/*
 * Copyright (c) 2003, 2012, 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;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import java.lang.management.ManagementFactory;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;
import java.text.MessageFormat;

import java.util.MissingResourceException;
import java.util.Properties;
import java.util.ResourceBundle;

import javax.management.remote.JMXConnectorServer;
import javax.management.remote.JMXServiceURL;

import static sun.management.AgentConfigurationError.*;
import sun.management.jmxremote.ConnectorBootstrap;
import sun.management.jdp.JdpController;
import sun.management.jdp.JdpException;
import sun.misc.VMSupport;

This Agent is started by the VM when -Dcom.sun.management.snmp or -Dcom.sun.management.jmxremote is set. This class will be loaded by the system class loader. Also jmx framework could be started by jcmd
/** * This Agent is started by the VM when -Dcom.sun.management.snmp * or -Dcom.sun.management.jmxremote is set. This class will be * loaded by the system class loader. Also jmx framework could * be started by jcmd */
public class Agent { // management properties private static Properties mgmtProps; private static ResourceBundle messageRB; private static final String CONFIG_FILE = "com.sun.management.config.file"; private static final String SNMP_PORT = "com.sun.management.snmp.port"; private static final String JMXREMOTE = "com.sun.management.jmxremote"; private static final String JMXREMOTE_PORT = "com.sun.management.jmxremote.port"; private static final String RMI_PORT = "com.sun.management.jmxremote.rmi.port"; private static final String ENABLE_THREAD_CONTENTION_MONITORING = "com.sun.management.enableThreadContentionMonitoring"; private static final String LOCAL_CONNECTOR_ADDRESS_PROP = "com.sun.management.jmxremote.localConnectorAddress"; private static final String SNMP_ADAPTOR_BOOTSTRAP_CLASS_NAME = "sun.management.snmp.AdaptorBootstrap"; private static final String JDP_DEFAULT_ADDRESS = "224.0.23.178"; private static final int JDP_DEFAULT_PORT = 7095; // The only active agent allowed private static JMXConnectorServer jmxServer = null; // Parse string com.sun.management.prop=xxx,com.sun.management.prop=yyyy // and return property set if args is null or empty // return empty property set private static Properties parseString(String args){ Properties argProps = new Properties(); if (args != null) { for (String option : args.split(",")) { String s[] = option.split("=", 2); String name = s[0].trim(); String value = (s.length > 1) ? s[1].trim() : ""; if (!name.startsWith("com.sun.management.")) { error(INVALID_OPTION, name); } argProps.setProperty(name, value); } } return argProps; } // invoked by -javaagent or -Dcom.sun.management.agent.class public static void premain(String args) throws Exception { agentmain(args); } // invoked by attach mechanism public static void agentmain(String args) throws Exception { if (args == null || args.length() == 0) { args = JMXREMOTE; // default to local management } Properties arg_props = parseString(args); // Read properties from the config file Properties config_props = new Properties(); String fname = arg_props.getProperty(CONFIG_FILE); readConfiguration(fname, config_props); // Arguments override config file config_props.putAll(arg_props); startAgent(config_props); } // jcmd ManagementAgent.start_local entry point // Also called due to command-line via startAgent() private static synchronized void startLocalManagementAgent(){ Properties agentProps = VMSupport.getAgentProperties(); // start local connector if not started if (agentProps.get(LOCAL_CONNECTOR_ADDRESS_PROP) == null) { JMXConnectorServer cs = ConnectorBootstrap.startLocalConnectorServer(); String address = cs.getAddress().toString(); // Add the local connector address to the agent properties agentProps.put(LOCAL_CONNECTOR_ADDRESS_PROP, address); try { // export the address to the instrumentation buffer ConnectorAddressLink.export(address); } catch (Exception x) { // Connector server started but