Raible Designs

What should we do with Tiles?

There's some discussions taking place on the Struts Developer Mailing List about what to do with Tiles. Tiles is gaining popularity in frameworks other than Struts - i.e. Spring and JSF. Personally, I don't mind that Tiles is buried deep inside struts.jar b/c it's basically the difference between a 500 KB JAR and a 100 KB JAR - and disc space is cheap! However, an advantage of extracting Tiles from Struts is that it then has the opportunity to become friendlier to other web frameworks. I'd even like to see a Sitemesh-like Filter so you could do Sitemesh stuff with Tiles. Or maybe just bundle Sitemesh with Tiles as a kick-ass templating engine.

So the question is: What should we do with it? Should it become a Jakarta Commons project or a Jakarta Project? Or even a java.net project? Tiles Users - we need your feedback!

MySQL Conference - Day 2

JBoss and MySQL
I'm sitting in Mark Fleury's session on MySQL and JBoss Integration. I'll try and record the things I learn in this session. The first thing that Mark mentions is how they own many popular open source projects: Hibernate, Tomcat, etc. - because they employ the lead developers on those projects.

JBoss Numbers
A standard in the market: #1 in development - more than 4 million downloads in last two years alone. A standard for System Integrators: #2 in growth - CRN survey puts JBoss certified consultant at #2 fastest growing certification with large system integrators. A standard in the market: #3 in production - JDJ survey: 70% of users to go Deployment. BZResearch survey. 13% in 2002, 27% in 2003, largest growth of all servers (IBM at 40% and BEA at 34%).

"Federated" Projects
JBoss AS, Hibernate, Tomcat, JBossIDE (Eclipse integration, XDoclet driven development, debugging), JBossCache (distributed data), JGroups (reliable multicast and cluster communication), Nukes (portal and CMS), JBossAOP and Javassist (bytecode manipulation library).

Cache and ORM: Scalability for MySQL
Keep your data in a MySQL instance. Put an ORM (Hibernate) layer on top of it. Replicate the data with cache infrastructure. Cache is King.

Mark is now talking about Hibernate and what it's useful for. I'm guessing that a lot of folks in this session are either interested in JBoss or Hibernate. He's talking about RDBs and what they do well. Next I'm guessing he'll talk about Hibernate and all its features. No need for me to regurgitate that information here - since I suspect a lot you are familiar with Hibernate. If not - what the hell are you waiting for? ;-) If you can't use Hibernate b/c you're standardized on SQL, you should at least use iBATIS. BTW - did you know that BEA's Page Flow demo app is a re-written version of Clinton's JPetstore? If you're standardized on JDBC, you might want to use Spring's JDBC support - which solves many of the problems with JDBC (try/catches, closing connections, etc.).

What is JBossCache?
A transactional replicated cache for JBoss with and without AOP. A cache for frequently accessed elements: Stateful Session Beans, HttpSession. Caches are used in a number of places in JBoss - this one provides a central cache service (MBean interface).

AOP Cache
Java is very dumb - Mark hopes the next OO language we use (in 10 years) is more event-driven (i.e. triggers in Java). This is possible today with AOP. In the example below, Joe's state is automatically transactional and replicated. State replicated, synchronized at transaction commit/rollback.

tree.start(); // kick start tree cache
tree.putObject("/aop/joe", joe); // add aop sanctioned object

tx.begin();
joe.setAge(41);
joe.getAddress().setZip(95124);
tx.commit();

Mark says, "HQL - soon to be EJB 3.0 QL". Interesting quote, eh?

PHP PostNuke - wasn't scalable when they first installed it because it hit the database all the time for security information. The Zend PHP didn't have the notion of global variables - so there wasn't a way to build a cache. According to the PHP guys, MySQL was the cache. JBoss re-wrote it all J2EE and now their server is at 5% utilization with an average of 500 concurrent users. Forums are a port of PHP BB - which is a very nice forum software package IMO. Personally, I'd prefer to use PHP BB over JBoss Nukes since most ISPs offer PHP out-of-the-box. I'm guessing that JBoss Nukes only runs on JBoss. Also, PHP BB is much cleaner and prettier out of the box. I'm a sucker for good looking webapps. ;-)

BTW, Jeremy Zawodny (Yahoo guy) has a number of links that might of interest for this conference. For your convenience, here's the best link: the 2004 MySQL Users Conference blog aggregator.

MySQL Conference - Day 1

I'm sitting in the lobby of the MySQL Conference right now, next to Mr. Eden. He's been blogging this conference like a madman, so there's not reason for me to reproduce. See his posts if you're interested to see what's happening here: Registration and Opening Keynote, MySQL/Innodb Performance and J2EE Performance Tuning Workshop.

