/**@class java.nio.channels.DatagramChannel implements java.nio.channels.ByteChannel implements java.nio.channels.ScatteringByteChannel implements java.nio.channels.GatheringByteChannel implements java.nio.channels.MulticastChannel @extends java.nio.channels.spi.AbstractSelectableChannel A selectable channel for datagram-oriented sockets. <p> A datagram channel is created by invoking one of the {@link #open open} methods of this class. It is not possible to create a channel for an arbitrary, pre-existing datagram socket. A newly-created datagram channel is open but not connected. A datagram channel need not be connected in order for the {@link #send send} and {@link #receive receive} methods to be used. A datagram channel may be connected, by invoking its {@link #connect connect} method, in order to avoid the overhead of the security checks are otherwise performed as part of every send and receive operation. A datagram channel must be connected in order to use the {@link #read(java.nio.ByteBuffer) read} and {@link #write(java.nio.ByteBuffer) write} methods, since those methods do not accept or return socket addresses. <p> Once connected, a datagram channel remains connected until it is disconnected or closed. Whether or not a datagram channel is connected may be determined by invoking its {@link #isConnected isConnected} method. <p> Socket options are configured using the {@link #setOption(SocketOption,Object) setOption} method. A datagram channel to an Internet Protocol socket supports the following options: <blockquote> <table border summary="Socket options"> <tr> <th>Option Name</th> <th>Description</th> </tr> <tr> <td> {@link java.net.StandardSocketOptions#SO_SNDBUF SO_SNDBUF} </td> <td> The size of the socket send buffer </td> </tr> <tr> <td> {@link java.net.StandardSocketOptions#SO_RCVBUF SO_RCVBUF} </td> <td> The size of the socket receive buffer </td> </tr> <tr> <td> {@link java.net.StandardSocketOptions#SO_REUSEADDR SO_REUSEADDR} </td> <td> Re-use address </td> </tr> <tr> <td> {@link java.net.StandardSocketOptions#SO_BROADCAST SO_BROADCAST} </td> <td> Allow transmission of broadcast datagrams </td> </tr> <tr> <td> {@link java.net.StandardSocketOptions#IP_TOS IP_TOS} </td> <td> The Type of Service (ToS) octet in the Internet Protocol (IP) header </td> </tr> <tr> <td> {@link java.net.StandardSocketOptions#IP_MULTICAST_IF IP_MULTICAST_IF} </td> <td> The network interface for Internet Protocol (IP) multicast datagrams </td> </tr> <tr> <td> {@link java.net.StandardSocketOptions#IP_MULTICAST_TTL IP_MULTICAST_TTL} </td> <td> The <em>time-to-live</em> for Internet Protocol (IP) multicast datagrams </td> </tr> <tr> <td> {@link java.net.StandardSocketOptions#IP_MULTICAST_LOOP IP_MULTICAST_LOOP} </td> <td> Loopback for Internet Protocol (IP) multicast datagrams </td> </tr> </table> </blockquote> Additional (implementation specific) options may also be supported. <p> Datagram channels are safe for use by multiple concurrent threads. They support concurrent reading and writing, though at most one thread may be reading and at most one thread may be writing at any given time. </p> @author Mark Reinhold @author JSR-51 Expert Group @since 1.4 */ var DatagramChannel = { /**Opens a datagram channel. <p> The new channel is created by invoking the {@link java.nio.channels.spi.SelectorProvider#openDatagramChannel() openDatagramChannel} method of the system-wide default {@link java.nio.channels.spi.SelectorProvider} object. The channel will not be connected. <p> The {@link ProtocolFamily ProtocolFamily} of the channel's socket is platform (and possibly configuration) dependent and therefore unspecified. The {@link #open(ProtocolFamily) open} allows the protocol family to be selected when opening a datagram channel, and should be used to open datagram channels that are intended for Internet Protocol multicasting. @return {Object {java.nio.channels.DatagramChannel}} A new datagram channel @throws IOException If an I/O error occurs */ open : function( ) {}, /**Opens a datagram channel. <p> The {@code family} parameter is used to specify the {@link ProtocolFamily}. If the datagram channel is to be used for IP multicasting then this should correspond to the address type of the multicast groups that this channel will join. <p> The new channel is created by invoking the {@link java.nio.channels.spi.SelectorProvider#openDatagramChannel(ProtocolFamily) openDatagramChannel} method of the system-wide default {@link java.nio.channels.spi.SelectorProvider} object. The channel will not be connected. @param {Object {ProtocolFamily}} family The protocol family @return {Object {java.nio.channels.DatagramChannel}} A new datagram channel @throws UnsupportedOperationException If the specified protocol family is not supported. For