/**
* Creates a datagram socket, bound to the specified local socket address.
*
* <p>If, if the address is <code>null</code>, creates an unbound socket.
*
* <p>
*
* <p>If there is a security manager, its <code>checkListen</code> 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.
*
* @param bindaddr local socket address to bind, or <code>null</code> for an unbound socket.
* @exception SocketException if the socket could not be opened, or the socket could not bind to
* the specified local port.
* @exception SecurityException if a security manager exists and its <code>checkListen</code>
* method doesn't allow the operation.
* @see SecurityManager#checkListen
* @since 1.4
*/
public DatagramSocket(SocketAddress bindaddr) throws SocketException {
// create a datagram socket.
createImpl();
if (bindaddr != null) {
bind(bindaddr);
}
}
/**
* Constructs a datagram socket and binds it to any available port on the local host machine. The
* socket will be bound to the {@link InetAddress#isAnyLocalAddress wildcard} address, an IP
* address chosen by the kernel.
*
* <p>If there is a security manager, its <code>checkListen</code> method is first called with 0
* as its argument to ensure the operation is allowed. This could result in a SecurityException.
*
* @exception SocketException if the socket could not be opened, or the socket could not bind to
* the specified local port.
* @exception SecurityException if a security manager exists and its <code>checkListen</code>
* method doesn't allow the operation.
* @see SecurityManager#checkListen
*/
public DatagramSocket() throws SocketException {
// create a datagram socket.
createImpl();
try {
bind(new InetSocketAddress(0));
} catch (SocketException se) {
throw se;
} catch (IOException e) {
throw new SocketException(e.getMessage());
}
}
/**
* Get the <code>DatagramSocketImpl</code> attached to this socket, creating it if necessary.
*
* @return the <code>DatagramSocketImpl</code> attached to that DatagramSocket
* @throws SocketException if creation fails.
* @since 1.4
*/
DatagramSocketImpl getImpl() throws SocketException {
if (!created) createImpl();
return impl;
}