I attended the Keynote this morning, which was very informative. I didn't know that MySQL was being used so heavily in large enterprise environments. Moreover, there was an interesting slide that showed a performance comparison between MySQL (4.0.1 Max) and Oracle (9i), IBM DB2 (7.2), SQL Server (2000 SP2), Sybase (12.5). MySQL actually kept in step with Oracle in a 50 million row test - and beat the rest of the competition. Who says MySQL is only for small shops! ;-) I could give you the whole history of MySQL (I wrote it down), but I really don't the point. I'll add it here if I get enough requests. The big theme of the conference is definitely clustering.

After the keynote, I went upstairs and crashed. I was up until 3 a.m. last night fixing Ant support in Eclipse. Now you can run Ant (i.e. test-dao) or individual tests (i.e. LookupDAOTest) in Eclipse or IDEA. As part of this process, I removed the entity includes I was using for Spring's XML files. Now each file is loaded individually in tests and web.xml is configured to load them all. It seems a bit cleaner after making the change. Also, I tried to change to using "mappingJarLocations" for .hbm.xml file mappings. This would enable users to skip the step where they write the .hbm.xml file into applicationContext-hibernate.xml. Unfortunately, this works for everything but running Ant in Eclipse. WTF?! I guess the project's home directory is not the working directory in Eclipse. And finally - a warning: if you want to run JUnit tests in your IDE, you need to run "ant test-dao" (or another one) before running your test. It's not thoroughly tested since I run all my stuff from the command-line, but it's there. I definitely recommend using Ant in your IDE if you really want to use your IDE for everything.

The "Opening Night Reception" is about to begin - time to go get some free booze.

Update: I just got an e-mail on how to fix the Eclipse issue when using "mappingJarLocations". In Eclipse's Ant View right-click on a target, pull up the "Run Ant..." dialog. From there there you can set the "Base Directory:" to something like "${workspace_loc:/appname}". Tried that - doesn't work. :(

My Review of Java Studio Creator (a.k.a. Rave)

I attended a Rave Demo at Sun in Broomfield today. The meeting actually had two parts - the first hour was a marketing schpeel about Sun's Enterprise Java System and the second hour was a demo of Java Studio Creator. The first hour was boring and very marketing esque - they did have an interesting price point though - $100 per employee. This is small business friendly, which is nice to see.

The Rave (a.k.a. Java Studio Creator) Demo was when things got good. Here's my notes from Dan Robert's presentation, followed by my impressions and comments. Dan is the Product Manager for JSC and was seemed to be very in tune with the tools marketing (i.e. all the good stuff from Intellij and Eclipse - and how JBuilder sucks).

What is it?

• New Java Development Tools initiative
  • For the corporate developers who write code, but don't understand all of the complexity of J2EE and just need to get their job done.
• A full fledged Java IDE
  • Visual Design Tools, 2-way editing, Editor, Debugger, Repository Management, and Project Management
  • Cool new Look and Feel
• Complementary to NetBeans and Java Studio
  • Even Enterprise developers can use it for Rapid Prototyping
  • Use Java Studio or any other tool to add persistence layers (heh, this is b/c they think that persistence can only be EJBs ;-))

What does it do?

• Quickly builds web applications that solve time-critical, real world problems
  • Complete web application creation for departments, workgroups and businesses of all sizes
  • Focus on easy to understand, event driven coding model
  • Simplifies access to existing infrastructure
  • All Java-standards based servers, all databases, all Web services, all desktops
  • Their main goal is to do web applications well, they'll catch up with the rest later

Standards-based solution for all developers

• A development solution based on 100% Java standards
• Delivers "Write Once, Run Anywhere"^TM benefits: portable apps, portable developer skillsets
• Quickly solves time-critical app development needs
  • Drag and Drop, rapid visual access to databasess and web services
  • consistent UI look/feel/behavior across all apps

Visual features to speed development

• Palette for widgets, custom graphics, code clips, etc...
• Query Editor

Simplified Access to Existing infrastructure

• Use any JDBC Compliant Database (3.0)
  • Drag in and automatically create DB connections to data-aware components
• Web Service Consumption
  • Easily pull in existing web services from Enterprise wide solutions or business partners

Java Studio Creator Roadmap

• Hammerhead:
  • 2-tier dynamic content web applications based on JSP and JSF with Page Flow design tools
  • Releases: Early Access Spring 04 (today!), FCS Summer 04 (at JavaOne)
• Thresher:
  • Minor Update Release
  • Focuses on Ease of Development and Stability
• Mako
  • Extended Client Support

Download today from http://www.sun.com/jscreator. OS X version will be available shortly after the release (JavaOne).