example, suppose the parameter is specified as {@link java.net.StandardProtocolFamily#INET6 StandardProtocolFamily.INET6} but IPv6 is not enabled on the platform. @throws IOException If an I/O error occurs @since 1.7 */ open : function( ) {}, /**Returns an operation set identifying this channel's supported operations. <p> Datagram channels support reading and writing, so this method returns <tt>(</tt>{@link java.nio.channels.SelectionKey#OP_READ} <tt>|</tt> {@link java.nio.channels.SelectionKey#OP_WRITE}<tt>)</tt>. </p> @return {Number} The valid-operation set */ validOps : function( ) {}, /** @throws AlreadyBoundException {@inheritDoc} @throws UnsupportedAddressTypeException {@inheritDoc} @throws ClosedChannelException {@inheritDoc} @throws IOException {@inheritDoc} @throws SecurityException If a security manager has been installed and its {@link SecurityManager#checkListen checkListen} method denies the operation @since 1.7 */ bind : function( ) {}, /** @throws UnsupportedOperationException {@inheritDoc} @throws IllegalArgumentException {@inheritDoc} @throws ClosedChannelException {@inheritDoc} @throws IOException {@inheritDoc} @since 1.7 */ setOption : function( ) {}, /**Retrieves a datagram socket associated with this channel. <p> The returned object will not declare any public methods that are not declared in the {@link java.net.DatagramSocket} class. </p> @return {Object {java.net.DatagramSocket}} A datagram socket associated with this channel */ socket : function( ) {}, /**Tells whether or not this channel's socket is connected. @return {Boolean} {@code true} if, and only if, this channel's socket is {@link #isOpen open} and connected */ isConnected : function( ) {}, /**Connects this channel's socket. <p> The channel's socket is configured so that it only receives datagrams from, and sends datagrams to, the given remote <i>peer</i> 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. <p> This method performs exactly the same security checks as the {@link java.net.DatagramSocket#connect connect} method of the {@link java.net.DatagramSocket} class. That is, if a security manager has been installed then this method verifies that its {@link java.lang.SecurityManager#checkAccept checkAccept} and {@link java.lang.SecurityManager#checkConnect checkConnect} methods permit datagrams to be received from and sent to, respectively, the given remote address. <p> 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 bound then this method will first cause the socket to be bound to an address that is assigned automatically, as if invoking the {@link #bind bind} method with a parameter of {@code null}. </p> @param {Object {SocketAddress}} remote The remote address to which this channel is to be connected @return {Object {java.nio.channels.DatagramChannel}} This datagram channel @throws ClosedChannelException If this channel is closed @throws AsynchronousCloseException If another thread closes this channel while the connect operation is in progress @throws 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 @throws SecurityException If a security manager has been installed and it does not permit access to the given remote address @throws IOException If some other I/O error occurs */ connect : function( ) {}, /**Disconnects this channel's socket. <p> 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. <p> 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. <p> If this channel's socket is not connected, or if the channel is closed, then invoking this method has no effect. </p> @return {Object {java.nio.channels.DatagramChannel}} This datagram channel @throws IOException If some other I/O error occurs */ disconnect : function( ) {}, /**Returns the remote address to which this channel's socket is connected. @return {Object {java.net.SocketAddress}} The remote address; {@code null} if the channel's socket is not connected @throws ClosedChannelException If the channel is closed @throws IOException If an I/O error occurs @since 1.7 */ getRemoteAddress : function( ) {}, /**Receives a datagram via this channel. <p> 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 <tt>null</tt>. <p> The datagram is transferred into the given byte buffer starting at its current position, as if by a regular {@link java.nio.channels.ReadableByteChannel#read(java.nio.ByteBuffer) 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. <p> This method performs exactly the same security checks as the {@link java.net.DatagramSocket#receive receive} method of the {@link java.net.