JAVA MANAGEMENT EXTENSIONS

' Java Management Extensions' ('JMX') is a Java technology that supplies tools for managing and monitoring applications, system objects, devices (e.g. printers) and service oriented networks. Those resources are represented by objects called MBeans (for ''Managed Bean''). An interesting detail of the API is that classes can be dynamically loaded and instantiated.
JMX 1.0, 1.1 and 1.2 were defined by JSR 3 of the Java Community Process. As of 2006, JMX 2.0 is being developed under JSR 255. The JMX Remote API 1.0 for remote management and monitoring is specified by JSR 160. An extension of the JMX Remote API for Web Services is being developed under JSR 262.
Adopted early on by the J2EE community, JMX is a part of J2SE since version 5.0.
JMX is a trademark of Sun Microsystems, Inc.

Contents

Architecture

Support

See also

References

External links

Architecture

JMX is based on a 3-level architecture:

★ The ''Probe'' level : contains the probes (called MBeans) instrumenting the resources. Also called the ''Instrumentation'' level.

★ The ''Agent'' level : the MBeanServer is the core of JMX. It is an intermediary between the MBean and the applications.

★ The ''Remote Management'' level : enables remote applications to access to the MBeanServer through Connectors and Adaptors. A connector provides full remote access to the MBeanServer API using various communication frameworks (RMI, IIOP, JMS, WS-
★ ...), while an adaptor adapts the API to another protocol (SNMP, ...) or to Web-based GUI (HTML/HTTP, WML/HTTP, ...).
Applications can be generic consoles (such as JConsole and MC4J), or domain-specific (monitoring) applications. External applications can interact with the MBeans through the use of JMX connectors and protocol adapters. Connectors are used to connect an agent with a remote JMX-enabled management application. This form of communication involves a connector in the JMX agent and a connector client in the management application.
Protocol adapters provide a management view of the JMX agent through a given protocol. Management applications that connect to a protocol adapter are usually specific to the given protocol.

Support

JMX is supported at various levels by different vendors:

★ JMX is supported by Java application servers such as JBoss, JOnAS, WebSphere Application Server, WebLogic, Oracle Application Server 10g and Sun Java System Application Server.

★ Systems management tools that support the protocol include HP OpenView.

★ JMX is also supported by servlet containers such as Apache Tomcat, as documented at http://tomcat.apache.org/tomcat-6.0-doc/monitoring.html.

★ MX4J [1] is Open Source JMX for Enterprise Computing.

★ jManage [2] is an open source enterprise-grade JMX Console with web and command-line interfaces.

★ MC4J [3] is an open source visual console for connecting to servers supporting JMX

See also

★ Java Dynamic Management Kit

★ JavaBeans

★ Mbean

★ Metaclass

★ Metaprogramming

★ Reflection

★ Simple network management protocol

★ Network Management

★ JINI

★ OSGi

★ OpenJava

★ OpenC++

References

★ J. Steven Perry: ''Java Management Extensions'', O'Reilly, ISBN 0-596-00245-9

★ Marc Fleury, Juha Lindfors: ''JMX: Managing J2EE with Java Management Extensions'', Sams Publishing, ISBN 0-672-32288-9

★ Jeff Hanson: ''Connecting JMX Clients and Servers: Understanding the Java Management Extensions'', APress L. P., ISBN 1-59059-101-1

★ Benjamin G Sullins, ''Mark B Whipple : JMX in Action: You will also get your first JMX application up and running'', Manning Publications Co. 2002, ISBN 1-930110-56-1

External links

★ JMX on java.sun.com

★ JMX at JBoss.com

★ JSR 255 (JMX 2.0)

★ JSR 3 (JMX 1.0, 1.1, and 1.2)
;Articles

★ "Enabling Component Architectures with JMX" by Marc Fleury and Juha Lindfors

★ "Introducing A New Vendor-Neutral J2EE Management API" by Andreas Schaefer

★ "Java in the management sphere" by Max Goff

★ "Managing J2EE Systems with JMX and JUnit" by Lucas McGregor

★ JMX/JBoss - The microkernel design

★ JMX and jManage