After the PowerPoint, Dan started into the Demo. The first thing I saw that was cool was that when he clicked on the "Run" button, it actually deploys the app and opens the browser to run it. What you see in the browser looks very similar to what you see in the IDE. The IDE looks very simple. My current client went with me and he remarked that it "looks a lot like Eclipse."

The IDE has lots of palettes, and the UI essentially looks very clean. The pallets can be docked just like in IDEA - which I like. It looks a lot more like a native Windows application than it does like Swing. Here are the palettes it has:

• Server Navigator
  • Data Sources
  • Web Services
  • Deployment Servers Palette
• User Defined
  • JSF Standard Components
  • JSF Validators / Converters
• Property Sheet
• Project Navigator

Dan then dragged a drop down component and a table component onto the page. Secondly, he added a stylesheet and it visually changed the background and fonts on the page. I asked him if there was an imbedded browser. He said they took a look at using Mozilla, but it was too much and apparently one of the "real smart" engineers wrote the embedded browser component from scratch. Dan said it was the same guy who wrote the demo from scratch in 2 minutes at JavaOne last year. The thing I found very cool was that the HTML that is written into the JSP is XHTML - none of this Netscape 4.x support. Fuck Netscape 4.x - I'm glad Sun had the foresight to drop support for it.

After adding the stylesheet, Dan used the Data Sources navigator to grab a table and drag it to the drop-down. Then he did the same for another table and the data grid. Using the Visual SQL Query Builder (which looks a lot like M$ Access) he linked two tables and added a new column from a 2nd table to the grid. He then showed us that JSC has pretty good support for 2-way editing. Edit the code, the visual representation changes. Edit the visual, the code changes. This seems to be a big problem with WYSIWIG editors, especially when it comes to dynamic webapps. It appears that they've done a pretty good job to solve this.

Next he showed us some cool features of the components. For the table, there is an "enable paging" checkbox - and for the drop-down, you can right-click and select "auto-submit on change." He then set a couple of converter types on the drop-down and had to hand-code the event handler for the drop-down. Two lines of very simple code and he was done. The code was simple enough that you could have guessed the syntax. Code completion popped up nicely as well. Apparently the JSF coding style is that each page (JSP) is backed by a Bean that contains different event handlers. The code looked pretty simple and all the data was retrieved via RowSets.

Bill Dudney was there and asked about testing tools (i.e. Cactus or JUnit). Dan's response was that these are usually used by more advanced Java developers and there's talk of it, but nothing has been done yet. Now he pulls up a very cool page navigation creator which he uses to drag and drop buttons and links to point to different pages. Then someone asked about cost - and here's what makes it great. Under $300. They also hope to have lots of add on components for JSF by JavaOne. Unfortunately, there's no tooling for building JSF components in Java Studio Creator. For more information checkout http://developers.sun.com/jscreator.

The main reason I really like Java Studio Creator was that you literally never had to see any JSF code - and you get all of the features I like to use in webapps. Furthermore, I've been training a couple of guys all week on JSPs and using JSTL's SQL tags to do CRUD on a database table. While it's simple stuff, since they've never done web development before, it's a bit advanced. I'm sure their eyes will glaze over tomorrow when I start showing them how to write JUnit Tests, DAOs and how to use Hibernate to CRUD an object. They'll probably fall asleep by the time I show them how to wire the DAOs to Hibernate using Spring. When they saw this demo today - there eyes lit up and they got inspired to do their projects again. It looks easy for them now. All they need is a JDBC 3.0 driver for DB2 and they should be able to rapidly develop webapps with Java Studio Creator. I don't blame them for wanting to use this tool - it greatly simplifies things.

After the meeting, I asked Dan about transactions and if it was possible to use Hibernate instead of the RowSet stuff. He said that since JSC is based on NetBeans, you could probably write a plugin to use Hibernate instead of RowSets. As far as I know, the main reason you'd use Hibernate is for caching - but rowsets probably have that too. I know that the spec lead for JSF is talking to the Spring developers about JSF-Spring integration, so maybe that will be a future option as well.

Another thing that's not currently supported is the use of great technologies like Tiles or Sitemesh. Sitemesh integration would likely be pretty easy - you'd just never see your decorated UI in the IDE. Tiles is definitely something on the roadmap, but they don't have a solution yet. Dan indicated that using "includes" in your JSPs should work just fine - rendering in the IDE as they would in your browser. Good stuff - I hope we start using it at my current project - I think it'll do wonders for productivity. Since it's based on standards (JSF and RowSets) - the generated code looked pretty clean too.

