Class DatagramSocket

public DatagramSocket()
            throws SocketException

Initializes a new instance of DatagramSocket that binds to a random port and every address on the local machine.

Throws:

SocketException - If an error occurs.

SecurityException - If a security manager exists and its checkListen method doesn't allow the operation.

public DatagramSocket(int port)
            throws SocketException

Initializes a new instance of DatagramSocket that binds to the specified port and every address on the local machine.

Parameters:

port - The local port number to bind to.

Throws:

SecurityException - If a security manager exists and its checkListen method doesn't allow the operation.

SocketException - If an error occurs.

public DatagramSocket(int port,
                      InetAddress addr)
            throws SocketException

Initializes a new instance of DatagramSocket that binds to the specified local port and address.

Parameters:

port - The local port number to bind to.

addr - The local address to bind to.

Throws:

SecurityException - If a security manager exists and its checkListen method doesn't allow the operation.

SocketException - If an error occurs.

protected DatagramSocket(DatagramSocketImpl impl)

Creates a DatagramSocket from a specified DatagramSocketImpl instance

Parameters:

impl - The DatagramSocketImpl the socket will be created from

Since:

1.4

public DatagramSocket(SocketAddress address)
            throws SocketException

Initializes a new instance of DatagramSocket that binds to the specified local port and address.

Parameters:

address - The local address and port number to bind to.

Throws:

SecurityException - If a security manager exists and its checkListen method doesn't allow the operation.

SocketException - If an error occurs.

Since:

1.4

public void bind(SocketAddress address)
            throws SocketException

Binds the socket to the given socket address.

Parameters:

address - The socket address to bind to.

Throws:

SocketException - If an error occurs.

SecurityException - If a security manager exists and its checkListen method doesn't allow the operation.

IllegalArgumentException - If address type is not supported.

Since:

1.4

public void close()

Closes this datagram socket.

public void connect(InetAddress address,
                    int port)

This method connects this socket to the specified address and port. When a datagram socket is connected, it will only send or receive packets to and from the host to which it is connected. A multicast socket that is connected may only send and not receive packets.

Parameters:

address - The address to connect this socket to.

port - The port to connect this socket to.

Throws:

IllegalArgumentException - If address or port are invalid.

SecurityException - If the caller is not allowed to send datagrams to or receive from this address and port.

Since:

1.2

public void connect(SocketAddress address)
            throws SocketException

Connects the datagram socket to a specified socket address.

Parameters:

address - The socket address to connect to.

Throws:

SocketException - If an error occurs.

IllegalArgumentException - If address type is not supported.

Since:

1.4

public void disconnect()

This method disconnects this socket from the address/port it was connected to. If the socket was not connected in the first place, this method does nothing.

Since:

1.2

public boolean getBroadcast()
            throws SocketException

Checks if SO_BROADCAST is enabled

Returns:

Whether SO_BROADCAST is set

Throws:

SocketException - If an error occurs

Since:

1.4

public DatagramChannel getChannel()

Returns the datagram channel assoziated with this datagram socket.

Returns:

The associated DatagramChannel object or null

Since:

1.4

public InetAddress getInetAddress()

This method returns the remote address to which this socket is connected. If this socket is not connected, then this method will return null.

Returns:

The remote address.

Since:

1.2

public InetAddress getLocalAddress()

Returns the local address this datagram socket is bound to.

Returns:

The local address is the socket is bound or null

Since:

1.1

public int getLocalPort()

Returns the local port this socket is bound to.

Returns:

The local port number.

public SocketAddress getLocalSocketAddress()

Returns the local SocketAddress this socket is bound to.

Returns:

The local SocketAddress or null if the socket is not bound.

Since:

1.4

public int getPort()

This method returns the remote port to which this socket is connected. If this socket is not connected, then this method will return -1.

Returns:

The remote port.

Since:

1.2

public int getReceiveBufferSize()
            throws SocketException

This method returns the value of the system level socket option SO_RCVBUF, which is used by the operating system to tune buffer sizes for data transfers.

Returns:

The receive buffer size.

Throws:

SocketException - If an error occurs.

Since:

1.2

public SocketAddress getRemoteSocketAddress()

Returns the SocketAddress of the host this socket is conneted to or null if this socket is not connected.

Returns:

The socket address of the remote host if connected or null

Since:

1.4

public boolean getReuseAddress()
            throws SocketException

Checks if SO_REUSEADDR is enabled.

