Raible Designs

Hibernate vs. iBATIS

There's an interesting thread taking place on the iBATIS User Mailing List. The basic jist of the responses are: Hibernate works well when you control the data model, iBATIS works well when you need to integrate with an existing database. I've said this for a couple years now, and I still believe it. Furthermore, I've found that when working with iBATIS, I tend to know what's going on a lot more. After all, it's just SQL. From all the questions on the AppFuse mailing list, it seems like a lot of Hibernate users are constantly trying to get Hibernate to "work its magic" and handle all their relationships for them.

I wonder if newbies would be better of using iBATIS? Using iBATIS, there isn't a whole lot of magic, and you get full control over the SQL - which would likely be easier to understand. Maybe I should create a "newbie" version of AppFuse - where the frameworks uses are the easiest to learn or most documented. It'd probably be Struts+Spring+iBATIS, or maybe just Spring+iBATIS so I could sell more copies of Spring Live.

[ANN] Equinox 1.3 Released

This release is mainly a bug fix release, but it also adds support for Maven. All of the frameworks used in Equinox, as well as its build/test system is explained in Spring Live. Detailed release notes are below:

- Added missing "validator" property to "userFormController" bean in Spring MVC version.
- Added "redirect" element to success mapping to user list to prevent duplicate post problem.
- Moved "ctx" variable declaration from decorators/default.jsp to taglibs.jsp so it's available to all JSPs.
- Changed any references to UserDAO in UserWebTest.java instances to use UserManager instead (to prevent problems when transactions aren't used).
- Fixed install scripts in extras so they'd work on Windows from the command prompt. Added "fixcrlf" target for users that encounter issues.
- Added installer for Maven in "extras/maven". This can be used to replace the Ant build system.
- Dependent packages upgraded:

• Display Tag 1.0
• Hibernate 2.1.8
• iBATIS 2.0.9b.550
• JPOX 1.1.0-beta-1
• Spring 1.1.4
• Tapestry 3.0.2

Download. For more information about installing the various options, see the README.txt file.

Demos:

• Spring
• JSF
• Struts
• Tapestry
• WebWork

Rather than uploading the different combinations that are possible with Equinox, I figured I'd just wait for requests. So if you'd like things like Tapestry+Spring+JDO, or JSF+Spring+JDBC, let me know and I'll upload a pre-built version of 1.3.

Updating Pro JSP for JSP 2.1

Apress recently contacted me about updating Pro JSP for JSP 2.1. While the fame of having 3 books published is tempting, I think I'm going to have to pass. The Security chapter I wrote could probably use some updates, but I just wrote a Security Chapter for Spring Live - and I don't really feel like writing another. The other chapter, titled "Using Struts, XDoclet, and Other Tools", would be fun (since it's about AppFuse and Struts Resume), but I'd probably try to squeeze way too much into 50 pages.

Maybe I could just %s/Chapter 11 in Pro JSP/Chapter 12 in Spring Live and %s/Chapter 12 in Pro JSP/Chapter 2 in Spring Live and show folks how to use Struts+Spring+Hibernate.

RE: Ruby on Rails Koolaid

David Geary on Ruby on Rails:

Interestingly enough, ROR creates default views for your db tables. Cool. But after I thought about it for a minute, I came to the conclusion that that feature is certainly close to useless: It's nice to get you up and running, and great for seductive demos and articles, but you're going to override at least 100% of the views that ROR generates. And therein lies the rub...

...because views in ROR are a mixture of HTML and Ruby scriplets! We've been there before, of course, in the early days of JSP with HTML mixed with Java scriptlets. No thanks, I'll pass on that giant step backwards.

