Professional Apache Tomcat 5

Rating:
Summary: this is the place to start
Review: as a beginner to the world of Java, Servlets, and JSP, this provided the best introductory place to begin learning these technologies.

More so than any of the o'reilly books, this volume takes you through the necessary introductory concepts. The examples are simple but not trivial, and present material in a way that can be readily absorbed and reused.

This is not a reference book- I feel comfortable setting it aside now that I have digested the contents. But, having been lost in a maze of other reference volumes from Learning Java (too trivial and slow-paced) to JSP Cookbook (too difficult to start) this provides the healthy, learn-quick but absorb-as-well volume I needed.

Rating:
Summary: Good to see Wrox back
Review: Development of the Apache project's Tomcat JSP and Servlet engine continues apace, and again, Wrox has done a good job in swiftly getting a book to market which covers the latest version.

Wrox's earlier book by many of the same authors, 'Professional Apache Tomcat' covered versions 3 and 4. This book no longer contains any material specific to version 3, but has had a major overhaul and concentrates on Tomcat 5, though it's still useful and relevant to administrators working with version 4.1 and up.

Like its predecessor, the book covers the installation and management of Tomcat in great depth on both Unix and Windows. Its Unix coverage is geared towards Linux in favour of any other version of Unix, but in practice there's nothing particularly Linux specific and users of other Unix variants will have no problems following the examples.

As with the previous edition, the first two chapters provide background to the Apache project, J2EE and the evolution of web application technologies from CGI to JSP. Detailed chapters on installation and architecture follow. Only installation of the Tomcat binaries is here though; building Tomcat from source with Ant is not discussed at all (however, Ant is referred to throughout the book, mainly in relation to application building and deployment, and gets an appendix of its own). The architecture description is unchanged from the previous edition, but remains an excellent overview of Tomcat's internal components.

And on to the nuts and bolts. A lot of space is given to the new web-based administration tool (itself a web application handled by Tomcat), but at all points the underlying affects on Tomcat's raw XML configuration files is made clear, so the command line junkies - or those who choose not to enable the Administration Tool at all - are catered for in parallel with the point-and-click brigade. Web application configuration and management is much expanded, now covering Servlet 2.4 descriptors as well as those for 2.3.

Tomcat's HTTP connectors, employed when Tomcat is set up as a stand alone web and application server are described in a single chapter, but new to this book are details of using the SSI and CGI servlets which are new features of Tomcat 4.x and 5.

For non-trivial installations, one would wish to integrate Tomcat with a web server, creating an environment in which the web server delegates dynamic content to Tomcat which otherwise no longer handles HTTP directly. There are a number of protocols available for Tomcat which provide the connection to a web server. As these protocols have stabilised in Tomcat, so the book no longer covers the older, largely deprecated connectors beyond a brief description of each. It then concentrates almost solely on the JK2 implementation of AJP.

This whole area is a lot clearer than it was in the earlier book: a short chapter provides the background and describes the protocols used to connect the web server and Tomcat, followed by a chapter devoted to each of Apache (for both Unix and Windows) and Microsoft's IIS web server using the JK2 connector. I was a little disappointed to find that Sun's web server gets no mention at all, particularly as up-to-date official documentation in relation to it appears to be non-existent. Nonetheless, what's here for Apache and IIS is very good; Apache users get a better deal than their IIS counterparts though - the load balancing and SSL integration sections are far more complete in the IIS chapter.

That completes the first half of the book, and for many uses will provide more than enough information to get a good understanding of Tomcat and a working service. Six more chapters go into great detail about Tomcat's other features. Separate chapters exploring JDBC connectivity, the new JMX features of version 5 and Java class loaders really earns the book its Professional tag. Arguably more useful (in my case at least) are the chapters dedicated to security, clustering for fail-safe operation and embedding Tomcat within an application - absolutely everything is here. The chapter on server load testing proved to be a great help to me just for the inclusion of the use of JMeter, another Apache project which is useful for all manner of web server benchmarking.

Tomcat's documentation is more than adequate for quickly setting up a Tomcat server, but dig much deeper and it quickly becomes difficult to find what you're looking for. Having a book like this with everything to hand makes life a lot easier, and in any case it's worth much more than the official documentation.

Criticisms? I'd like to have seen an appendix or two giving a summary of the main Tomcat configuration files workers2.properties and server.xml; as it is not quite everything is covered and what is spread across different chapters. At the moment I'm working with Sun's web server and Tomcat and it would have been great to have a chapter dedicated to this particular setup, particularly as far as JK2 is concerned.

Wrox had some difficulties last year when its parent company collapsed, but now that Wiley have taken over, it's good to see them back on their feet and continuing to produce books like this, complete with their familiar red covers (...and dodgy author photographs). Highly recommended.

Rating:
Summary: Great Book,easy to follow
Review: Good book, no fluff..just stuff. Explains diff. between 4.0 and 5.0, gives latest cofig and development tech for 5.0

Rating:
Summary: it is worth $25.
Review: I looked through it in 1 day, from the programmer point of view, what I learned is totally worth I paid for the book, I have a clear overall picture of Tomcat, the components ( server, service, host,contexs),directories,especially the class loaders that helps me develop my web applications.
if you are just a programmer and a looking for some systematic inforation of Tomcat, you just need read 3 or chapters,probably this information is publiclly available in tomcat's offical website. this is why I finished in just 1 day.

Rating:
Summary: Important tasks missing
Review: There is a lot of good information in this book, and it's true that it gets into JMX, the web-based manager and admin apps, etc., etc.

But I have some real concerns with this book. Here are four everyday "real world" tasks that a professional really needs to know and that one is hard-pressed to find accurately and succinctly discussioned in this book: (1) JVM memory settings -- in what file to set them; (2) How to pre-compile JSPs so that they are not compiled "on the fly" after deployment (absolutely crucial for the real world); (3) how to define a context.xml file and put it in your app's META-INF directory; (4) How to get an app deployed to the root.

I hope the authors can address these issues in the next edition.

Here's some more detail on these issues:

(1) Memory settings: p. 417: Gives switches for memory optimization, but doesn't say what is the best file in the Tomcat deployment for updating such settings. (The info in "Shared Tomcat Hosting," pp. 392-393, doesn't help for the easy case.) There is no discussion that if you use the Windows Service, the memory settings are set through the "Configure Tomcat" GUI application (and catalina.bat isn't used). A *general* item for "memory settings" is not listed in the index under JVM.

(2) How to pre-compile JSPs: Nothing. A better book would provide a working ant target for this. jspc (and/or org.apache.jasper.JspC) isn't even in the index.

(3) How to use a context.xml file and put it in your web-app's META-INF: Nothing. This is incredibly important because it's how you would define a DataSource without having to meddle with the server.xml file.

(4) How to get an app deployed to the root path. While there is some discussion of the root (e.g., p. 92), I don't see anything that points out the crucial piece of information, which is that the .war must be named ROOT.war (you can deploy another .war to the root, but with some settings it won't get redeployed properly after a fresh startup).

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I also wish the discussion of the JK and JK2 connectors was more complete. The discussion of the internals are interesting, but you would never learn about the no-jk environment variable (crucial for getting Apache to skip JK for certain paths) for JK. And if there is such a feature for JK2 (I don't think there is), you'd never find it here.

In short, I keep this near my desk, but I probably wouldn't recommend it to someone.