Customer Reviews

JMX: Managing J2EE with Java Management Extensions (Java (Sams))

5 star:		(5)
4 star:		(2)
3 star:		(4)
2 star:		(0)
1 star:		(0)

 

 

This book will be of particular interest to you if you're using JBoss as your app server, as JMX forms the fundamental glue used to implement the JBoss server.

The book starts out with some nice introductory coverage for Standard MBeans, which are about the most dirt simple classes to code so I expected some good writing here. From there we start getting into Dynamic MBeans where the fun really begins. I was particularly interested in the implementation of ModelMBeans, which are dynamic MBeans that can map to a resource (like a printer for example) and provide automated attribute caching etc.

While the Dynamic MBean coverage was fairly adequate I was pretty disappointed with the ModelMBean coverage. Not enough time was spent describing all the Info classes and Descriptor attributes you need to implement. I spent a lot of time experimenting, reading the JSRs, and working through a subsequent ModelMBean implementation chapter to figure things out. There are also numerous bugs in the sample code for ModelMBeans.

The Chapter discussing the MBeanServer was a little light but reasonably well done. Enough to help you understand how it works which is all you need to program with anyway.

One sorely lacking area is JMX notifications. The interfaces are briefly mentioned, but there is little by way of sample code, or in depth discussion of the default JMX notifications. Since notifications are based on the AWT Event model you can find plenty of other source material for how the notification mechanism works, but I'd like to see more detail on the JMX standard messages etc.

I enjoyed the JMX standard services section. They were very instructive, and helped indirectly patch together some of the notifcication stuff.

The JBoss chapter is, of course, quite good with detailed information about how JBoss uses JMX, how everything fits together in JBoss with JMX. All in all it's a great case study of what you might do with JMX.

This book was a good introduction to JMX, but I felt it lacking in certain areas of detail. Since there are relatively few JMX books (in fact I think this might be the only one) it's not a waste of money, just not as insghtful as I'd hoped.

This is the only book available on JMX and the authors makes a diligent effort to explain the subject and they succeed upto a point. The writing is lucid and the treatment is both detailed and comprehensive. It covers all the main topics - the various types of MBeans, Agent services, protocol handlers etc.However the book is marred by an unfortunate expository style.

The authors prefer to go from bottom up from the lowest level of detail whereas most of us would prefer the opposite approach and the reader is likely to keep missing the overall picture. For instance in the chapter on ModelMBeans all the details are covered and only then does the book give a sample program to see what is being talked about. The same problem occurs in the chapter on XBeans. It would have been a lot simpler if the authors had simply shown how to create the MBeanInfo from an XML file which is useful in itself.

This brings up another issue. The authors for some reason feel compelled to drag in irrelevant packages. For instance in parsing the XML file for the XBean they use JDOM. Nothing against JDOM but since we can expect anyone dealing with XML to know DOM this becomes a needless distraction even if a minor one.

Things really come to a head in chapter 9 ( Protocol Handlers) where all these tendencies combine into incoherence.The authors use Dynamic Proxies , Command pattern etc etc. Wow. This chapter would have been a great deal clearer if the authors has spent a page explaining the overall architecture, some sequence diagrams etc.

To summarize, a good reference and a passable introduction for JMX but be prepared to work at it.

While it is true that this is currently the only book on the market that tackles the subject of JMX, I can't imagine a better one emerging once the flood of copycat titles hits the shelves. This book was written by experts who code with JMX on a daily basis, the JBoss Group. So many Java books these days are either written by technical writers who have never used the API, or by hardcore programmers with no idea how to write a readable book. I was pleasantly surprised by how easily I was able to pick up the material. I had tried to learn JMX by reading the specification, and it was an excruciating experience. This book doesn't require a Ph.D to understand it (only to write it. ;-)

JMX is not for Java or J2EE newbies, but for someone with solid J2EE experience who is interested in learning what makes a commercial grade application server tick underneath, this book will provide the foundation.

You just can't beat it.

As to the previous reviewer who wonders if anyone else is using JMX besides JBoss, how about BEA? Weblogic is also now based on a JMX framework. As are numerous commercial and open source J2EE products. How are they using this technology? Read this book to find out.

The book covers the JMX specification from Sun.

The spec is still in its early days, but has lots of potential.

The book covers JMX in a very readable way, regularly providing code samples and taking you through them carefully. It would be handy to be able to download the samples - but there was no obvious link for that - perhaps its in the JBossMX open source project?

It starts with the basics of JMX and builds upon that - so that you aren't thrown in at the deep end. Going from Standard MBeans to Dynamic and Model MBeans. The actual JMX agent is then covered well. It then looks at various ways to connect to the server - using adaptors and connectors.

It usefully provides a comparison with SNMP, as well showing how you can use an SNMP Adaptor.

The coverage of the XMBean has almost too much code and gets a little tricky to follow - more due to the quantity of sample code rather than the actual subject - maybe if the code was in a slightly smaller font it would have helped indicate the relative importance - that is don't forget the wood that the trees are in.

If you are building Java servers or using a JMX based server then you need to know about JMX. This book provides details on what JMX is, where its going and how to use it and thus is required reading.

First reading this book and then the JDMK 5.0 Tutorial from Sun I was struck by how much of it is copied from the tutorial. The tutorial seems very well written and complete, and I would recomend it before this book.

I bought the book and it reads extremelly well, it is well written, pedagogically clear. You can tell these guys are also involved in training. It covers the full spec, which is nice and the advanced parts are really interesting. The XMBean part is amazing and the parts on JBoss as well. This is what you get when the authors are "Open Source" superstars I guess, you get a straightforward presentation on what to do with the technology. Books should always be written by real active coders who use it in depth (which is the case at JBoss group). In response to another review, we are using JBoss' JMX to boot services and management through the unified JBoss view. Very simple, very elegant and the book really covers this in depth.

The only criticism I have is that I would have preferred less advanced JBoss and more spec coverage.

In any case, it is the first book on the market on the topic and the bar has been set high for the books to follow.

Although the contents in the books are a little haphazard and the samples don't run out of the box, its has excellent content.
This is definately not an intro to JMX if you're not ready to poke around.
Interestingly the difficulty in running the samples and the poking around ultimately led me to get a much deeper understanding of the JMX concept.
Its sort of like how you remember the directions well after you've been lost a few times and havinng to figure your way out of it.
If you use open source software and are used to poking around to troubleshoot its an excellent book. Just don't except too much handholding.
Thanks guys for introducing me to the fascinating world of loosely coupled systems based on JMX and dynamic proxies!!

The example code, ...doesn't match the examples in the book. The files are all in a single directory instead of being seperated by chapter. This makes it more difficult to work with.

Some of the examples will no longer compile due to changes in the JMX spec. There's no errata files.

Other than the difficulty of the examples, the book provides a good introduction to JMX.

This book is great for anyone wanting to work with JMX. I've read the JMX spec. It was long, boring and hard to understand. This book really takes the mistery out of JMX. It lays out all the components in an easy to understand way. It's readable while still cutting to the chase of explaining and developing JMX management solutions. The examples are good and complete. A must have for any serious enterprise developer.

I picked up this book the week it came out and am not sorry I did. JMX is a pretty significant Java technology because it provides a standard framework through which you can implement remote management of your Java applications. If you've ever considered adding SNMP capability to your programs, then you'll want to study up on JMX. JMX already has the support of Sun (of course), IBM, BEA, JBoss and quite a few others, and there's even an OpenJMX project if you want a truly Free implementation of it.

Anyway, this book is well written and covers a lot of ground, and like the previous reviews have said, these guys know their stuff and work with it every day....