I've thought about this myself. I think David is right, but only to a certain point. Ruby on Rails (and its scriptlet-ridden views) will work until they get HTML designers in their writing Ruby code. Furthermore, when companies start off-shoring their Ruby development, that's when it gets ugly. JSP scriplets were a disaster because you had HTML developers writing Java code, and using if statements that exceeded the 64K block and such. JSP scriplets are hard to maintain when they're used and abused. I've seen a lot of code (especially the off-shored stuff) that has very ugly and unmaintanable scriplet code. However, using scriptlets in JSPs isn't a bad thing - it's only bad if you're coding business logic and/or, using lots of Java code in them, or having JSPs that are scriplet-only pages.

However, I believe Rails is a bit different. Not only does it enforce MVC from the get-go, but you can't use the views stand-alone (can you?). With JSPs and Servlets, you have the opportunity to use JSPs only - which encourages scriptlets. I do wish that Rails' templates used the ${...} syntax that JSP, Velocity and FreeMarker enjoy - the <% %> syntax brings bad bad thoughts of 1000+ line JSPs.

Oh, and one last thing - for David and Rick (the JSF-is-the-best-thing-since-sliced-bread-duo). At least Rails allows HTML in its view templates. JSF developers don't even get to see HTML anymore - poor guys.

Is Shale ready for primetime?

Is Shale ready for prime-time and use in production applications? David Geary seems to think so:

My consulting job is pretty exciting. I'm using Shale heavily now, especially for wizards. Our application has both static wizards, for creating a new account, for example, and dynamic wizards that are generated from a description of an online-document.

Not only that, but he's going to be talking about it on the No Fluff Just Stuff tour this year.

To start the year, I'm doing three new presentations: "Shale: the next Struts", "Felix: a bag of tricks for JSF", and "Design Patterns: Tales from the server-side". Later on, I'll add two more presentations: in the near term, Killer Web UIs with Tiles and SiteMesh and a little later, a session on Laszlo.

I'm a huge believer in Shale. I have no doubt it's destined for great things, so I'm super-excited about the Shale session.

Now that I've talked about this, I'll probably be accused of caring more about Struts than the other web frameworks I use. In reality, I prefer most of the other frameworks in AppFuse and Equinox to Struts. However, at my current gig we're afraid to move from Struts because we're the only development group that hasn't fallen victim to the Big Blue umbrella. They've tried to make us use WebSphere, but we fought that off and continue to use JBoss. The fear is that if we don't use Struts, and use some lesser-known framework, they'll use that against us. That's why I like Shale - because it might be a way for me to use a more WebWork/JSF-type framework.

Ruby on Rails vs. Struts

Brian McCallister has put together a nice tutorial titled "Rails for Struts-ters (Part 1)". In it, he compares a Struts Action to a Rails ActionController (I think that's the right link).

After looking at the various introductory tutorials for RubyOnRails, a lot of people seem to come away thinking it is a simple CRUD framework -- mostly because of Scaffolding. A common theme seems to be, "well, it looks fast for slapping together a prototype, but when you need control, you it ain't there." I can see why people think that way, after watching the 10-minute video, and the reading the ONLamp tutorial. So here is a stab at a guided tour, using Struts as a point of reference.

Good stuff Brian - can't wait for the next tutorial.

Context Reloading in Tomcat 5.5.7

Today I started using Tomcat 5.5.7 instead of 5.0.28. It was fairly easy to install on my PowerBook - I just had to add the xerces and jmx JARs from the compat package to get things working. The one thing I noticed that's different from Tomcat 5.0.28 is that when I deploy any file, it reloads the context. This can be a pain when I'm just copying JSPs into the webapps directory. I'm willing to admit it could be a problem with my "maven deploy" goal, but since this didn't happen on 5.0.28, I suspect it's the newer version of Tomcat. On 5.0.28, the context was only auto-reloaded when I updated files in the classpath.

The main reason this was frustrating is because we look up a bunch of data from a web service on app startup. The API we're talking to is nice and slow and it takes almost 50 seconds to start our application. Rather than go back to the older version of Tomcat, I wrote some code to serialize all the ServletContext variables to disk, and then check for that file on startup. If the file exists, it deserializes it and puts all the objects back in the ServletContext. Works pretty good and certainly speeds up my development environment. After all this, I'll probably downgrade to 5.0.28. Auto-reloading when classpath files change seems like a better way to go.

