| /** |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.openejb.client; |
| |
| import java.io.IOException; |
| import java.net.DatagramPacket; |
| import java.net.InetAddress; |
| import java.net.InetSocketAddress; |
| import java.net.MulticastSocket; |
| import java.net.SocketException; |
| import java.net.SocketTimeoutException; |
| import java.net.URI; |
| import java.net.URISyntaxException; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * @version $Rev$ $Date$ |
| */ |
| public class MulticastSearch { |
| |
| private static final int BUFF_SIZE = 8192; |
| |
| private final MulticastSocket multicast; |
| |
| public MulticastSearch() throws IOException { |
| this("239.255.3.2", 6142); |
| } |
| |
| public MulticastSearch(final String host, final int port) throws IOException { |
| final InetAddress inetAddress = InetAddress.getByName(host); |
| |
| multicast = new MulticastSocket(port); |
| multicast.joinGroup(inetAddress); |
| multicast.setSoTimeout(500); |
| } |
| |
| public URI search(final int timeout, final TimeUnit milliseconds) throws IOException { |
| return search(new DefaultFilter(), timeout, milliseconds); |
| } |
| |
| public URI search() throws IOException { |
| return search(new DefaultFilter(), 0, TimeUnit.MILLISECONDS); |
| } |
| |
| public URI search(final Filter filter) throws IOException { |
| return search(filter, 0, TimeUnit.MILLISECONDS); |
| } |
| |
| @SuppressWarnings("UseOfSystemOutOrSystemErr") |
| public URI search(final Filter filter, long timeout, final TimeUnit unit) throws IOException { |
| timeout = TimeUnit.MILLISECONDS.convert(timeout, unit); |
| long waited = 0; |
| |
| final byte[] buf = new byte[BUFF_SIZE]; |
| final DatagramPacket packet = new DatagramPacket(buf, 0, buf.length); |
| |
| while (timeout == 0 || waited < timeout) { |
| final long start = System.currentTimeMillis(); |
| try { |
| multicast.receive(packet); |
| if (packet.getLength() > 0) { |
| final String str = new String(packet.getData(), packet.getOffset(), packet.getLength()); |
| try { |
| final URI service = new URI(str); |
| if (service != null && filter.accept(service)) { |
| |
| final String callerHost = ((InetSocketAddress) packet.getSocketAddress()).getAddress().getHostAddress(); |
| final String serviceHost = service.getHost(); |
| |
| if (MulticastPulseClient.isLocalAddress(serviceHost, false)) { |
| if (!MulticastPulseClient.isLocalAddress(callerHost, false)) { |
| //A local service is only available to a local client |
| continue; |
| } |
| } |
| |
| return service; |
| } |
| } catch (URISyntaxException e) { |
| // not a service URI |
| } |
| } |
| } catch (SocketTimeoutException e) { |
| //Ignore |
| } catch (SocketException e) { |
| System.out.println(e.getClass().getName() + ": " + e.getMessage()); |
| } finally { |
| final long stop = System.currentTimeMillis(); |
| waited += stop - start; |
| } |
| } |
| |
| return null; |
| } |
| |
| public interface Filter { |
| boolean accept(URI service); |
| } |
| |
| public static class DefaultFilter implements Filter { |
| @Override |
| public boolean accept(final URI service) { |
| return true; |
| } |
| } |
| } |