[Java] Jmx

There are some frequently used Mbeans in the JVM that can write a code to get:

public class Test {public    static void Main (string[] args) throws Exception {        Mbeanserver server = Managementfacto Ry.getplatformmbeanserver ();        Set instances = Server.querymbeans (null, NULL);        Iterator Iterator = Instances.iterator ();        while (Iterator.hasnext ()) {            ObjectInstance instance = (objectinstance) iterator.next ();            System.out.println ("MBean Found:");            System.out.println ("Class name:\t" + instance.getclassname ());            System.out.println ("Object name:\t" + instance.getobjectname ());            System.out.println ("****************************************");}}}    

Based on the list, we can obtain the desired information through an mbean, for example, the size of the code cache:

public class Testmbean {final static String pid = "6228";    Final static String connector_address = "com.sun.management.jmxremote.localConnectorAddress";        public static void Main (string[] args) throws Exception {virtualmachine vm = Virtualmachine.attach (PID);        Jmxconnector connector = null;        String connectoraddress = Vm.getagentproperties (). GetProperty (connector_address);                String Agent = Vm.getsystemproperties (). GetProperty ("java.home") + File.separator + "Lib" + File.separator        + "Management-agent.jar";        Vm.loadagent (agent);        Connectoraddress = Vm.getagentproperties (). GetProperty (connector_address);        Jmxserviceurl url = new Jmxserviceurl (connectoraddress);        Connector = jmxconnectorfactory.connect (URL);        Mbeanserverconnection mbeanconn = Connector.getmbeanserverconnection ();        ObjectName name = new ObjectName ("Java.lang:type=memorypool,name=code Cache"); System.out.println (MBEANCONN.GEtattribute (name, "Usage"));        if (connector! = null) {connector.close ();    } Vm.detach (); }}

The classes actually obtained by ObjectName ("Java.lang:type=memorypool,name=code Cache") are:

Sun.management.MemoryPoolImpl

In the GetAttribute (name, "Usage") The corresponding method is called:

Public Java.lang.management.MemoryUsage Getusage () {}

The use of other Mbean is similar to this.

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Assuming that the system's Mbean does not satisfy the need, then we can customize the Mbean, such as the standard Mbean such as the following:

The standard Mbean has several limitations: 1, must implement Interface 2, must have a public type of constructor 3, naming rules public class My implements Mymbean {public    String Gethello () {
   return "Hello World";    }} Public interface Mymbean {public    String Gethello ();}

You can then add this mbean to Mbeanserver:

public class Test {public    static final void main (string[] args) throws Exception {        Mbeanserver mbeanserver = Mana Gementfactory.getplatformmbeanserver ();        ObjectName ObjectName = new ObjectName ("Com.wszt:type=mymbean");        Mbeanserver.creatembean ("My", ObjectName);}    }

attach& usage is the same as above, do not repeat. In addition to the standard Mbean, there are dynamic Mbean, Model Bean, Open Mbean, and similar usage.

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A simple look at JMX is a JVM's management framework, the Mbean is the encapsulation of resources, and then after the agent to be packaged, and finally the interface to provide external to facilitate the use, see:

[Java] Jmx