[DJUG] JUG Central and BPEL

Last night, I attended Denver's JUG meeting. Below are my notes from the event.

I'm at DJUG listening to Christian and Kris (from Adigio) talk about their experience with using Spring, WebWork, Hibernate, Lucene and SiteMesh to develop JUG Central (I wonder if they knew this name and concept already exists?). JSPs are for the view and MySQL powers the data. This presentation is designed to explain a bit about each framework, and also tips/tricks and pitfalls they experienced when developing the site. They started working on the application in August of last year and deployed it into production in December.

Christian said they weren't going to go into the how for each framework, but Kris has had quite a few slides on SiteMesh so far. I don't blame him - it's a great tool and only a handful of folks (of about 50-60) have heard of it.

SiteMesh Pitfalls: Poor integration with Velocity and some other frameworks. BTW, if you're using Tapestry - Erik Hatcher recently created a JIRA patch with a Tapestry Decorator.

Now Kris is talking about WebWork and since he's a framework junkie, apparently this is going to be the largest part of the presentation. I think one of the nicest parts of WebWork is its auto-type conversion. The only other frameworks I've seen that have this is are JSF and Tapestry. For those that like WebWork and don't like JSF - you might find it disturbing that the WebWork actions (and their tests) in AppFuse are very similar to the JSF managed beans. I would take it as a compliment if I were a WebWork developer.

One nice thing about XWork's action configuration is you can specify a "method" parameter for a particular action. Struts recently added this with its MappingDispatchAction. I'm using this on my current project and it works quite well. Kris really likes WebWork's front-page controller pattern - where you use the <ww:action> tag to execute the action when the page is loaded. Personally, I don't have a problem with going through actions to get to my view templates. Kris finished up his WebWork piece with a plug for AppFuse (thanks!) and WebWork in Action. Congrats to all the authors - wonder if it'll be published before WebWork Live?

Now Christian is talking about Hibernate and its mapping files - and how you can generate your database schema from them - or generate your mapping files from a database. They used XDoclet to generate the mapping files in this particular project.

Hibernate Pitfalls: Think about lazy-loading early. Problems arise when you try to share Hibernate-managed objects across (Hibernate) sessions transparently. Christian mentions that Spring's OpenSessionInViewFilter is a nice way to solve the problem.

Hibernate Tips: Spring simplifies using Hibernate and makes declarative transactions easy. Read Hibernate in Action before starting development. Plan to spend some time learning how to express your data model with Hibernate relationships (one-to-one, one-to-many, many-to-many, etc.).

Christian is now talking about Spring and how it works. After thinking and writing about Spring so much in the last year, I'll just skip over regurgitating this part. ;-) His main recommendation: use real injection instead of appContext.getBean("beanName").

Other tools used: Lucene for searching and POI for indexing Word, Excel and PowerPoint files. Velocity used for templating e-mail messages.

Service-oriented Architecture (SOA) with Business Process Execution Language (BPEL)
Presented by Kevin Geminiuc and Owen Newnan from Policy Studies

This point of this presentation is to communicate what it's like to implement BPEL in a J2EE Container. BPEL is a layer on top of web services. BPEL is a programming language that you can use to program business processes. Allows you to divorce your business process from being human-centric to being document-centric. At Policy Studies, they're using iLog JRules rules engine and Oracle's BPEL implementation.

Benefits:

• Process Visiblity
• Process Agility
• Powerful Language
• Open
• Backed by "the Big Boys" (BEA, Microsoft, IBM)

History: Formerly knows as BPEL4WS, WSBPEL. Open standards based. Orchestrates web services with SOA.

Where we are today: Emerging technology (prepare to bang your head against the wall). .NET and Java products exist, as well as J2EE container integration.

BPEL & WS Standards: BPEL, XPath, WSDL, WS-Addressing, SOAP, XML-Schema, WSIF (Axis), TBD (WS-ReliableMessaging and JSRs 207/208). Note that since BPEL depends on web services (which is not a truly reliable service). Because of this, there are some proprietary extensions available.

