Spymemcached Optimizations Followup

A couple days ago, Dustin Sallings, the other of the spymemcached Java client for memcached, posted an article on some optimizations done to the library. If you are currently using hibernate-memcached you may want to try out the latest spymemcached RC release.

If you combine the latest spymemcached RC release, with memcached 1.4 and the new binary protocol you should see significant performance increases. As Dustin didn't change anything about the spymemcached API it should be a drop in upgrade for you.

spymemcached Optimizations - Dustin Sallings

hibernate-memcached

Enjoy!

Hibernate-memcached 1.2.1 Released

I released 1.2.1 this morning to fix an NPE that was brought up in the group this morning. The NPE only comes up under an error condition so it really shouldn't be affecting too many people. Either way, it was crappy code and it needed to get fixed.

You can download the 1.2.1 from the site, or just update your maven pom.
http://code.google.com/p/hibernate-memcached/

Enjoy!

Hibernate-memcached 1.2 Released

Earlier this week I released hibernate-memcached 1.2. Hibernate-memcached is a simple library that enables the use of Memcached as a second-level cache in Hibernate.

The 1.2 release updates the Maven dependencies to spymemcached 2.3.1, which includes some bug fixes and reduces the dependencies by one jar (spy.jar is gone). The main purpose of the hibernate-memcached release is to add support for the new binary protocol released with memcached 1.4. Previous versions of memcached only supported the ascii protocol. This has always performed well in it's own right; but the binary protocol reduces CPU compute time and can decrease response time as well.

The hibernate-memcached release also includes a minor tweak to use getMulti in Memcached when DogpilePrevention is enabled. Not a big deal, but someone pointed out an opportunity for it; so I added it.

You can download hibernate-memcached here. Or you can setup your maven project by following these instructions. As always, the source is available via github.

Enjoy!
-Ray Krueger

Follow up to the AbstractHibernateDao

In my writing about the AbstractHibernateDao here I mention that you no longer need to extend HibernateDaoSupport class. You do lose one thing though. Your new AbstractHibernateDao based DAO will now throw HibernateExceptions, not Spring DataAccessExceptions. Now, to me, this isn't the end of the world. In a Hibernate 3.2+ world Hibernate does have a clear exception hierarchy. Not like the old days where there was just "HibernateException". That sucked.

If you do want your DAOs to throw Spring DataAccessExceptions there are two simple things to do.

1. Add the @Repository annotation to your DAO impl.
2. Add a PersistenceExceptionTranslationPostProcessor bean to your Spring setup.

What this does is tell Spring to wrap an interceptor around your DAO bean that handles the exception translation.

Looking at the UserDaoImpl from the past article...

@Repository
public class UserDaoImpl extends AbstractHibernateDao<User> implements UserDao {

    public UserDaoImpl(SessionFactory sessionFactory) {
        super(User.class, sessionFactory);
    }
    ...
}

Then in your Spring application context.xml you simply add one line...

Now, this pattern I present is somewhat old school. There is all this fancy component scanning stuff you can do with the Spring 2.5 XML namespaces. Honestly the amount of voodoo that goes on there freaks me out a bit. You can study that on your own if you'd like. A good place to start is here.

Simple Maven Archetype

I've been doing more and more with Maven lately. We're currently beginning the effort to migrate some of our stuff to Maven at work. A new feature of the archetype plugin was introduced a bit ago to generate java projects from a menu. This is done using mvn archetype:generate. This provides you with a (hideous) menu of options to begin a new project from a template.

The problem I have with this (besides the menu being hideous) is that Maven still defaults the compiler to use source/target settings for java 1.4. Every project I do that uses Java 1.5 needs to have the compiler config settings tweaked to allow the use of 1.5. It is really annoying, so I created my own simple archetype that I can use and uploaded it to github for easy access. http://github.com/raykrueger/simple-archetype/tree/master

This new archetype generates an empty project with compiler settings for 1.5, includes the dev.java.net maven repository and has dependencies for slf4j and junit.

I may move this archetype project in the future into a collection of archetypes. So I can have a simple java one, a webapp one, and whatever else I come up with. If I do move them, I'll update this blog :)

Graeme Rocher's Blog: Groovy and Grails join the Spring family

This is good news I think. Hopefully this gets Groovy and Grails some much needed visibility.

