I had the good fortune of attending eRubycon a few weekends ago and I can honestly say that I've never seen more value in a conference. My previous rant on how NFJS is letting the level of their speakers slip was only more evident in the 3 days spent at eRubycon. Neal Ford, Stu Halloway, Joe O'Brien, Jim Weirich, Charles Nutter and many others contributed valuable sessions that left me wishing the conference went on for a few more days.
The great thing about eRubycon was that it very rarely focused on what is typically the gateway drug in adopting Ruby, the Ruby on Rails framework. Rails is a multitude of patterns and practices that are worthwhile regardless of your current language, but it sometimes overshadows the true core of "beautiful code", Ruby.
The conference left me wanting to learn more about Ruby and to generally spend more of my time at work adopting Ruby. The challenge I (and many others have) is to do this while still meeting client requirements. Brian Sam-Bodden gave a great visual representation of how a Java project can incrementally adopt Ruby as a build language, scripting language, and testing framework. I missed half his presentation as I was so focused on pulling in buildr and some other utilities into my current project.
I think the two biggest topics covered though were essence vs ceremony and testing your application versus testing your framework. Stu Halloway gave a great keynote on essence vs ceremony and while his Java examples were typically very dated, his points remained true. Java (and C# by extension) force you to type crap that is just clutter or ceremony. The less ceremony in our applications, the easier they are to test, maintain, and actually produce on time. I don't recall who initially mentioned the difference between testing your framework and testing your application, but it was a point that haunted me all weekend. It's a very gray line typically between the two and one that can drastically impact a project schedule. Unfortunately, there is no easy answer to this one, so be sure to be cognizant of it when writing your unit, functional, and integration tests.
In summary, eRubycon far exceeded my expectations for a conference under $300. Speakers, content, hallway discussions, and after hours scotch induced discussions were all way above what I had hoped. Keep it up Joe, I'll see you there next year.
Saturday, August 16, 2008
Sunday, July 27, 2008
NFJS - Day 3
Spring Talks by Keith Donald
Spring has largely been my focus for the last few years so I was happy to see one of the Spring Source crew stepping up at NFJS. Keith Donald is the lead of almost all Spring web related technologies and he tends to give a very down to earth, code centric presentation so I devoted all of my final day to his talks.
Someone in the audience asked Keith if he missed the common XML file that shows exactly how all your beans are wired when you move to annotation driven POJOs and that question is an important one. I've recently become much more comfortable with developing Spring applications due to the Spring Facet in IntelliJ. Moving to annotations tends to make me question exactly which resource or component is plumbed in to fill a dependency. Keith mentioned that an emerging best practice is to use annotations for self describing application dependencies, XML for infrastructure concerns. He also gave a soft sell for Spring IDE to show a nice dependency graph regardless of annotations or XML.
Spring 2.5 is downright giddy with it's extensive use of annotations and it didn't really dawn on me until Keith's talk that it might be the better way to go in some scenarios. I've traditionally balked a little bit at the extensive use of annotations as it feels very invasive to the code at hand, especially when the annotations are Spring specific. More importantly, swapping out facilities for testing purposes is not trivial when you are doing component scanning and autowiring with annotations. I think Keith articulates an appropriate scenario for use though. Swapping out mock classes via XML is not a benefit that is needed as much for application dependencies as it is one that is needed for infrastructure (data access, email service, file reader, etc...). Go nuts with annotations at the app level, but use a good editor and keep the XML where it belongs for infrastructure pieces.
Keith spent a good amount of time in all of his talks using an IDE focused on Spring MVC controllers. The thing that stood out to me was how Spring web controllers are truly just POJOWAs now (I know that's not a term that will stick but a distinction needs to be made between POJOs and POJOs with annotations). This means that you will rarely see HttpServletRequest or ModelAndView type classes in these POJOs. What's the benefit here? You don't have to waste many of your test cycles mocking up the container objects. Wanna test your login method on the controller? Send in a User object and a String password and then validate whether you are getting a success or error redirect back. Very simple, and anything that we can do to lower the barrier of entry to good testing is well worth it.
Keith demonstrated another key change in coding Spring apps is the impact that Rails has had on the Spring community. The focus has shifted in Spring 2.5 to more sensible defaults and a true convention over configuration model. Controllers in Spring web apps now mimic Rails controllers in URL and request parameter resolution. Additionally, there are a set of special parameter types that are automagically injected. An arg of type Principal will be supplied by the container if the user is already logged in. Very cool.
One final note on the Spring web side. Why do we have another javascript framework? If you have improvements to make to DOJO, please just contribute them to DOJO. Don't create an abstraction layer over DOJO that does what you need. We have finally whittled the .js framework comparison down to a handful in my mind (prototype/scriptaculous, dojo, jquery, yui, and ext). Don't lead us back in the other direction.
Conference conclusion
NFJS again provided some immediate exposure to worthy technologies and processes. I was able to touch base with a lot of people in the Java community that I hadn't seen in some time and I feel like I have more tools in my belt than when the conference started. A special note to the organizers though. If the prices go up again next year while the number of conferences goes up as well, then you won't see me there for the first time in 4 years. It was evident to me this year that the conference is not the value that it was 2 and 3 years ago. If the trend continues, I'd rather spend my training dollars on codemash, erubycon, and books.