unable to export address // to instrumentation buffer - non-fatal error. warning(EXPORT_ADDRESS_FAILED, x.getMessage()); } } } // jcmd ManagementAgent.start entry point // This method starts the remote JMX agent and starts neither // the local JMX agent nor the SNMP agent // @see #startLocalManagementAgent and also @see #startAgent. private static synchronized void startRemoteManagementAgent(String args) throws Exception { if (jmxServer != null) { throw new RuntimeException(getText(INVALID_STATE, "Agent already started")); } Properties argProps = parseString(args); Properties configProps = new Properties(); // Load the management properties from the config file // if config file is not specified readConfiguration implicitly // reads <java.home>/lib/management/management.properties String fname = System.getProperty(CONFIG_FILE); readConfiguration(fname, configProps); // management properties can be overridden by system properties // which take precedence Properties sysProps = System.getProperties(); synchronized(sysProps){ configProps.putAll(sysProps); } // if user specifies config file into command line for either // jcmd utilities or attach command it overrides properties set in // command line at the time of VM start String fnameUser = argProps.getProperty(CONFIG_FILE); if (fnameUser != null) { readConfiguration(fnameUser, configProps); } // arguments specified in command line of jcmd utilities // override both system properties and one set by config file // specified in jcmd command line configProps.putAll(argProps); // jcmd doesn't allow to change ThreadContentionMonitoring, but user // can specify this property inside config file, so enable optional // monitoring functionality if this property is set final String enableThreadContentionMonitoring = configProps.getProperty(ENABLE_THREAD_CONTENTION_MONITORING); if (enableThreadContentionMonitoring != null) { ManagementFactory.getThreadMXBean(). setThreadContentionMonitoringEnabled(true); } String jmxremotePort = configProps.getProperty(JMXREMOTE_PORT); if (jmxremotePort != null) { jmxServer = ConnectorBootstrap. startRemoteConnectorServer(jmxremotePort, configProps); startDiscoveryService(configProps); } } private static synchronized void stopRemoteManagementAgent() throws Exception { JdpController.stopDiscoveryService(); if (jmxServer != null) { ConnectorBootstrap.unexportRegistry(); // Attempt to stop already stopped agent // Don't cause any errors. jmxServer.stop(); jmxServer = null; } } private static void startAgent(Properties props) throws Exception { String snmpPort = props.getProperty(SNMP_PORT); String jmxremote = props.getProperty(JMXREMOTE); String jmxremotePort = props.getProperty(JMXREMOTE_PORT); // Enable optional monitoring functionality if requested final String enableThreadContentionMonitoring = props.getProperty(ENABLE_THREAD_CONTENTION_MONITORING); if (enableThreadContentionMonitoring != null) { ManagementFactory.getThreadMXBean(). setThreadContentionMonitoringEnabled(true); } try { if (snmpPort != null) { loadSnmpAgent(snmpPort, props); } /* * If the jmxremote.port property is set then we start the * RMIConnectorServer for remote M&M. * * If the jmxremote or jmxremote.port properties are set then * we start a RMIConnectorServer for local M&M. The address * of this "local" server is exported as a counter to the jstat * instrumentation buffer. */ if (jmxremote != null || jmxremotePort != null) { if (jmxremotePort != null) { jmxServer = ConnectorBootstrap. startRemoteConnectorServer(jmxremotePort, props); startDiscoveryService(props); } startLocalManagementAgent(); } } catch (AgentConfigurationError e) { error(e.getError(), e.getParams()); } catch (Exception e) { error(e); } } private static void startDiscoveryService(Properties props) throws IOException { // Start discovery service if requested String discoveryPort = props.getProperty("com.sun.management.jdp.port"); String discoveryAddress = props.getProperty("com.sun.management.jdp.address"); String discoveryShouldStart = props.getProperty("com.sun.management.jmxremote.autodiscovery"); // Decide