will be bound to thewildcard
address.If there is a security manager, its
checkListen
method is first called with theport
argument as its argument to ensure the operation is allowed. This could result in a SecurityException.- Parameters:
port
- local port to use in the bind operation.- Throws:
SocketException
- if the socket could not be opened, or the socket could not bind to the specified local port.SecurityException
- if a security manager exists and itscheckListen
method doesn't allow the operation.IllegalArgumentException
- if port is out of range.- See Also:
SecurityManager.checkListen(int)
-
DatagramSocket
Creates a datagram socket, bound to the specified local address.The local port must be between 0 and 65535 inclusive. A port number of
zero
will let the system pick up an ephemeral port in abind
operation.If the IP address is a
wildcard
address, or isnull
, the socket will be bound to the wildcard address.If there is a security manager, its
checkListen
method is first called with theport
argument as its argument to ensure the operation is allowed. This could result in a SecurityException.- Parameters:
port
- local port to use in the bind operation.laddr
- local address to bind (can benull
)- Throws:
SocketException
- if the socket could not be opened, or the socket could not bind to the specified local port.SecurityException
- if a security manager exists and itscheckListen
method doesn't allow the operation.IllegalArgumentException
- if port is out of range.- Since:
- 1.1
- See Also:
SecurityManager.checkListen(int)
-
-
Method Details
-
bind
Binds this DatagramSocket to a specific address and port.If the address is
null
, then the system will pick up an ephemeral port and a valid local address to bind the socket.- Parameters:
addr
- The address and port to bind to.- Throws:
SocketException
- if any error happens during the bind, or if the socket is already bound.SecurityException
- if a security manager exists and itscheckListen
method doesn't allow the operation.IllegalArgumentException
- if addr is a SocketAddress subclass not supported by this socket.- Since:
- 1.4
-
connect
Connects the socket to a remote address for this socket. When a socket is connected to a remote address, packets may only be sent to or received from that address. By default a datagram socket is not connected. If the socket is already closed, then this method has no effect.If this socket is not bound then this method will first cause the socket to be bound to an address that is assigned automatically, as if invoking the
bind
method with a parameter ofnull
. If the remote destination to which the socket is connected does not exist, or is otherwise unreachable, and if an ICMP destination unreachable packet has been received for that address, then a subsequent call to send or receive may throw a PortUnreachableException. Note, there is no guarantee that the exception will be thrown.If a security manager has been installed then it is invoked to check access to the remote address. Specifically, if the given
address
is amulticast address
, the security manager'scheckMulticast
method is invoked with the givenaddress
. Otherwise, the security manager'scheckConnect
andcheckAccept
methods are invoked, with the givenaddress
andport
, to verify that datagrams are permitted to be sent and received respectively.Care should be taken to ensure that a connected datagram socket is not shared with untrusted code. When a socket is connected,
receive
andsend
will not perform any security checks on incoming and outgoing packets, other than matching the packet's and the socket's address and port. On a send operation, if the packet's address is set and the packet's address and the socket's address do not match, anIllegalArgumentException
will be thrown. A socket connected to a multicast address may only be used to send packets. Datagrams in the socket's socket receive buffer, which have not been received before invoking this method, may be discarded.- Parameters:
address
- the remote address for the socketport
- the remote port for the socket.- Throws:
IllegalArgumentException
- if the address is null, or the port is out of range.SecurityException
- if a security manager has been installed and it does not permit access to the given remote addressUncheckedIOException
- may be thrown if connect fails, for example, if the destination address is non-routable- Since:
- 1.2
- See Also:
disconnect()
-
connect
Connects this socket to a remote socket address (IP address + port number).If given an
InetSocketAddress
, this method behaves as if invokingconnect(InetAddress,int)
with the given socket addresses IP address and port number, except that theSocketException
that may be raised is not wrapped in anUncheckedIOException
. Datagrams in the socket's socket receive buffer, which have not been received before invoking this method, may be discarded.- Parameters:
addr
- The remote address.- Throws:
SocketException
- if the connect failsIllegalArgumentException
- ifaddr
isnull
, oraddr
is a SocketAddress subclass not supported by this socketSecurityException
- if a security manager has been installed and it does not permit access to the given remote address- Since:
- 1.4
-
disconnect
public void disconnect()Disconnects the socket. If the socket is closed or not connected, then this method has no effect.- API Note:
- If this method throws an UncheckedIOException, the socket may be left in an unspecified state. It is strongly recommended that the socket be closed when disconnect fails.