Returns:

True if SO_REUSEADDR is set on the socket, false otherwise.

Throws:

SocketException - If an error occurs.

Since:

1.4

public int getSendBufferSize()
            throws SocketException

This method returns the value of the system level socket option SO_SNDBUF, which is used by the operating system to tune buffer sizes for data transfers.

Returns:

The send buffer size.

Throws:

SocketException - If an error occurs.

Since:

1.2

public int getSoTimeout()
            throws SocketException

Returns the value of the socket's SO_TIMEOUT setting. If this method returns 0 then SO_TIMEOUT is disabled.

Returns:

The current timeout in milliseconds.

Throws:

SocketException - If an error occurs.

Since:

1.1

public int getTrafficClass()
            throws SocketException

Returns the current traffic class

Returns:

The current traffic class.

Throws:

SocketException - If an error occurs

Since:

1.4

See Also:

DatagramSocket.setTrafficClass(int tc)

public boolean isBound()

Returns the binding state of the socket.

Returns:

True if socket bound, false otherwise.

Since:

1.4

public boolean isClosed()

Checks if the datagram socket is closed.

Returns:

True if socket is closed, false otherwise.

Since:

1.4

public boolean isConnected()

Returns the connection state of the socket.

Returns:

True if socket is connected, false otherwise.

Since:

1.4

public void receive(DatagramPacket p)
            throws IOException

Reads a datagram packet from the socket. Note that this method will block until a packet is received from the network. On return, the passed in DatagramPacket is populated with the data received and all the other information about the packet.

Parameters:

p - A DatagramPacket for storing the data

Throws:

IOException - If an error occurs.

IllegalBlockingModeException - If this socket has an associated channel, and the channel is in non-blocking mode.

SecurityException - If a security manager exists and its checkAccept method doesn't allow the receive.

public void send(DatagramPacket p)
            throws IOException

Sends the specified packet. The host and port to which the packet are to be sent should be set inside the packet.

Parameters:

p - The datagram packet to send.

Throws:

IOException - If an error occurs.

SecurityException - If a security manager exists and its checkMulticast or checkConnect method doesn't allow the send.

IllegalBlockingModeException - If this socket has an associated channel, and the channel is in non-blocking mode.

public void setBroadcast(boolean enable)
            throws SocketException

Enables/Disables SO_BROADCAST

Parameters:

enable - True if SO_BROADCAST should be enabled, false otherwise.

Throws:

SocketException - If an error occurs

Since:

1.4

public static void setDatagramSocketImplFactory(DatagramSocketImplFactory fac)
            throws IOException

Sets the datagram socket implementation factory for the application

Parameters:

fac - The factory to set

Throws:

IOException - If an error occurs

SecurityException - If a security manager exists and its checkSetFactory method doesn't allow the operation

public void setReceiveBufferSize(int size)
            throws SocketException

This method sets the value for the system level socket option SO_RCVBUF to the specified value. Note that valid values for this option are specific to a given operating system.

Parameters:

size - The new receive buffer size.

Throws:

SocketException - If an error occurs.

IllegalArgumentException - If size is 0 or negative.

Since:

1.2

public void setReuseAddress(boolean on)
            throws SocketException

Enables/Disables SO_REUSEADDR.

Parameters:

on - Whether or not to have SO_REUSEADDR turned on.

Throws:

SocketException - If an error occurs.

Since:

1.4

public void setSendBufferSize(int size)
            throws SocketException

This method sets the value for the system level socket option SO_SNDBUF to the specified value. Note that valid values for this option are specific to a given operating system.

Parameters:

size - The new send buffer size.

Throws:

SocketException - If an error occurs.

IllegalArgumentException - If size is 0 or negative.

Since:

1.2

public void setSoTimeout(int timeout)
            throws SocketException

Sets the value of the socket's SO_TIMEOUT value. A value of 0 will disable SO_TIMEOUT. Any other value is the number of milliseconds a socket read/write will block before timing out.

Parameters:

timeout - The new SO_TIMEOUT value in milliseconds.

Throws:

SocketException - If an error occurs.

Since:

1.1

public void setTrafficClass(int tc)
            throws SocketException

Sets the traffic class value

Parameters:

tc - The traffic class

Throws:

SocketException - If an error occurs

IllegalArgumentException - If tc value is illegal

Since:

1.4

See Also:

getTrafficClass()