whether we should start autodicovery service. // To start autodiscovery following conditions should be met: // autodiscovery==true OR (autodicovery==null AND jdp.port != NULL) boolean shouldStart = false; if (discoveryShouldStart == null){ shouldStart = (discoveryPort != null); } else{ try{ shouldStart = Boolean.parseBoolean(discoveryShouldStart); } catch (NumberFormatException e) { throw new AgentConfigurationError("Couldn't parse autodiscovery argument"); } } if (shouldStart) { // port and address are required arguments and have no default values InetAddress address; try { address = (discoveryAddress == null) ? InetAddress.getByName(JDP_DEFAULT_ADDRESS) : InetAddress.getByName(discoveryAddress); } catch (UnknownHostException e) { throw new AgentConfigurationError("Unable to broadcast to requested address", e); } int port = JDP_DEFAULT_PORT; if (discoveryPort != null) { try { port = Integer.parseInt(discoveryPort); } catch (NumberFormatException e) { throw new AgentConfigurationError("Couldn't parse JDP port argument"); } } // Rebuilding service URL to broadcast it String jmxremotePort = props.getProperty(JMXREMOTE_PORT); String rmiPort = props.getProperty(RMI_PORT); JMXServiceURL url = jmxServer.getAddress(); String hostname = url.getHost(); String jmxUrlStr = (rmiPort != null) ? String.format( "service:jmx:rmi://%s:%s/jndi/rmi://%s:%s/jmxrmi", hostname, rmiPort, hostname, jmxremotePort) : String.format( "service:jmx:rmi:///jndi/rmi://%s:%s/jmxrmi", hostname, jmxremotePort); String instanceName = System.getProperty("com.sun.management.jdp.name"); try{ JdpController.startDiscoveryService(address, port, instanceName, jmxUrlStr); } catch(JdpException e){ throw new AgentConfigurationError("Couldn't start JDP service", e); } } } public static Properties loadManagementProperties() { Properties props = new Properties(); // Load the management properties from the config file String fname = System.getProperty(CONFIG_FILE); readConfiguration(fname, props); // management properties can be overridden by system properties // which take precedence Properties sysProps = System.getProperties(); synchronized(sysProps){ props.putAll(sysProps); } return props; } public static synchronized Properties getManagementProperties() { if (mgmtProps == null) { String configFile = System.getProperty(CONFIG_FILE); String snmpPort = System.getProperty(SNMP_PORT); String jmxremote = System.getProperty(JMXREMOTE); String jmxremotePort = System.getProperty(JMXREMOTE_PORT); if (configFile == null && snmpPort == null && jmxremote == null && jmxremotePort == null) { // return if out-of-the-management option is not specified return null; } mgmtProps = loadManagementProperties(); } return mgmtProps; } private static void loadSnmpAgent(String snmpPort, Properties props) { try { // invoke the following through reflection: // AdaptorBootstrap.initialize(snmpPort, props); final Class<?> adaptorClass = Class.forName(SNMP_ADAPTOR_BOOTSTRAP_CLASS_NAME,true,null); final Method initializeMethod = adaptorClass.getMethod("initialize", String.class, Properties.class); initializeMethod.invoke(null,snmpPort,props); } catch (ClassNotFoundException | NoSuchMethodException | IllegalAccessException x) { // snmp runtime doesn't exist - initialization fails throw new UnsupportedOperationException("Unsupported management property: " + SNMP_PORT,x); } catch (InvocationTargetException x) { final Throwable cause = x.getCause(); if (cause instanceof RuntimeException) throw (RuntimeException) cause; else if (cause instanceof Error) throw (Error) cause; // should not happen... throw new UnsupportedOperationException("Unsupported management property: " + SNMP_PORT,cause); } } // read config file and initialize the properties private static void readConfiguration(String fname, Properties p) { if (fname == null) { String home = System.getProperty("java.home"); if (home == null) { throw new Error("Can't find java.home ??"); } StringBuffer defaultFileName = new