- Throws:
UncheckedIOException
- may be thrown if disconnect fails to dissolve the association and restore the socket to a consistent state.- Since:
- 1.2
- See Also:
connect(java.net.InetAddress, int)
-
isBound
public boolean isBound()Returns the binding state of the socket.If the socket was bound prior to being
closed
, then this method will continue to returntrue
after the socket is closed.- Returns:
- true if the socket successfully bound to an address
- Since:
- 1.4
-
isConnected
public boolean isConnected()Returns the connection state of the socket.If the socket was connected prior to being
closed
, then this method will continue to returntrue
after the socket is closed.- Returns:
- true if the socket successfully connected to a server
- Since:
- 1.4
-
getInetAddress
Returns the address to which this socket is connected. Returnsnull
if the socket is not connected.If the socket was connected prior to being
closed
, then this method will continue to return the connected address after the socket is closed.- Returns:
- the address to which this socket is connected.
- Since:
- 1.2
-
getPort
public int getPort()Returns the port number to which this socket is connected. Returns-1
if the socket is not connected.If the socket was connected prior to being
closed
, then this method will continue to return the connected port number after the socket is closed.- Returns:
- the port number to which this socket is connected.
- Since:
- 1.2
-
getRemoteSocketAddress
Returns the address of the endpoint this socket is connected to, ornull
if it is unconnected.If the socket was connected prior to being
closed
, then this method will continue to return the connected address after the socket is closed.- Returns:
- a
SocketAddress
representing the remote endpoint of this socket, ornull
if it is not connected yet. - Since:
- 1.4
- See Also:
getInetAddress()
,getPort()
,connect(SocketAddress)
-
getLocalSocketAddress
Returns the address of the endpoint this socket is bound to.- Returns:
- a
SocketAddress
representing the local endpoint of this socket, ornull
if it is closed or not bound yet. - Since:
- 1.4
- See Also:
getLocalAddress()
,getLocalPort()
,bind(SocketAddress)
-
send
Sends a datagram packet from this socket. TheDatagramPacket
includes information indicating the data to be sent, its length, the IP address of the remote host, and the port number on the remote host.If there is a security manager, and the socket is not currently connected to a remote address, this method first performs some security checks. First, if
p.getAddress().isMulticastAddress()
is true, this method calls the security manager'scheckMulticast
method withp.getAddress()
as its argument. If the evaluation of that expression is false, this method instead calls the security manager'scheckConnect
method with argumentsp.getAddress().getHostAddress()
andp.getPort()
. Each call to a security manager method could result in a SecurityException if the operation is not allowed.- Parameters:
p
- theDatagramPacket
to be sent.- Throws:
IOException
- if an I/O error occurs.SecurityException
- if a security manager exists and itscheckMulticast
orcheckConnect
method doesn't allow the send.PortUnreachableException
- may be thrown if the socket is connected to a currently unreachable destination. Note, there is no guarantee that the exception will be thrown.IllegalBlockingModeException
- if this socket has an associated channel, and the channel is in non-blocking mode.IllegalArgumentException
- if the socket is connected, and connected address and packet address differ, or if the socket is not connected and the packet address is not set or if its port is out of range.- See Also:
DatagramPacket
,SecurityManager.checkMulticast(InetAddress)
,SecurityManager.checkConnect(java.lang.String, int)
-
receive
Receives a datagram packet from this socket. When this method returns, theDatagramPacket
's buffer is filled with the data received. The datagram packet also contains the sender's IP address, and the port number on the sender's machine.This method blocks until a datagram is received. The
length
field of the datagram packet object contains the length of the received message. If the message is longer than the packet's length, the message is truncated.If there is a security manager, and the socket is not currently connected to a remote address, a packet cannot be received if the security manager's
checkAccept
method does not allow it. Datagrams that are not permitted by the security manager are silently discarded.- Parameters:
p
- theDatagramPacket
into which to place the incoming data.- Throws:
IOException
- if an I/O error occurs.SocketTimeoutException
- if setSoTimeout was previously called and the timeout has expired.PortUnreachableException
- may be thrown if the socket is connected to a currently unreachable destination. Note, there is no guarantee that the exception will be thrown.IllegalBlockingModeException
- if this socket has an associated channel, and the channel is in non-blocking mode.- See Also:
DatagramPacket
,DatagramSocket
-
getLocalAddress
Gets the local address to which the socket is bound.If there is a security manager, its
checkConnect
method is first called with the host address and-1
as its arguments to see if the operation is allowed.- Returns:
- the local address to which the socket is bound,
null
if the socket is closed, or anInetAddress
representingwildcard
address if either the socket is not bound, or the security managercheckConnect
method does not allow the operation - Since:
- 1.1
- See Also:
SecurityManager.checkConnect(java.lang.String, int)
-
getLocalPort
public int getLocalPort()Returns the port number on the local host to which this socket is bound.- Returns:
- the port number on the local host to which this socket is bound,
-1
if the socket is closed, or0
if it is not bound yet.