Graeme Rocher's Blog: Groovy and Grails join the Spring family

SpringSource Team Blog: More Weapons for the War on Complexity: SpringSource Acquires Groovy/Grails Leader

Using JRuby and ActiveRecord Migrations to Manage Database Change

Managing change to your application databases is a very common requirement for any development team. The usual approach seems to consist of piling scripts into some "db/changes" folder in your project. This is probably fine for the most part, but when you have multiple databases in multiple environments, managing that across multiple developers can be a problem. If have the usual minimum of three environments (dev, test, prod) you have to remember to apply the right scripts in the right order in each environment. If you are doing iterative development you may be making small database tweaks here and there over a period of a week or two. The difficulty comes in trying to remember what script you applied last and which script you need to apply today.

Following our first instinct of storing sql scripts in source control, let's add another complication into the mix. What if you have to support multiple database engines, say MySQL and Postgres. There will be subtle differences in statements, and database specific properties that need to be set. Managing two sets of scripts becomes a huge pain pretty quickly. Now, as as Java developer, we get to use Hibernate to maintain database portability. Hibernate is a fantastic ORM library, and it comes with tools to generate the DDL needed to create your database from scratch. Unfortunately, it does not include any tools for managing incremental updates to that schema.

The Ruby on Rails folks came up with a solution to the issues above; ActiveRecord Migrations. Migrations are small, incrementally versioned Ruby classes that are designed to bring your database up to date in a controlled fashion. The basic concept is very simple. Store a "version" in the database and maintain a set of Ruby classes that can bring your database up to the latest version. The Ruby classes are numbered using the version they represent and include an "up" and "down" operation. So, let's say we have a current version in the database of "6" and Ruby classes numbered up through "10". When we execute the "migrate" command ActiveRecord will see the current version and see we have scripts that go beyond that and begin to execute their "up" methods in order 7.up, 8.up, 9.up, 10.up. If we wanted to bring our database down to version 8 ActiveRecord would in-turn run the "down" methods. Executing 10.down, 9.down; leaving us at version 8. ActiveRecord Migrations also address our second issue of portability. Your individual migration classes are written in a database agnostic "Domain Specific Language", which allows for the SQL to be generated at runtime for your specific database. Note that you can also execute arbitrary SQL if needed as well.

I intend to show how to do this from the perspective of a Java developer, deploying these changes into a Java deployment environment. This is where JRuby comes in. At my company we already have Java on all of our servers and development machines, but not Ruby (except maybe on dev boxes). Using JRuby allows us to run Ruby on top of the installed JVM without having to worry about installing Ruby. So, let's get crackin' here and do something.

Install JRuby

Download Jruby (1.1.4 as I write this) and extract it somewhere. For me I've dumped it in "~/dev/jruby-1.1.4". Set an environment variable called JRUBY_HOME that points to this location; EX: in .bash_profile: export JRUBY_HOME="~/dev/jruby-1.1.4". Add JRUBY_HOME/bin to your path and you're good to go; EX: in .bash_profile: export PATH=$PATH:$JRUBY_HOME/bin

Install Required Gems

Ruby has a library distribution mechanism called ruby-gems. A gem is a library, every gem has a version and some dependencies. JRuby comes with ruby-gems pre-installed, all you need to do is tell it to install the other libraries you want. We'll need a few of them to get started. Note that I'm going to use mysql via jdbc in this example. You can use the native Ruby drivers for your database of choice, or one of the supported jdbc adapters.

• jruby -S gem install jruby-openssl (we won't use this, but JRuby will complain when installing gems without it)
  
• jruby -S gem install activerecord
  
• jruby -S gem install rake
  
• jruby -S gem install activerecord-jdbcmysql-adapter
  

Since we're using the jdbcmysql adapter we'll need to throw the mysql jdbc driver into our JRUBY_HOME/lib directory.

Configure the Project

Let's start by creating a directory structure to work with. Let's create a folder called "activerecord" with a subfolder named "db" and a subfolder inside "db" named "migrate". Executing "mkdir -p activerecord/db/migrate" will do the trick. In our "activerecord" folder create a file named "database.yml". The .yml file extension means this is a yaml file, Yaml stands for "YAML Ain't Markup Language"; cute right? We're not going to get into yaml much, suffice to say our use of it here is like a properties file. We'll stick to name/value pairs. Our "database.yaml" file will have the following contents...

adapter: jdbc
driver: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost/test
username: root
password: whatever

Note that I am assuming mysql running on the localhost with a database called test. Adjust this file accordingly for whatever your database settings are.