StringBuffer(home); defaultFileName.append(File.separator).append("lib"); defaultFileName.append(File.separator).append("management"); defaultFileName.append(File.separator).append("management.properties"); // Set file name fname = defaultFileName.toString(); } final File configFile = new File(fname); if (!configFile.exists()) { error(CONFIG_FILE_NOT_FOUND, fname); } InputStream in = null; try { in = new FileInputStream(configFile); BufferedInputStream bin = new BufferedInputStream(in); p.load(bin); } catch (FileNotFoundException e) { error(CONFIG_FILE_OPEN_FAILED, e.getMessage()); } catch (IOException e) { error(CONFIG_FILE_OPEN_FAILED, e.getMessage()); } catch (SecurityException e) { error(CONFIG_FILE_ACCESS_DENIED, fname); } finally { if (in != null) { try { in.close(); } catch (IOException e) { error(CONFIG_FILE_CLOSE_FAILED, fname); } } } } public static void startAgent() throws Exception { String prop = System.getProperty("com.sun.management.agent.class"); // -Dcom.sun.management.agent.class not set so read management // properties and start agent if (prop == null) { // initialize management properties Properties props = getManagementProperties(); if (props != null) { startAgent(props); } return; } // -Dcom.sun.management.agent.class=<agent classname>:<agent args> String[] values = prop.split(":"); if (values.length < 1 || values.length > 2) { error(AGENT_CLASS_INVALID, "\"" + prop + "\""); } String cname = values[0]; String args = (values.length == 2 ? values[1] : null); if (cname == null || cname.length() == 0) { error(AGENT_CLASS_INVALID, "\"" + prop + "\""); } if (cname != null) { try { // Instantiate the named class. // invoke the premain(String args) method Class<?> clz = ClassLoader.getSystemClassLoader().loadClass(cname); Method premain = clz.getMethod("premain", new Class<?>[] { String.class }); premain.invoke(null, /* static */ new Object[] { args }); } catch (ClassNotFoundException ex) { error(AGENT_CLASS_NOT_FOUND, "\"" + cname + "\""); } catch (NoSuchMethodException ex) { error(AGENT_CLASS_PREMAIN_NOT_FOUND, "\"" + cname + "\""); } catch (SecurityException ex) { error(AGENT_CLASS_ACCESS_DENIED); } catch (Exception ex) { String msg = (ex.getCause() == null ? ex.getMessage() : ex.getCause().getMessage()); error(AGENT_CLASS_FAILED, msg); } } } public static void error(String key) { String keyText = getText(key); System.err.print(getText("agent.err.error") + ": " + keyText); throw new RuntimeException(keyText); } public static void error(String key, String[] params) { if (params == null || params.length == 0) { error(key); } else { StringBuffer message = new StringBuffer(params[0]); for (int i = 1; i < params.length; i++) { message.append(" " + params[i]); } error(key, message.toString()); } } public static void error(String key, String message) { String keyText = getText(key); System.err.print(getText("agent.err.error") + ": " + keyText); System.err.println(": " + message); throw new RuntimeException(keyText); } public static void error(Exception e) { e.printStackTrace(); System.err.println(getText(AGENT_EXCEPTION) + ": " + e.toString()); throw new RuntimeException(e); } public static void warning(String key, String message) { System.err.print(getText("agent.err.warning") + ": " + getText(key)); System.err.println(": " + message); } private static void initResource() { try { messageRB = ResourceBundle.getBundle("sun.management.resources.agent"); } catch (MissingResourceException e) { throw new Error("Fatal: Resource for management agent is missing"); } } public static String getText(String key) { if (messageRB == null) { initResource(); } try { return messageRB.getString(key); } catch (MissingResourceException e) { return "Missing management agent resource bundle: key = \"" + key + "\""; } } public static String getText(String key, String... args) { if (messageRB == null) { initResource(); } String format = messageRB.getString(key); if (format == null) { format = "missing resource key: key = \"" + key + "\", " + "arguments = \"{0}\", \"{1}\", \"{2}\""; } return MessageFormat.format(format, (Object[]) args); } }