/*
* Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package sun.management.jdp;
import java.io.IOException;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.NetworkInterface;
import java.net.ProtocolFamily;
import java.net.StandardProtocolFamily;
import java.net.StandardSocketOptions;
import java.nio.ByteBuffer;
import java.nio.channels.DatagramChannel;
import java.nio.channels.UnsupportedAddressTypeException;
/**
* JdpBroadcaster is responsible for sending pre-built JDP packet across a Net
*
* <p> Multicast group address, port number and ttl have to be chosen on upper
* level and passed to broadcaster constructor. Also it's possible to specify
* source address to broadcast from. </p>
*
* <p>JdpBradcaster doesn't perform any validation on a supplied {@code port} and {@code ttl} because
* the allowed values depend on an operating system setup</p>
*
*/
public final class JdpBroadcaster {
private final InetAddress addr;
private final int port;
private final DatagramChannel channel;
/**
* Create a new broadcaster
*
* @param address - multicast group address
* @param srcAddress - address of interface we should use to broadcast.
* @param port - udp port to use
* @param ttl - packet ttl
* @throws IOException
*/
public JdpBroadcaster(InetAddress address, InetAddress srcAddress, int port, int ttl)
throws IOException, JdpException {
this.addr = address;
this.port = port;
ProtocolFamily family = (address instanceof Inet6Address)
? StandardProtocolFamily.INET6 : StandardProtocolFamily.INET;
channel = DatagramChannel.open(family);
channel.setOption(StandardSocketOptions.SO_REUSEADDR, true);
channel.setOption(StandardSocketOptions.IP_MULTICAST_TTL, ttl);
// with srcAddress equal to null, this constructor do exactly the same as
// if srcAddress is not passed
if (srcAddress != null) {
// User requests particular interface to bind to
NetworkInterface interf = NetworkInterface.getByInetAddress(srcAddress);
try {
channel.bind(new InetSocketAddress(srcAddress, 0));
} catch (UnsupportedAddressTypeException ex) {
throw new JdpException("Unable to bind to source address");
}
channel.setOption(StandardSocketOptions.IP_MULTICAST_IF, interf);
}
}
/**
* Create a new broadcaster
*
* @param address - multicast group address
* @param port - udp port to use
* @param ttl - packet ttl
* @throws IOException
*/
public JdpBroadcaster(InetAddress address, int port, int ttl)
throws IOException, JdpException {
this(address, null, port, ttl);
}
/**
* Broadcast pre-built packet
*
* @param packet - instance of JdpPacket
* @throws IOException
*/
public void sendPacket(JdpPacket packet)
throws IOException {
byte[] data = packet.getPacketData();
// Unlike allocate/put wrap don't need a flip afterward
ByteBuffer b = ByteBuffer.wrap(data);
channel.send(b, new InetSocketAddress(addr, port));
}
/**
* Shutdown broadcaster and close underlying socket channel
*
* @throws IOException
*/
public void shutdown() throws IOException {
channel.close();
}
}