Prepare Your Rakefile

Again, in our "activerecord" folder we're going to create a file named "Rakefile.rb". If you are familiar with Ant then you're familiar with the concept of Rake. Rake is the defacto build tool for Ruby and Rails applications. The Rakefile.rb file is equivalent to the Ant build.xml file, except that it's written in Ruby not XML. As a straight up copy and paste operation, your "Rakefile.rb" will have the following contents...

require "active_record"
require "yaml"

task :default => :usage

task :usage do
  print "Executing \"rake migrate\" will bring the databse up to date\n"
  print "To upgrade/downgrade to a specific version use: \"rake migrate VERSION=X\"\n"
end

task :migrate => :configure do
  ActiveRecord::Migrator.migrate("db/migrate", ENV["VERSION"] ? ENV["VERSION"].to_i : nil )
end

task :configure do
  ActiveRecord::Base.establish_connection(YAML::load(File.open("database.yml")))
  ActiveRecord::Base.logger = Logger.new(File.open('migrate.log', 'a'))
end

If you look at it this file you can see how it is similar to an Ant build.xml file. The "task" blocks (the block is denoted by the do/end) are like "targets" in Ant. Here we've got a task named "migrate" that depends on the "environment" task. The "environment" task sets up our database connection using our Yaml file, and configures a log file to write to. Our migrate task simply tells the ActiveRecord Migrator where the classes are and optionally a specific VERSION to move to. Specifying a version is commonly used for rolling back to some point in the past.

Write Your First Migration

I'll put together the migration classes necessary to build a "user" table, and a "messages" table, with a cross-reference table joining users to messages in a one-to-many relationship. I'll do this in small steps so we can see it as a serious of migration steps. Let's start right off with the User table. In the "db/migrate" folder create a file named "001_create_user_table.rb". The name of this file is important and significant. The first part represents our version, in this case "1". Everything after that is actually ruby standard class file naming. We're defining a class named "CreateUserTable", which therefore means it should be in a file named "create_user_table". Why the swich from camel to case to underscores? I haven't a clue...

class CreateUserTable < ActiveRecord::Migration
def self.up
  create_table :user do |t|
  t.string :username, :null => false, :limit => 15
  t.string :fullname, :null => false, :limit => 30
end
end

def self.down
  drop_table :user
end
end

The migration above is a Class that extends ActiveRecord Migration, it defines two instances methods named "up" and "down". The "up" method calls a method (on Migration) called create_table and passes it a block. When create_table executes the block it will pass it a "TableDefnition" instance, which we named "T". We then call the "string" method on the TableDefinition and pass it "symbols" stating the name and a map (the comma-delimited name/value pairs) containing the options for the column. The "down" method just calls the "drop_table" method. If I have to explain what that does, you're in way over your head :)

OK, let's try it! Bring open a terminal to your "db" folder and run "jruby -S rake migrate". The "-S" I keep using tells Jruby to execute one of command from JRUBY_HOME/bin. If all goes well you should see the following output:

(in C:/source/activerecord)
== 1 CreateUserTable: migrating ===============================================
-- create_table(:user)
-> 0.0031s
-> 0 rows
== 1 CreateUserTable: migrated (0.0036s) ======================================

Once we've executed this migration we should be able to see our new table in mysql:

mysql> show tables;
+-------------------+
| Tables_in_test    |
+-------------------+
| schema_migrations |
| user              |
+-------------------+

The user table is our new table and the schema_migrations table was created by ActiveRecord to track the current version essentially. ActiveRecord actually keeps track of all the migrations applied to it as of ActiveRecord 2.0. If you see a schema_versions, table then you weren't following along very well as you have a really old version of ActiveRecord :)

Migrating the Rest of the Way

W'e're now going to push through our last migration; that message table I mentioned. First create file in "db/migrate" named "002_create_message_table.rb". That file will have the following:

class CreateMessageTable < ActiveRecord::Migration
def self.up
  create_table :message do |t|
  t.references :user
  t.text :message
end
end

def self.down
  drop_table :message
end
end

The new feature we're seeing here in the message table migration is the use of "t.references". Our create_table operation will always create an "id" column for us to represent the surrogate primary key for our table. In doing so ActiveRecord can follow some conventions here. Using "t.references" tells ActiveRecord to setup a foreign key to our user table id column. After that we tell ActiveRecord to create a text (clob) column named "message".

