| Java Platform, Standard Edition Java Management Extensionsガイド リリース10 E94991-01 |
|
 前 |
 次 |
/*
* Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of Oracle or the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package jini;
import net.jini.core.lookup.ServiceRegistrar;
import net.jini.admin.Administrable;
import net.jini.core.discovery.LookupLocator;
import net.jini.core.lookup.ServiceItem;
import net.jini.core.lookup.ServiceRegistration;
import net.jini.core.entry.Entry;
import net.jini.core.lease.Lease;
import net.jini.core.lookup.ServiceTemplate;
import net.jini.core.lookup.ServiceMatches;
import javax.management.remote.*;
import javax.management.*;
import java.net.MalformedURLException;
import java.util.Map;
import java.util.List;
import java.util.ArrayList;
import java.util.Set;
import java.util.Iterator;
import java.io.IOException;
import java.io.Serializable;
import java.rmi.RMISecurityManager;
/**
* This class demonstrates how to use Jini as a lookup service for
* JSR 160 connectors. It shows how to lookup a JMXConnector from
* the Jini lookup service.
* <p>
* See README file and {@link #main(String[])} for more details.
* <p>
* Make sure to read the section "Binding with Lookup Services" of
* the JMX Remote API 1.0 Specification before looking at this example.
*/
public class Client {
private static boolean debug = false;
/**
* Get a pointer to the Jini Lookup Service.
* (See Jini documentation for more info).
* <p>
* The Jini Lookup Service URL is determined as follows:
* <p>
* If the System property <code>"jini.lookup.url"</code> is provided,
* its value is the Jini Lookup Service URL.
* <p>
* Otherwise, the default URL is assumed to be
* <code>"jini://localhost"</code>
*
* @return a pointer to the Jini Lookup Service.
*/
public static ServiceRegistrar getRegistrar()
throws IOException, ClassNotFoundException, MalformedURLException {
final String jurl =
System.getProperty("jini.lookup.url","jini://localhost");
final LookupLocator lookup = new LookupLocator(jurl);
final ServiceRegistrar registrar = lookup.getRegistrar();
if (registrar instanceof Administrable)
debug("Registry is administrable.");
return registrar;
}
/**
* Lookup JMXConnectors in the Jini Lookup Service.
*
* @param registrar A pointer to the Jini Lookup Service,
* returned by {@link #getRegistrar()}.
* @param name the AgentName of the JMXConnectors that should
* be returned. If <var>name</var> is null, then
* the JMXConnectors for all agents are returned
* (null is an equivalent for a wildcard).
* @return The list of matching JMXConnectors retrieved from
* the Jini Lookup Service.
*/
public static List lookup(ServiceRegistrar registrar,
String name) throws IOException {
final ArrayList list = new ArrayList();
// Returns only JMXConnectors. The filter could be made
// more strict by suplying e.g. RMIConnector.class
// (would only return RMIConnectors).
//
final Class[] classes = new Class[] {JMXConnector.class};
// Will return only those services for which the Name
// attribute was registered. Since JSR 160 specifies that
// the Name attribute is mandatory, this makes it possible
// to filter out all the services that do not conform
// to the spec.
// If <name> is null, then all services for which the
// Name attribute was specified will match, regardless of
// the value of that attribute. Otherwise, only those services
// for which Name matches the specified name will be returned.
//
final Entry[] serviceAttrs = new Entry[] {
// Add here the matching attributes.
new net.jini.lookup.entry.Name(name)
};
// Create a ServiceTemplate to do the matching.
//
ServiceTemplate template =
new ServiceTemplate(null,classes,serviceAttrs);
// Lookup all matching services in the Jini Lookup Service.
//
ServiceMatches matches =
registrar.lookup(template, Integer.MAX_VALUE);
// Retrieve the matching JMX Connectors.
//
for (int i = 0; i < matches.totalMatches; i++) {
debug("Found Service: " + matches.items[i].serviceID);
if (debug) {
// List the lookup attributes that where registered
// for that service.
if (matches.items[i].attributeSets != null) {
final Entry[] attrs = matches.items[i].attributeSets;
for (int j = 0; j < attrs.length ; j++) {
debug("\tAttribute["+j+"]=" + attrs[j]);
}
}
}
if (matches.items[i].service != null) {
// Service could be null if it can't be deserialized, because
// e.g. the class was not found.