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 {@link java.lang.SecurityManager#checkAccept checkAccept} method. The overhead of this security check can be avoided by first connecting the socket via the {@link #connect connect} method. <p> 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. If this channel's 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 {@link #bind bind} method with a parameter of {@code null}. </p> @param {Object {ByteBuffer}} dst The buffer into which the datagram is to be transferred @return {Object {java.net.SocketAddress}} The datagram's source address, or <tt>null</tt> if this channel is in non-blocking mode and no datagram was immediately available @throws ClosedChannelException If this channel is closed @throws AsynchronousCloseException If another thread closes this channel while the read operation is in progress @throws 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 @throws SecurityException If a security manager has been installed and it does not permit datagrams to be accepted from the datagram's sender @throws IOException If some other I/O error occurs */ receive : function( ) {}, /**Sends a datagram via this channel. <p> 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. <p> The datagram is transferred from the byte buffer as if by a regular {@link java.nio.channels.WritableByteChannel#write(java.nio.ByteBuffer) write} operation. <p> This method performs exactly the same security checks as the {@link java.net.DatagramSocket#send send} method of the {@link java.net.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 {@link java.lang.SecurityManager#checkConnect checkConnect} method. The overhead of this security check can be avoided by first connecting the socket via the {@link #connect connect} method. <p> 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. If this channel's socket is not bound then this method will first cause the socket to be bound to an address that is assigned automatically, as if by invoking the {@link #bind bind} method with a parameter of {@code null}. </p> @param {Object {ByteBuffer}} src The buffer containing the datagram to be sent @param {Object {SocketAddress}} target The address to which the datagram is to be sent @return {Number} 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 ClosedChannelException If this channel is closed @throws AsynchronousCloseException If another thread closes this channel while the read operation is in progress @throws 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 @throws SecurityException If a security manager has been installed and it does not permit datagrams to be sent to the given address @throws IOException If some other I/O error occurs */ send : function( ) {}, /**Reads a datagram from this channel. <p> 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 {@link java.nio.channels.ReadableByteChannel} interface. </p> @throws NotYetConnectedException If this channel's socket is not connected */ read : function( ) {}, /**Reads a datagram from this channel. <p> 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 {@link java.nio.channels.ScatteringByteChannel} interface. </p> @throws NotYetConnectedException If this channel's socket is not connected */ read : function( ) {}, /**Reads a datagram from this channel. <p> 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 {@link java.nio.channels.ScatteringByteChannel} interface. </p> @throws NotYetConnectedException If this channel's socket is not connected */ read : function( ) {}, /**Writes a datagram to this channel. <p> 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 {@link java.nio.channels.WritableByteChannel} interface. </p> @throws NotYetConnectedException If this channel's socket is not connected */ write : function( ) {}, /**Writes a datagram to this channel. <p> 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 {@link java.nio.channels.GatheringByteChannel} interface. </p> @return {Number} 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 */ write : function( ) {}, /**Writes a datagram to this channel. <p> 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 {@link java.nio.channels.GatheringByteChannel} interface. </p> @return {Number} 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 */ write : function( ) {}, /**{@inheritDoc} <p> If there is a security manager set, its {@code checkConnect} method is called with the local address and {@code -1} as its arguments to see if the operation is allowed. If the operation is not allowed, a {@code SocketAddress} representing the {@link java.net.InetAddress#getLoopbackAddress loopback} address and the local port of the channel's socket is returned. @return {Object {java.net.SocketAddress}} The {@code SocketAddress} that the socket is bound to, or the {@code SocketAddress} representing the loopback address if denied by the security manager, or {@code null} if the channel's socket is not bound @throws ClosedChannelException {@inheritDoc} @throws IOException {@inheritDoc} */ getLocalAddress : function( ) {}, };