Debug Console Architecture


The Geronimo debug console provides you with direct access to the set of objects managed by the Geronimo kernel. These objects are components that make up the servers within Geronimo. You know from Chapter 5 that these components are called GBeans. For example, Tomcat is represented by such a set of GBeans in Geronimo. Other than having its lifecycle (start, stop, and so on) managed by the Geronimo container, a GBean can optionally expose other attributes or operations for management purposes.

A standard JSR exists that specifies how Java components should expose attributes, operations, and events for management purposes. This specification is JSR-3, Java Management Extensions (JMX). Geronimo’s GBeans are JMX-manageable - providing management features for any agent or management system compatible with JMX.

In fact, Geronimo was designed to be manageable from day one. As such, the container actually provides the facility to expose attributes via JMX. All a GBean has to do is define the properties (attributes) that it wants exposed. Not every GBean will have JMX-manageable attributes, however. The ability to expose these features for external management is optional. Some specialized or customized Geronimo assembly may also choose to turn off support for JMX altogether. However, the standard J2EE 1.4 certified distribution of Geronimo does support JMX, and it is through this built-in support that the debug console functions.

You will need some background on JMX and the JSR-77 specification before you can fully appreciate how the debug console can be really useful. The following two sections provide the prerequisite overview and an explanation of key concepts and terms.




Professional Apache Geronimo
Professional Apache Geronimo (Wrox Professional Guides)
ISBN: 0471785431
EAN: 2147483647
Year: 2004
Pages: 148

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net