-
setSoTimeout
Enable/disable SO_TIMEOUT with the specified timeout, in milliseconds. With this option set to a positive timeout value, a call to receive() for this DatagramSocket will block for only this amount of time. If the timeout expires, a java.net.SocketTimeoutException is raised, though the DatagramSocket is still valid. A timeout of zero is interpreted as an infinite timeout. The option must be enabled prior to entering the blocking operation to have effect.- Parameters:
timeout
- the specified timeout in milliseconds.- Throws:
SocketException
- if there is an error in the underlying protocol, such as an UDP error.IllegalArgumentException
- iftimeout
is negative- Since:
- 1.1
- See Also:
getSoTimeout()
-
getSoTimeout
Retrieve setting for SO_TIMEOUT. 0 returns implies that the option is disabled (i.e., timeout of infinity).- Returns:
- the setting for SO_TIMEOUT
- Throws:
SocketException
- if there is an error in the underlying protocol, such as an UDP error.- Since:
- 1.1
- See Also:
setSoTimeout(int)
-
setSendBufferSize
Sets the SO_SNDBUF option to the specified value for thisDatagramSocket
. The SO_SNDBUF option is used by the network implementation as a hint to size the underlying network I/O buffers. The SO_SNDBUF setting may also be used by the network implementation to determine the maximum size of the packet that can be sent on this socket.As SO_SNDBUF is a hint, applications that want to verify what size the buffer is should call
getSendBufferSize()
.Increasing the buffer size may allow multiple outgoing packets to be queued by the network implementation when the send rate is high.
Note: If
send(DatagramPacket)
is used to send aDatagramPacket
that is larger than the setting of SO_SNDBUF then it is implementation specific if the packet is sent or discarded.- Parameters:
size
- the size to which to set the send buffer size. This value must be greater than 0.- Throws:
SocketException
- if there is an error in the underlying protocol, such as an UDP error.IllegalArgumentException
- if the value is 0 or is negative.- Since:
- 1.2
- See Also:
getSendBufferSize()
-
getSendBufferSize
Get value of the SO_SNDBUF option for thisDatagramSocket
, that is the buffer size used by the platform for output on thisDatagramSocket
.- Returns:
- the value of the SO_SNDBUF option for this
DatagramSocket
- Throws:
SocketException
- if there is an error in the underlying protocol, such as an UDP error.- Since:
- 1.2
- See Also:
setSendBufferSize(int)
-
setReceiveBufferSize
Sets the SO_RCVBUF option to the specified value for thisDatagramSocket
. The SO_RCVBUF option is used by the network implementation as a hint to size the underlying network I/O buffers. The SO_RCVBUF setting may also be used by the network implementation to determine the maximum size of the packet that can be received on this socket.Because SO_RCVBUF is a hint, applications that want to verify what size the buffers were set to should call
getReceiveBufferSize()
.Increasing SO_RCVBUF may allow the network implementation to buffer multiple packets when packets arrive faster than are being received using
receive(DatagramPacket)
.Note: It is implementation specific if a packet larger than SO_RCVBUF can be received.
- 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 an UDP error.IllegalArgumentException
- if the value is 0 or is negative.- Since:
- 1.2
- See Also:
getReceiveBufferSize()
-
getReceiveBufferSize
Get value of the SO_RCVBUF option for thisDatagramSocket
, that is the buffer size used by the platform for input on thisDatagramSocket
.- Returns:
- the value of the SO_RCVBUF option for this
DatagramSocket
- Throws:
SocketException
- if there is an error in the underlying protocol, such as an UDP error.- Since:
- 1.2
- See Also:
setReceiveBufferSize(int)
-
setReuseAddress
Enable/disable the SO_REUSEADDR socket option.For UDP sockets it may be necessary to bind more than one socket to the same socket address. This is typically for the purpose of receiving multicast packets (See
MulticastSocket
). TheSO_REUSEADDR
socket option allows multiple sockets to be bound to the same socket address if theSO_REUSEADDR
socket option is enabled prior to binding the socket usingbind(SocketAddress)
.Note: This functionality is not supported by all existing platforms, so it is implementation specific whether this option will be ignored or not. However, if it is not supported then
getReuseAddress()
will always returnfalse
.When a
DatagramSocket
is created the initial setting ofSO_REUSEADDR
is disabled.The behaviour when
SO_REUSEADDR
is enabled or disabled after a socket is bound (SeeisBound()
) is not defined.- Parameters:
on
- whether to enable or disable the- Throws:
SocketException
- if an error occurs enabling or disabling theSO_REUSEADDR
socket option, or the socket is closed.- Since:
- 1.4
- See Also:
getReuseAddress()
,bind(SocketAddress)
,isBound()
,isClosed()
-
getReuseAddress
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 an UDP error.- Since:
- 1.4
- See Also:
setReuseAddress(boolean)
-
setBroadcast
Enable/disable SO_BROADCAST.Some operating systems may require that the Java virtual machine be started with implementation specific privileges to enable this option or send broadcast datagrams.