// This will not happen with JSR 160 mandatory connectors
// however.
// Get the JMXConnector.
//
JMXConnector c = (JMXConnector)(matches.items[i].service);
debug("Found a JMXConnector: " + c);
// Add the connector to the result list.
list.add(c);
}
}
return list;
}
/**
* List all MBeans and their attributes.
*/
public static void listMBeans(MBeanServerConnection server)
throws IOException {
final Set names = server.queryNames(null,null);
for (final Iterator i=names.iterator(); i.hasNext(); ) {
ObjectName name = (ObjectName)i.next();
System.out.println("Got MBean: "+name);
try {
MBeanInfo info =
server.getMBeanInfo((ObjectName)name);
MBeanAttributeInfo[] attrs = info.getAttributes();
if (attrs == null) continue;
for (int j=0; j<attrs.length; j++) {
if (attrs[j].isReadable()) {
try {
Object o =
server.getAttribute(name,attrs[j].getName());
System.out.println("\t\t" + attrs[j].getName() +
" = "+o);
} catch (Exception x) {
System.err.println("JmxClient failed to get " +
attrs[j].getName());
x.printStackTrace(System.err);
}
}
}
} catch (Exception x) {
System.err.println("JmxClient failed to get MBeanInfo: " + x);
x.printStackTrace(System.err);
}
}
}
/**
* Trace a debug message.
*/
private static void debug(String msg) {
if (debug) System.out.println(msg);
}
/**
* Program Main
* <p>
* Lookup all JMX agents in the Jini Lookup Service and list
* their MBeans and attributes.
* <p>
* You may wish to use the following properties on the Java command line:
* <ul>
* <li><code>-Dagent.name=<AgentName></code>: specifies an
* AgentName to lookup (default is null, meaning any agent).</li>
* <li><code>-Djini.lookup.url=<jini-url></code>:
* the Jini Lookup Service URL (default is "jini://localhost"),
* see {@link #getRegistrar()}.</li>
* <li><code>-Ddebug="true|false"</code>: switch the Client debug flag
* on/off (default is "false").</li>
* </ul>
*/
public static void main(String[] args) {
try {
// Jini requires a security manager.
//
if (System.getSecurityManager() == null)
System.setSecurityManager(new RMISecurityManager());
// Get the value of the debug flag.
//
debug = (Boolean.valueOf(System.getProperty("debug","false"))).
booleanValue();
// Get AgentName to lookup. If not defined, all agents
// are looked up.
//
final String agentName = System.getProperty("agent.name");
// Get a pointer to the Jini Lookup Service.
//
final ServiceRegistrar registrar = getRegistrar();
debug("registrar is: " + registrar);
// Lookup all matching agents in the Jini Lookup Service.
//
List l = lookup(registrar,agentName);
// Attempt to connect to retrieved agents
//
System.out.println("Number of agents found : " + l.size());
int j = 1;
for (Iterator i=l.iterator();i.hasNext();j++) {
JMXConnector c1 = (JMXConnector) i.next();
if (c1 != null) {
// Connect
//
System.out.println(
"----------------------------------------------------");
System.out.println("\tConnecting to agent number "+j);
System.out.println(
"----------------------------------------------------");
debug("JMXConnector is: " + c1);
try {
c1.connect(null);
} catch (IOException x) {
System.err.println("Connection failed: " + x);
if (debug) x.printStackTrace(System.err);
continue;
}
// Get MBeanServerConnection
//
MBeanServerConnection conn =
c1.getMBeanServerConnection();
debug("Connection is:" + conn);
System.out.println("Server domain is: " +
conn.getDefaultDomain());
// List all MBeans
//
try {
listMBeans(conn);
} catch (IOException x) {
System.err.println("Failed to list MBeans: " + x);
if (debug) x.printStackTrace(System.err);
}
// Close connector
//
try {
c1.close();
} catch (IOException x) {
System.err.println("Failed to close connection: " + x);
if (debug) x.printStackTrace(System.err);
}
}
}
} catch (Exception x) {
System.err.println("Unexpected exception caught in main: " + x);
x.printStackTrace(System.err);
}
}
}