We're ready to execute our next migration. Again, ActiveRecord will look at the versions on our scripts we have provided and compare that with the schema_migrations table to decide what needs executing. Once that decision is made it will walk through them in order...

Executing "jruby -S rake migrate" should give the following output...

(in C:/source/dbupdate/activerecord)
== 2 CreateMessageTable: migrating ============================================
-- create_table(:message)
-> 0.0061s
-> 0 rows
== 2 CreateMessageTable: migrated (0.0085s) ===================================

Now let's have a look at what's in mysql...

mysql> show tables;
+-------------------+
| Tables_in_test    |
+-------------------+
| message           |
| schema_migrations |
| user              |
+-------------------+

We should also see that our schema has been migrated up to version 2 by looking at our schema_migrations table...

mysql> select * from schema_migrations;
+---------+
| version |
+---------+
| 1       |
| 2       |
+---------+
2 rows in set (0.00 sec)

Downgrading

Our Rakefile.rb was looking for a VERSION parameter to read from to force our migration to go to a specific version. Generally speaking you use that to downgrade to a prior version for whatever reason. Let's try that now, execute the "jruby -S rake migrate VERSION=1" command to tell ActiveRecord to step us back to version 1. You should get the following...

== 2 CreateMessageTable: reverting ============================================
-- drop_table(:message)
-> 0.0044s
-> 0 rows
== 2 CreateMessageTable: reverted (0.0067s) ===================================

As you might have guessed ActiveRecord executed our CreateMessageTable.down method, at which point we executed the drop_table method to undo that version. And, again, if we look at the "schema_migrations" table we'll see that it too has been stepped down to version 1.

mysql> select * from schema_migrations;
+---------+
| version |
+---------+
| 1       |
+---------+
1 row in set (0.00 sec)

The Right Tool for the Job

By trade, I am a Java guy. I dabble in Groovy and Ruby and fun stuff like that, but still, I'm paid to be a Java guy. Sometimes you have to know when to use the right tool for the job. Even if you're not familiar with Ruby you really don't need to think of it that way. Ruby is used to provide you with the domain specific language used to handle portable database migrations. You don't need to concern yourself with learning the full extent of the Ruby libraries, or all of the fancy dynamic language features. You just need to pay attention to what values you're passing to these methods and in some cases (maps/hashes) their funky syntax. Honestly I've been looking at doing an article like this for a long time. I'm glad I finally sat down and right it. Hopefully this helps some folks see the power in stepping out from behind our Java comfort zone.

References

• http://rails.aizatto.com/2007/05/27/activerecord-migrations-without-rails/
  
• http://api.rubyonrails.org/classes/ActiveRecord/Migration.html
  
• http://www.scribd.com/doc/1083725/Migrations-in-Rails-20

If you'd like to see what a large sampling of ActiveRecord migrations take a look at the ones in Trisano.

Hibernate-memcached 1.0 released into the wild!

This evening I decided it was time to release hibernate-memcached 1.0. It has all the features I intended for it to have and I haven't seen any problems come up with it at all, so it must be time. Please, spend some time checking it out, even if you don't think you're going to use it right now. I'd really love to get some feedback and see if there is anything folks would like to see it do in a future release.

If you have any questions or comments please drop a line here or even use the hibernate-memcached Google group.

So, what next?

Hibernate 3.3 and Hibernate-memcached

I spent some time looking over the new Cache SPI released in Hibernate 3.3.0.GA. Definitely a much more in-depth API compared to the old CacheProvider/Cache interfaces. Following the new interfaces (RegionFactory, Region) you can be much more aware as to your specific responsibilities in the caching system.

I have tested that hibernate-memcached remains compatible with hibernate-3.3.0 and everything looks fine. I am going to hold off on implementing a RegionFactory/Region based implementation for now and do that as a post 1.0 release. It will require some refactoring to the current code base to get it to play nice with both APIs (I'd like to stay compatible with 3.2 for a while).

So, look forward to a hibernate-memcached 1.0 release tonight, or maybe tomorrow.

P.S. Hello China! According to Google analytics, a link from javaeye.com is generating 250+ hits a day to the hibernate-memcached project site right now.