- Parameters:
on
- whether or not to have broadcast turned on.- Throws:
SocketException
- if there is an error in the underlying protocol, such as an UDP error.- Since:
- 1.4
- See Also:
getBroadcast()
-
getBroadcast
Tests if SO_BROADCAST is enabled.- Returns:
- a
boolean
indicating whether or not SO_BROADCAST is enabled. - Throws:
SocketException
- if there is an error in the underlying protocol, such as an UDP error.- Since:
- 1.4
- See Also:
setBroadcast(boolean)
-
setTrafficClass
Sets traffic class or type-of-service octet in the IP datagram header for datagrams sent from this DatagramSocket. 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
integer
, the least significant 8 bits of which represent the value of the TOS octet in IP packets sent by the socket. RFC 1349 defines the TOS values as follows:IPTOS_LOWCOST (0x02)
IPTOS_RELIABILITY (0x04)
IPTOS_THROUGHPUT (0x08)
IPTOS_LOWDELAY (0x10)
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.- Parameters:
tc
- anint
value for the bitset.- Throws:
SocketException
- if there is an error setting the traffic class or type-of-service- Since:
- 1.4
- See Also:
getTrafficClass()
-
getTrafficClass
Gets traffic class or type-of-service in the IP datagram header for packets sent from this DatagramSocket.As the underlying network implementation may ignore the traffic class or type-of-service set using
setTrafficClass(int)
this method may return a different value than was previously set using thesetTrafficClass(int)
method on this DatagramSocket.- Returns:
- 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 Also:
setTrafficClass(int)
-
close
public void close()Closes this datagram socket.Any thread currently blocked in
receive(java.net.DatagramPacket)
upon this socket will throw aSocketException
.If this socket has an associated channel then the channel is closed as well.
- Specified by:
close
in interfaceAutoCloseable
- Specified by:
close
in interfaceCloseable
-
isClosed
public boolean isClosed()Returns whether the socket is closed or not.- Returns:
- true if the socket has been closed
- Since:
- 1.4
-
getChannel
Returns the uniqueDatagramChannel
object associated with this datagram socket, if any.A datagram socket will have a channel if, and only if, the channel itself was created via the
DatagramChannel.open
method.- Returns:
- the datagram channel associated with this datagram socket,
or
null
if this socket was not created for a channel - Since:
- 1.4
-
setDatagramSocketImplFactory
Sets the datagram socket implementation factory for the application. The factory can be specified only once.When an application creates a new datagram socket, the socket implementation factory's
createDatagramSocketImpl
method is called to create the actual datagram 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 datagram socket factory.SocketException
- if the factory is already defined.SecurityException
- if a security manager exists and itscheckSetFactory
method doesn't allow the operation.- Since:
- 1.3
- See Also:
DatagramSocketImplFactory.createDatagramSocketImpl()
,SecurityManager.checkSetFactory()
-
setOption
Sets the value of a socket option.- Type Parameters:
T
- The type of the socket option value- Parameters:
name
- The socket optionvalue
- The value of the socket option. A value ofnull
may be valid for some options.- Returns:
- this DatagramSocket
- Throws:
UnsupportedOperationException
- if the datagram socket does not support the option.IllegalArgumentException
- if the value is not valid for the option.IOException
- if an I/O error occurs, or if the socket is closed.SecurityException
- if a security manager is set and if the socket option requires a security permission and if the caller does not have the required permission.StandardSocketOptions
do not require any security permission.NullPointerException
- if name isnull
- Since:
- 9
-
getOption
Returns the value of a socket option.- Type Parameters:
T
- The type of the socket option value- Parameters:
name
- The socket option- Returns:
- The value of the socket option.
- Throws:
UnsupportedOperationException
- if the datagram socket does not support the option.IOException
- if an I/O error occurs, or if the socket is closed.NullPointerException
- if name isnull
SecurityException
- if a security manager is set and if the socket option requires a security permission and if the caller does not have the required permission.StandardSocketOptions
do not require any security permission.- Since:
- 9
-
supportedOptions
Returns a set of the socket options supported by this socket. This method will continue to return the set of options even after the socket has been closed.- Returns:
- A set of the socket options supported by this socket. This set may be empty if the socket's DatagramSocketImpl cannot be created.
- Since:
- 9
-