| /* |
| * 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 |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package sun.management.jdp; |
| |
| import java.io.IOException; |
| import java.net.InetAddress; |
| import java.net.UnknownHostException; |
| import java.util.UUID; |
| |
| import java.lang.management.ManagementFactory; |
| import java.lang.management.RuntimeMXBean; |
| import java.lang.reflect.Field; |
| import java.lang.reflect.Method; |
| import sun.management.VMManagement; |
| |
| /** |
| * JdpController is responsible to create and manage a broadcast loop |
| * |
| * <p> Other part of code has no access to broadcast loop and have to use |
| * provided static methods |
| * {@link #startDiscoveryService(InetAddress,int,String,String) startDiscoveryService} |
| * and {@link #stopDiscoveryService() stopDiscoveryService}</p> |
| * <p>{@link #startDiscoveryService(InetAddress,int,String,String) startDiscoveryService} could be called multiple |
| * times as it stops the running service if it is necessary. Call to {@link #stopDiscoveryService() stopDiscoveryService} |
| * ignored if service isn't run</p> |
| * |
| * |
| * </p> |
| * |
| * <p> System properties below could be used to control broadcast loop behavior. |
| * Property below have to be set explicitly in command line. It's not possible to |
| * set it in management.config file. Careless changes of these properties could |
| * lead to security or network issues. |
| * <ul> |
| * <li>com.sun.management.jdp.ttl - set ttl for broadcast packet</li> |
| * <li>com.sun.management.jdp.pause - set broadcast interval in seconds</li> |
| * <li>com.sun.management.jdp.source_addr - an address of interface to use for broadcast</li> |
| * </ul> |
| </p> |
| * <p>null parameters values are filtered out on {@link JdpPacketWriter} level and |
| * corresponding keys are not placed to packet.</p> |
| */ |
| public final class JdpController { |
| |
| private static class JDPControllerRunner implements Runnable { |
| |
| private final JdpJmxPacket packet; |
| private final JdpBroadcaster bcast; |
| private final int pause; |
| private volatile boolean shutdown = false; |
| |
| private JDPControllerRunner(JdpBroadcaster bcast, JdpJmxPacket packet, int pause) { |
| this.bcast = bcast; |
| this.packet = packet; |
| this.pause = pause; |
| } |
| |
| @Override |
| public void run() { |
| try { |
| while (!shutdown) { |
| bcast.sendPacket(packet); |
| try { |
| Thread.sleep(this.pause); |
| } catch (InterruptedException e) { |
| // pass |
| } |
| } |
| |
| } catch (IOException e) { |
| // pass; |
| } |
| |
| // It's not possible to re-use controller, |
| // nevertheless reset shutdown variable |
| try { |
| stop(); |
| bcast.shutdown(); |
| } catch (IOException ex) { |
| // pass - ignore IOException during shutdown |
| } |
| } |
| |
| public void stop() { |
| shutdown = true; |
| } |
| } |
| private static JDPControllerRunner controller = null; |
| |
| private JdpController(){ |
| // Don't allow to instantiate this class. |
| } |
| |
| // Utility to handle optional system properties |
| // Parse an integer from string or return default if provided string is null |
| private static int getInteger(String val, int dflt, String msg) throws JdpException { |
| try { |
| return (val == null) ? dflt : Integer.parseInt(val); |
| } catch (NumberFormatException ex) { |
| throw new JdpException(msg); |
| } |
| } |
| |
| // Parse an inet address from string or return default if provided string is null |
| private static InetAddress getInetAddress(String val, InetAddress dflt, String msg) throws JdpException { |
| try { |
| return (val == null) ? dflt : InetAddress.getByName(val); |
| } catch (UnknownHostException ex) { |
| throw new JdpException(msg); |
| } |
| } |
| |
| // Get the process id of the current running Java process |
| private static Integer getProcessId() { |
| try { |
| // Get the current process id using a reflection hack |
| RuntimeMXBean runtime = ManagementFactory.getRuntimeMXBean(); |
| Field jvm = runtime.getClass().getDeclaredField("jvm"); |
| jvm.setAccessible(true); |
| |
| VMManagement mgmt = (sun.management.VMManagement) jvm.get(runtime); |
| Method pid_method = mgmt.getClass().getDeclaredMethod("getProcessId"); |
| pid_method.setAccessible(true); |
| Integer pid = (Integer) pid_method.invoke(mgmt); |
| return pid; |
| } catch(Exception ex) { |
| return null; |
| } |
| } |
| |
| |
| /** |
| * Starts discovery service |
| * |
| * @param address - multicast group address |
| * @param port - udp port to use |
| * @param instanceName - name of running JVM instance |
| * @param url - JMX service url |
| * @throws IOException |
| */ |
| public static synchronized void startDiscoveryService(InetAddress address, int port, String instanceName, String url) |
| throws IOException, JdpException { |
| |
| // Limit packet to local subnet by default |
| int ttl = getInteger( |
| System.getProperty("com.sun.management.jdp.ttl"), 1, |
| "Invalid jdp packet ttl"); |
| |
| // Broadcast once a 5 seconds by default |
| int pause = getInteger( |
| System.getProperty("com.sun.management.jdp.pause"), 5, |
| "Invalid jdp pause"); |
| |
| // Converting seconds to milliseconds |
| pause = pause * 1000; |
| |
| // Allow OS to choose broadcast source |
| InetAddress sourceAddress = getInetAddress( |
| System.getProperty("com.sun.management.jdp.source_addr"), null, |
| "Invalid source address provided"); |
| |
| // Generate session id |
| UUID id = UUID.randomUUID(); |
| |
| JdpJmxPacket packet = new JdpJmxPacket(id, url); |
| |
| // Don't broadcast whole command line for security reason. |
| // Strip everything after first space |
| String javaCommand = System.getProperty("sun.java.command"); |
| if (javaCommand != null) { |
| String[] arr = javaCommand.split(" ", 2); |
| packet.setMainClass(arr[0]); |
| } |
| |
| // Put optional explicit java instance name to packet, if user doesn't specify |
| // it the key is skipped. PacketWriter is responsible to skip keys having null value. |
| packet.setInstanceName(instanceName); |
| |
| // Set rmi server hostname if it explicitly specified by user with |
| // java.rmi.server.hostname |
| String rmiHostname = System.getProperty("java.rmi.server.hostname"); |
| packet.setRmiHostname(rmiHostname); |
| |
| // Set broadcast interval |
| packet.setBroadcastInterval(new Integer(pause).toString()); |
| |
| // Set process id |
| Integer pid = getProcessId(); |
| if (pid != null) { |
| packet.setProcessId(pid.toString()); |
| } |
| |
| JdpBroadcaster bcast = new JdpBroadcaster(address, sourceAddress, port, ttl); |
| |
| // Stop discovery service if it's already running |
| stopDiscoveryService(); |
| |
| controller = new JDPControllerRunner(bcast, packet, pause); |
| |
| Thread t = new Thread(controller, "JDP broadcaster"); |
| t.setDaemon(true); |
| t.start(); |
| } |
| |
| /** |
| * Stop running discovery service, |
| * it's safe to attempt to stop not started service |
| */ |
| public static synchronized void stopDiscoveryService() { |
| if ( controller != null ){ |
| controller.stop(); |
| controller = null; |
| } |
| } |
| } |