Connects this channel's socket.

  Connects this channel's socket.

The channel's socket is configured so that it only receives datagrams from, and sends datagrams to, the given remote peer address. Once connected, datagrams may not be received from or sent to any other address. A datagram socket remains connected until it is explicitly disconnected or until it is closed.

This method performs exactly the same security checks as the connect method of the DatagramSocket class. That is, if a security manager has been installed then this method verifies that its checkAccept and checkConnect methods permit datagrams to be received from and sent to, respectively, the given remote address.

This method may be invoked at any time. It will not have any effect on read or write operations that are already in progress at the moment that it is invoked.

Returns: This datagram channel
Parameters:
- remote - The remote address to which this channel is to be connected
Throws:
- ClosedChannelException - If this channel is closed
- AsynchronousCloseException - If another thread closes this channel while the connect operation is in progress
- ClosedByInterruptException - If another thread interrupts the current thread while the connect operation is in progress, thereby closing the channel and setting the current thread's interrupt status
- SecurityException - If a security manager has been installed and it does not permit access to the given remote address
- IOException - If some other I/O error occurs

  Disconnects this channel's socket.

  Disconnects this channel's socket.

The channel's socket is configured so that it can receive datagrams from, and sends datagrams to, any remote address so long as the security manager, if installed, permits it.

This method may be invoked at any time. It will not have any effect on read or write operations that are already in progress at the moment that it is invoked.

If this channel's socket is not connected, or if the channel is closed, then invoking this method has no effect.

Returns: This datagram channel
Throws:
- IOException - If some other I/O error occurs

  Tells whether or not this channel's socket is connected.

  Tells whether or not this channel's socket is connected.

Returns: true if, and only if, this channel's socket is connected

  Opens a datagram channel.

  Opens a datagram channel.

The new channel is created by invoking the openDatagramChannel method of the system-wide default SelectorProvider object. The channel will not be connected.

Returns: A new datagram channel
Throws:
- IOException - If an I/O error occurs

  Reads a datagram from this channel.

  Reads a datagram from this channel.

This method may only be invoked if this channel's socket is connected, and it only accepts datagrams from the socket's peer. If there are more bytes in the datagram than remain in the given buffer then the remainder of the datagram is silently discarded. Otherwise this method behaves exactly as specified in the ReadableByteChannel interface.

Throws:
- NotYetConnectedException - If this channel's socket is not connected

  Reads a datagram from this channel.

  Reads a datagram from this channel.

This method may only be invoked if this channel's socket is connected, and it only accepts datagrams from the socket's peer. If there are more bytes in the datagram than remain in the given buffers then the remainder of the datagram is silently discarded. Otherwise this method behaves exactly as specified in the ScatteringByteChannel interface.

Throws:
- NotYetConnectedException - If this channel's socket is not connected

  Reads a datagram from this channel.

  Reads a datagram from this channel.

This method may only be invoked if this channel's socket is connected, and it only accepts datagrams from the socket's peer. If there are more bytes in the datagram than remain in the given buffers then the remainder of the datagram is silently discarded. Otherwise this method behaves exactly as specified in the ScatteringByteChannel interface.

Throws:
- NotYetConnectedException - If this channel's socket is not connected

  Receives a datagram via this channel.

  Receives a datagram via this channel.

If a datagram is immediately available, or if this channel is in blocking mode and one eventually becomes available, then the datagram is copied into the given byte buffer and its source address is returned. If this channel is in non-blocking mode and a datagram is not immediately available then this method immediately returns null.

The datagram is transferred into the given byte buffer starting at its current position, as if by a regular read operation. If there are fewer bytes remaining in the buffer than are required to hold the datagram then the remainder of the datagram is silently discarded.

This method performs exactly the same security checks as the receive method of the DatagramSocket class. That is, if the socket is not connected to a specific remote address and a security manager has been installed then for each datagram received this method verifies that the source's address and port number are permitted by the security manager's checkAccept method. The overhead of this security check can be avoided by first connecting the socket via the connect method.