At this point, I became bored with the presentation and quit taking notes. While the speakers had good intentions with their knowledge sharing, their delivery needed some work. The code walkthrough and demos were presented with a monotonous and unexcited tone, and a handful of folks left during this part. In summary, BPEL looks like a good way to orchestrate your various business processes. It allows you to call web services, EJBs and whatnot simply by defining their locations and methods in XML.

In his demo, Kevin used Oracle's BPEL Designer, which is an Eclipse plugin that has a nice drag-n-drop editor for managing your BPEL XML files. He also used Oracle's BPEL Process Manager, which seemed to be a lot like Jetspeed - you just drop in the .ear and then deploy your processes to it. The only bad part about the Process Manager is it's administration/deployment interface only runs in IE.

If you're using BPEL in your projects, I'd be interested to hear the tools you're using. As far as open-source BPEL process engines, they mentioned Twister and ActiveBPEL.

AppFuse not for Rookies

Adrian Sutton hits the nail on the head:

...for seasoned veterans who understand (its) technologies well, AppFuse should be a big time saver. I can see a lot of beginners getting into very deep water with it though.

AppFuse can help you get started quickly, but it won't help you really learn how to use the different technologies. Its tutorials are designed to show you how to CRUD a simple object, but that's about it. For learning the different frameworks, that's what books are for. Technical authors put a lot of time and energy into writing. A good way to show your appreciation is to buy their books.

My Recommendations:

• Java Development with Ant - you'll be amazed at how much this book explains AppFuse's build.xml. This book inspired AppFuse (thanks Erik!).
• Pro JSP - AppFuse was the sample app for my chapters in this book. Explains many of the security features in AppFuse.
• Hibernate: A J2EE Developer's Guide or Hibernate in Action.
• Web Frameworks: Struts in Action (or update-to-date with Struts Live), Tapestry in Action, Core JSF.
• Spring Books.

So Struts is Dead, huh?

So most folks think Struts is Dead, huh? I've got news for you folks. Struts has been dead since 2002. For that matter, most Java frameworks have been dead for the last year. Most folks think Struts is dead because there won't be any new and whiz-bang features added in future releases. I'm willing to bet the other Java Web Frameworks won't add any whiz-bang features in the next few years either. Sure, WebWork might get a little XMLHttpRequest lovin' for client-side validation, and Tapestry might get pretty URLs - but both of these are features that these frameworks should've had in the first place. So what's the big deal? At least the Struts Developers have the guts to stand up and say "we're in maintenance mode". Shouldn't all framework developer's be able to say this? It's really quite an accomplishment.

IMO, the only developers that shouldn't be saying this are Tapestry and JSF folks. Both of these teams should be saying - "we're going to make our frameworks easier." If these frameworks are going to be the future of Java web development, there's some work to do. The JSF folks should be saying, "we're going to fix all the stuff that's broken". This "stuff" includes POST for everything, lack of bookmarkability, and bad validation messages (the good news is the validation messages should be fixed in JSF 1.2). I think Tapestry needs some simplification too. In my experience, most Tapestry pages (by design) require 4 files. One for the Java class, one of the HTML template, one for the page specification and one for the i18n keys. This should be easier. It'd like to see two required files (template and Java class) and the others are optional. Maybe annotations could eliminate the page specification? I think there's a lot to be learned from frameworks like Ruby on Rails: default everything, allow overriding.

I think that Shale will be good, but only if it learns from the other MVC frameworks available. If I were on the team, I'd take the good things from all the others: IoC, Interceptors, HTML templates, etc. I wouldn't stop there either - there needs to be good examples of how to integrate it with middle-tier frameworks like Spring, Hivemind and EJBs. Often developers will take examples as recipes - so the more detailed and simple, the better. The Struts developers have quite an opportunity to make something great, let's hope they don't just create another framework.