Hibernate-memcached 1.0-RC1 Released

This morning I've released hibernate-memcached 1.0-RC1. This release contains the new Dogpile prevention feature as well as some minor refactoring. If you're using hibernate-memcached, or are even slightly interested in testing out using memcached in combination with hibernate as a second-level cache, you should check this version out.

If you have questions or problems please visit the hibernate-memcached google group.

Dogpile Prevention for Hibernate-memcached

I posted on the hibernate-memcached project that I was going to release a 1.0-RC1 soon. I will, but first I want to implement one more feature that I think people might like; Dogpile Prevention.

If you're only running 2 or 3 instances of your application this really isn't a problem. If you're running 42 instances there is the risk of a "dogpile". If a frequently used item drops from the cache after it's expiration time comes up you run the risk of many instances of your application working concurrently to restore the cached data. Each instance overwriting the other instances attempt to update the cache until everyone sees the data is no longer missing. Other caching systems attempt to remedy this with locking. That's a really bad thing most of the time for scaling as you'd never want to have all the instances of your application synchronized on what one of them is doing.

To remedy this in hibernate-memcached I will follow the patterns mentioned in the article above. This new feature will go in as a configurable option that is, by default, turned off. I plan to make it configurable per cache-region so enabling it would look like hibernate.memcached..dogpile.prevention=true. There is a slight bit of overhead to this is why it won't be on by default. I may make it configurable at the global level as well with something like hibernate.memcached.dogpile.prevention=true.

Once I get this in and tested I plan to release a 1.0-RC1 version of hibernate-memcached.

Jt - Java Pattern Oriented Framework

Folks actually built an application framework dedicated directly to GOF software patterns. I'm pretty sure this absolutely what patterns were never meant to be used for. Software design patterns are meant to be applied to specific scenarios were they can be proven to be useful. Not as some golden hammer that when repeatedly bashed into your project will somehow produce the holy grail.

Open Source Application Monitoring from Orbitz

This week Orbitz announced that our internal monitoring api "ERMA" is now open source. ERMA (Extremely Reusable Monitoring API), as a framework for monitoring the health of simple applications or large distributed applications alike. The framework is based on Aspect Orient Programming and Complex Event Processing.

I've had the pleasure of using ERMA at Orbitz on many applications and projects. I've also had the fun of contributing code to the ERMA code base even though it didn't really belong to my team. Sort of an "internalized open-source" model if you will, it's how things get done at Orbitz.

I am a member of the core team that will continue to develop ERMA and expand it into new areas (such as ERMArb). We've got a lot of planning to do to see where we want to go with it. ERMA has been extremely useful at Orbitz and I can't wait to see what others do with it.

Read more about it...
at InfoQ
at CNET

Hibernate-memcached 0.6 released

I've released version 0.6 of the hibernate-memcached integration. Mainly this was to fix the "nextTimestamp" stuff that hibernate uses for query caching. Apparently that value needs to be "course grained" when using a distributed cache.
hibernate-memcached at Googlecode

Grails 1.0.3 Released

Graeme Rocher announced the release of Grails 1.0.3 this morning. Great news, time to upgrade my apps!
Read Graeme's post

Introducing hibernate-memcached

Some of you may, or may not (care), know I am a huge fan of memcached. Its combination of simplicity, elegance and performance make it fantastic choice for any real caching solution.

I've recently begun work on implementing a bridge for using memcached as a second-level cache for hibernate. The project is hosted at googlecode right now, and the code is currently available in the googlecode hosted subversion repositories. In the future I'll probably move it over to github, but subversion is much more accessible to the public at large still.

Adding hibernate-memcached to your hibernate based application is as simple as adding hibernate-memcached.jar, memcached.jar, and spy.jar to your classpath. This can also be done using Maven.

Enabling the hibernate-memcached cache is simple as adding two properties to your hibernate config.

hibernate.cache.provider_class=com.googlecode.hibernate.memcached.MemcachedCacheProvider
hibernate.memcached.servers=server1:11211 server2:11211


Property #1 tells Hibrnate to use the MemcachedCacheProvider. Property #2 tells the MemcachedClient in use what servers to use for the cache. It really is as simple as that.

There are many other configuration properties available to configure things like the default and per-region cache times, operation timeout, hash algorithm to use, and what key strategy to use.

The hibernate-memcached cache is working great for both individual entity caching and query caching. I currently have a lot of work to do around getting documentation up on the googlecode site. It is ready to play with and easy to setup, if anyone out there has the time to check out; please do! If you run into any questions or problems you can post them on the hibernate-memached google group, or open an issue at googlecode.