Eclipse Plugins updated for 3.0 M8

At my current client, I'm teaching a class this week on developing Java-based webapps. I'm starting simple with basic JSPs and JSTL's SQL Tags. Later, I plan to teach them how to write JUnit tests, DAOs, Actions, etc. I hope to show them how Hibernate and Spring can reduce the pain of J2EE.

The main problem is that it's kinda tough to teach this stuff to people that have no webapp development experience. How can you tell them Hibernate is soooo much easier, when they've never used JDBC? How can you show them that Spring simplifies things when they've never developed a complicated app?

Anywho, back to the point of this post. As part of the first day, I had the class (actually, there's only 2 students) setup their development environments (JDK, Eclipse and Tomcat). I decided to go with the latest Eclipse 3.0 M8 b/c I'm an upgrade junkie and I firmly believe that it's best to teach the latest and greatest stuff. Because we're using M8, I had to update a bunch of plugins and decided to package it up and release it. So without further ado, I give you Eclipse Plugins 1.1. [Download, Release Notes]

Here's the current list of plugins included in this package:

• XMLBuddy 2.0.5 - XML Editor
• Colorer 0.6.0 - General Syntax Highlighter (JSPs, HTML, CSS, etc.)
• Jalopy 1.0b10 - Source Code Formatter
• Lomboz 3m8.preview3 - JSP Editor
• JSEditor 0.0.4 - JavaScript Editor
• Easy Explorer 1.0.1 - Open Explorer/Finder
• Tomcat Launcher 221 - Run and debug Tomcat
• Spring UI 0.9.5 - Edit Spring's files

NOTE: I updated most of these plugins because older ones didn't work with Eclipse 3.0 M8. I haven't tested all of these, but they are the latest versions (as of yesterday).

I still use Eclipse on Windows, but I sure am getting used to using IDEA on the Mac. Now if I could only figure out some slick ways to pre-program keys-to-code. The Flex guy in NYC last weekend would press one key and a whole block of text would appear. I think that'd be a nice touch for next week's presos in Florida. It'd be cool to write a JUnit Test, DAO Interface, and DAO Implementation in a matter or keystrokes (i.e. one for each method).

Related posts: 1.0 Release.

Moving

We started moving yesterday afternoon - and we're almost done. It sure is convenient simply moving into the house next door. Four good friends showed up around happy hour and helped us out for a couple hours. Kitchen, living room and both bedrooms are done. The only thing that remains is my office, desk, networking, etc. Phone and Internet transition was extremely smooth (Comcast rocks!). It all happened yesterday and we only had about an hour outage on each. I got my wireless network setup quickly and was able to use the neighbors (strong reception upstairs) when it was out. I'm dreading office setup, but I'd better get on it. You'll know when I'm done b/c demo.raibledesigns.com will be back up.

BTW, did you know that Eclipse 3.0 M8 is out? I wonder when MyEclipse will support it?

Write your Java apps in Visual Studio.NET?

Apparently Visual MainWin allows you to write your webapps in C# and .NET and then deploy them to a J2EE server.

Visual MainWin for J2EE enables these organizations to deploy .NET and J2EE applications on a single J2EE infrastructure, eliminating the need to maintain two separate application servers or implement complex interoperability solutions between the .NET and J2EE platforms.

This product certainly won't do anything for me. I've heard that Visual Studio is a great IDE, but if I can't write Java in it - what's the point?

Then again, I'm biased. I have a friend who is a long-time Java developer. Lately, he's been developing in C# because that was the only gig he could get (in Nevada). He says that C# is a piece of sh*t compared to Java.

Update: My friend contacted me to set the record straight. To quote him, "C# is OK, its the .NET framework that sucks ass. The C# syntax is a total ripoff of Java anyways."

Good Ant Tip

Nick has an Ant tip that I can put to good use.

This A little-known Ant feature is the hyphenated target name. If you have a target name that starts with a "-", such as "-test-setup", you will not be able to call that target from the command line. Developers creating utility targets in their build.xml files can use this to avoid confusing other developers with irrelevant support targets.

There are a fair amount of internal targets in AppFuse that don't need to be visible and can't be really be called from the command line. Last time I checked, IDEA and Eclipse both allowed hiding of internal targets - so I rarely see these, but it might be a good idea to make them more explicit. I'll put it on my what-I-can-do-when-I-get-bored list.