This method may be invoked at any time. If another thread has already initiated a read operation upon this channel, however, then an invocation of this method will block until the first operation is complete.

Returns: The datagram's source address, or null if this channel is in non-blocking mode and no datagram was immediately available
Parameters:
- dst - The buffer into which the datagram is to be transferred
Throws:
- ClosedChannelException - If this channel is closed
- AsynchronousCloseException - If another thread closes this channel while the read operation is in progress
- ClosedByInterruptException - If another thread interrupts the current thread while the read operation is in progress, thereby closing the channel and setting the current thread's interrupt status
- SecurityException - If a security manager has been installed and it does not permit datagrams to be accepted from the datagram's sender
- IOException - If some other I/O error occurs

  Sends a datagram via this channel.

  Sends a datagram via this channel.

If this channel is in non-blocking mode and there is sufficient room in the underlying output buffer, or if this channel is in blocking mode and sufficient room becomes available, then the remaining bytes in the given buffer are transmitted as a single datagram to the given target address.

The datagram is transferred from the byte buffer as if by a regular write operation.

This method performs exactly the same security checks as the send method of the DatagramSocket class. That is, if the socket is not connected to a specific remote address and a security manager has been installed then for each datagram sent this method verifies that the target address and port number are permitted by the security manager's checkConnect method. The overhead of this security check can be avoided by first connecting the socket via the connect method.

This method may be invoked at any time. If another thread has already initiated a write operation upon this channel, however, then an invocation of this method will block until the first operation is complete.

Returns: The number of bytes sent, which will be either the number of bytes that were remaining in the source buffer when this method was invoked or, if this channel is non-blocking, may be zero if there was insufficient room for the datagram in the underlying output buffer
Parameters:
- src - The buffer containing the datagram to be sent
- target - The address to which the datagram is to be sent
Throws:
- ClosedChannelException - If this channel is closed
- AsynchronousCloseException - If another thread closes this channel while the read operation is in progress
- ClosedByInterruptException - If another thread interrupts the current thread while the read operation is in progress, thereby closing the channel and setting the current thread's interrupt status
- SecurityException - If a security manager has been installed and it does not permit datagrams to be sent to the given address
- IOException - If some other I/O error occurs

  Retrieves a datagram socket associated with this channel.

  Retrieves a datagram socket associated with this channel.

The returned object will not declare any public methods that are not declared in the DatagramSocket class.

Returns: A datagram socket associated with this channel

  Returns an operation set identifying this channel's supported operations.

  Returns an operation set identifying this channel's supported operations.

Datagram channels support reading and writing, so this method returns (SelectionKey.OP_READ | SelectionKey.OP_WRITE).

Returns: The valid-operation set

  Writes a datagram to this channel.

  Writes a datagram to this channel.

This method may only be invoked if this channel's socket is connected, in which case it sends datagrams directly to the socket's peer. Otherwise it behaves exactly as specified in the WritableByteChannel interface.

Throws:
- NotYetConnectedException - If this channel's socket is not connected

  Writes a datagram to this channel.

  Writes a datagram to this channel.

This method may only be invoked if this channel's socket is connected, in which case it sends datagrams directly to the socket's peer. Otherwise it behaves exactly as specified in the GatheringByteChannel interface.

Returns: The number of bytes sent, which will be either the number of bytes that were remaining in the source buffer when this method was invoked or, if this channel is non-blocking, may be zero if there was insufficient room for the datagram in the underlying output buffer
Throws:
- NotYetConnectedException - If this channel's socket is not connected

  Writes a datagram to this channel.

  Writes a datagram to this channel.

This method may only be invoked if this channel's socket is connected, in which case it sends datagrams directly to the socket's peer. Otherwise it behaves exactly as specified in the GatheringByteChannel interface.

Returns: The number of bytes sent, which will be either the number of bytes that were remaining in the source buffer when this method was invoked or, if this channel is non-blocking, may be zero if there was insufficient room for the datagram in the underlying output buffer
Throws:
- NotYetConnectedException - If this channel's socket is not connected