Spring Security 2.0 Released

Spring Security 2.0 has been released into the wild. Tons of great new features, including OpenId Support!

http://www.springframework.org/node/627
http://forum.springframework.org/showthread.php?t=52640
http://www.nabble.com/-ANN--Spring-Security-2.0.0-Released-to16701081.html

Hibernate and Memcached

As I mentioned at the end of my last post, Cache Everything, I am working on building a library to use memcached from Hibernate as a second level cache. That project is hibernate-memcached and its in it's infancy over at googlecode.

The Hibernate second level cache is used to cache items between session invocations. Hibernate always uses it's session as a first level cache, but if you want to avoid database hits between sessions you need a second level cache. If you want these caches to stay in synch between several instances of your application, you need a distributed second level cache.

Memcached is a fantastically fast distributed cache, so why not use that? Once I build a jar of the hibernate-memcached project you'll be able to include it in your application and tell Hibernate to use it. Telling Hibernate to use it means adding the cache_provider property to your hibernate.cfg.xml, or your Spring LocalSessionFactoryBean if you're using that. The hiberante.cfg.xml looks like this...

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.cache.provider_class">com.googlecode.hibernate.memcached.MemcachedCacheProvider</property>
        <mapping class="com.yadda.yadda.Something"/>
    </session-factory>
</hibernate-configuration>

Then, in your mappings you tell Hibernate that you want instances of your persistent objects to be cached, or collections from relation ships to be cached. Once Hibernate knows what you want cached you can watch it pump stuff into memcached, which is good clean geeky fun. Fire up memcahed (on windows or linux) using the -vv command line option to make it run "very verbose". You can see it storing and responding for each operation taken.

You can play with the code straight out of subversion at google code. It will actually work and cache stuff, but it is currently hardcoded to look only at localhost:11211 for a memcached instance. I'll get around to making it configurable. To build the code you'll need Maven2. I highly recommend using Don Brown's no-suck port of maven2 actually.

More to come...

Cache Everything

So I'm working on this Web Service project and its time to consider scalability. Which means its time to setup memcached. If you haven't looked at using memcached, you should.

Memcached is a totally stupid-simple distributed memory object cache. It's this super tiny application that slices off a chunk of RAM and listens on a port. Yeah, that's about it :)

It gets cool to talk about when you start talking about making it "distributed". When you start talking about "Distributed Caches" people start thinking about Coherence and other hugely complicated and hugely expensive enterprise applications. It really dosen't have to be so hard.

Here's what you do. Get a couple cheap boxes with one or two gigs of ram in them. Install the Linux flavor of your choise. Install memcached and run it with "memcached -d -m 1024". This will start memcached on it's default port (11211) and allocate 1gb of ram to the cache. If you do this on three boxes, you now have a 3gb distributed cache.

There are client libraries available for most popular languages. If you're using Java I'd highly recommend using spymemcached from Dustin Sallings.

So you give the clients a list of servers to connect to and they will basically treat that big distributed cache you created as a huge hashtable. Each get/set operation has a string key that is hashed and used to decide what "partition" of the cache to read/write to. If an instance goes down the client just begins distributing reads/writes to the other instances until the missing member comes back.

Using any of the client libraries, in just about any language, your usage looks like this:

• Check the cache for your object.


• If your object is not null, return the object.


• Otherwise, read the object from the database or what have you.


• Put the object in the cache.


• Return the object.

Memcached uses a very light and fast binary protocol which makes it usable by just about any language. There are pre-built packages in apt if you're using Ubuntu, you can easily build it from source for just about any other *nux flavor. There's even a windows port. I've only used that for dev at this point though.

I'm working on writing a second level cache for hibernate that uses memcached. It is super simple, but I just started work on it last night (seriously). Check it out if you want. I plan to work on it over the next few nights and get it ready for prime time :)

Video: Rolling out Web Services the Right Way with Spring-WS

http://www.springframework.org/node/544

Posted two days ago at Springframework.org, a video about the Spring Web Services project. The video is a recording of Arjen Poutsma of Interface21 at the Spring Experience conference in December 2006.

We have chosen Spring-WS for a project my team is starting at work. We will definitely sit down and watch this. I have no idea if the video is good or not, I haven't watched it yet. Arjen is a really smart dude, so I'd imagine there's some good information here.