AppFuse Refactorings Part II: Spring Integration

I took some time last weekend and refactored AppFuse to use Spring to replace my Factories and Hibernate configuration. It only took me a couple of hours, which says a lot for Spring. I was amazed at how many things just worked. It actually lifted me out of my flu symptoms and made me feel euphoric. Or it could have been the Sudafed. In reality, I only replaced one Factory class (DAOFactory) - a fairly large class that instantiated DAOs using reflection and constructor variable inspection. I was also able to get rid of the ServiceLocator class, the getConnnection() stuff in ActionFilter and the hibernate.cfg.xml file.

The one thing I found when looking at the Petclinic and JPetstore apps was that they used an applicationContext.xml file for unit tests, and a (very similar) one for running the app in a container. To me, this was a warning sign. DRY (Don't Repeat Yourself) is a big reason for using XDoclet and I'm beginning to think that Spring could benefit from a little XDoclet lovin'. Anyway, back to the story.

I wanted to find a way to use the same XML files for testing and in-container execution. As you might know from Part I, AppFuse has 3 different tiers: dao, service and web. To run unit tests for the dao and service layers, I simply load a applicationContext.xml file in my JUnit test's setUp() method and go from there. I saw this in the petclinic app and found that it works pretty well. In the end, I decided to setup different XML files for each layer - applicationContext-hibernate.xml, applicationContext-service.xml and applicationContext.xml for the web layer. The main applicationContext.xml uses entity includes to reference the other two files.

The main pain I found was that the entity includes required different paths for tests vs. running in container. Basically, for tests, I had to use:

<!ENTITY database SYSTEM "applicationContext-database.xml">

While tests, using the ClassPathXmlApplicationContext required:

<!ENTITY database SYSTEM "WEB-INF/applicationContext-database.xml">

Using Ant to do a little replace logic allowed me to jump over this hurdle.

Using this setup, any new DAO definitions are added in src/dao/org/appfuse/persistence/hibernate/applicationContext-hibernate.xml, new Manager definitions (and declarative transaction settings) are be added in /src/service/org/appfuse/service/applicationContext-service.xml. The test-specific applicationContext-database.xml sits in the "test" directory and contains the following:

<bean id="propertyConfigurer" 
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> 
	<property name="location"><value>database.properties</value></property> 
</bean> 

<bean id="dataSource" 
    class="org.springframework.jdbc.datasource.DriverManagerDataSource"> 
	<property name="driverClassName"> 
		<value>${hibernate.connection.driver_class}</value> 
	</property> 
	<property name="url"> 
		<value>${hibernate.connection.url}</value> 
	</property> 
	<property name="username"> 
		<value>${hibernate.connection.username}</value> 
	</property> 
	<property name="password"> 
		<value>${hibernate.connection.password}</value> 
	</property> 
</bean>

While the applicationContext-database.xml for the web is simply:

<bean id="dataSource" class="org.springframework.jndi.JndiObjectFactoryBean">
    <property name="jndiName"><value>jdbc/appfuse</value></property>
</bean>

To integrate Spring with my web layer (Struts), I just used the ContextLoaderListener in my web.xml file. I didn't see any point in bringing yet another JAR file into the mix.

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

Finally, to expose Spring's context to my Struts Actions, I added the following to my BaseAction.java class:

This way, the UserManager implementation can be easier retrieved using:

The best part about the Spring integration in AppFuse is: (IMO) its Hibernate support and how it drastically simplifies my Hibernate DAOs (as if Hibernate wasn't simple enough already). I dig the ability to specify declarative transactions, and this refactoring seems to have reduced the "src" distribution of AppFuse by 2 MB (to 10MB total)! I don't know where this came from since the Spring JAR is almost 1 MB. The appfuse.war is about 500 KB larger, but I can live with that.

Of course, all of this has been checked into CVS if you'd like to take a look.

If you're planning on using Spring...

If you're planning on using Spring with Hibernate, Data Access with the Spring Framework is a must read. This article makes it look easy (and simpler) to use Spring's Hibernate helper classes than the regular Hibernate API. Good stuff - this kind of stuff makes integrating Spring into AppFuse look like fun. Deleting code is always fun. I wonder if MyEclipse will roll in some support for the Spring Framework? What about IDEA? Yeah, I broke down and bought a copy. I could use some "get to know your IDE" tutorials though. One thing I learned from Open Source Programming (and originally from The Pragmatic Programmer) is get to know your IDE. I could certainly use some more expertise on Eclipse and IDEA. I'm going to buy MyEclipse, a good Eclipse book and go read some IDEA documentation. Ambitious plans right before bed - sure sounds good though. Links appreciated - I want to make my IDE-life easier.