Spring has largely been my focus for the last few years so I was happy to see one of the Spring Source crew stepping up at NFJS. Keith Donald is the lead of almost all Spring web related technologies and he tends to give a very down to earth, code centric presentation so I devoted all of my final day to his talks.
Someone in the audience asked Keith if he missed the common XML file that shows exactly how all your beans are wired when you move to annotation driven POJOs and that question is an important one. I've recently become much more comfortable with developing Spring applications due to the Spring Facet in IntelliJ. Moving to annotations tends to make me question exactly which resource or component is plumbed in to fill a dependency. Keith mentioned that an emerging best practice is to use annotations for self describing application dependencies, XML for infrastructure concerns. He also gave a soft sell for Spring IDE to show a nice dependency graph regardless of annotations or XML.
Spring 2.5 is downright giddy with it's extensive use of annotations and it didn't really dawn on me until Keith's talk that it might be the better way to go in some scenarios. I've traditionally balked a little bit at the extensive use of annotations as it feels very invasive to the code at hand, especially when the annotations are Spring specific. More importantly, swapping out facilities for testing purposes is not trivial when you are doing component scanning and autowiring with annotations. I think Keith articulates an appropriate scenario for use though. Swapping out mock classes via XML is not a benefit that is needed as much for application dependencies as it is one that is needed for infrastructure (data access, email service, file reader, etc...). Go nuts with annotations at the app level, but use a good editor and keep the XML where it belongs for infrastructure pieces.
Keith spent a good amount of time in all of his talks using an IDE focused on Spring MVC controllers. The thing that stood out to me was how Spring web controllers are truly just POJOWAs now (I know that's not a term that will stick but a distinction needs to be made between POJOs and POJOs with annotations). This means that you will rarely see HttpServletRequest or ModelAndView type classes in these POJOs. What's the benefit here? You don't have to waste many of your test cycles mocking up the container objects. Wanna test your login method on the controller? Send in a User object and a String password and then validate whether you are getting a success or error redirect back. Very simple, and anything that we can do to lower the barrier of entry to good testing is well worth it.
Keith demonstrated another key change in coding Spring apps is the impact that Rails has had on the Spring community. The focus has shifted in Spring 2.5 to more sensible defaults and a true convention over configuration model. Controllers in Spring web apps now mimic Rails controllers in URL and request parameter resolution. Additionally, there are a set of special parameter types that are automagically injected. An arg of type Principal will be supplied by the container if the user is already logged in. Very cool.
One final note on the Spring web side. Why do we have another javascript framework? If you have improvements to make to DOJO, please just contribute them to DOJO. Don't create an abstraction layer over DOJO that does what you need. We have finally whittled the .js framework comparison down to a handful in my mind (prototype/scriptaculous, dojo, jquery, yui, and ext). Don't lead us back in the other direction.
Conference conclusion
NFJS again provided some immediate exposure to worthy technologies and processes. I was able to touch base with a lot of people in the Java community that I hadn't seen in some time and I feel like I have more tools in my belt than when the conference started. A special note to the organizers though. If the prices go up again next year while the number of conferences goes up as well, then you won't see me there for the first time in 4 years. It was evident to me this year that the conference is not the value that it was 2 and 3 years ago. If the trend continues, I'd rather spend my training dollars on codemash, erubycon, and books.
Saturday, July 26, 2008
NFJS - Day 2
Stu Halloway's Refactoring Javascript was a topic I did not expect to see at NFJS this year, but I walked away truly impressed. Stu presented a totally different mindset on developing, testing and refactoring javascript code. The gist of it is to use a mock browser that will allow you to run tests against your javascript code in an automated environment. Here is the mock browser but it is still in a beta state so expect to have to bend it to your will. Stu made extensive use of JSSpec for writing BDD specs against an existing javascript framework (livepipe). It was truly telling in the presentation that the first hour was spent trying to get a solid safety net of tests up and passing before we even began thinking about refactoring. Stuart accurately identified this as the norm when refactoring legacy code and it lines up directly with my experience as well. Refactoring can't be done w/o that safety net. When we finally did get around to refactoring, Stuart boiled it down to four areas:
Extract and Shorten
- If your method does more than one thing it does too much
- Keep method size to around 5 - 7 lines
Reduce Clutter
- Nix out of scope variables
- Keep the effort to duplicate a method greater than the effort to understand it
Choose Good Names
- Probably the most difficult of the refactorings
- Definitely the refactoring most in need of pair programming
Use Existing Libraries
- If you are typing document.getElementById then punch yourself first and download prototype.js second.
The talk was extremely hands on and valuable and made me wish I had a bucket of crappy javascript to go back to on Monday. Other things mentioned included another mock browser env: Crosscheck. Stu also mentioned a lack of code coverage tools for Javascript, but I found one during his talk. One last thing, he mentioned a very important refactoring anti pattern. Mirror methods (get and set on cookie) used in each others tests. If you are testing the get method on a cookie object don't explicitly use the mirror method (set). Instead, roll it by hand as a bug in code shared by these methods could offset each other in the test execution.
The second talk I went to was Stu's GIT talk. I've been looking into GIT for a little while and Stu gave a good gentle intro into it by basically walking through scenarios at a command prompt for 90 minutes. That format doesn't necessarily translate to a blog so here are some highlights:
- When using GIT, think less in terms of verbs
- GIT is not SVN++
- It's crazy fast. Branching and tagging for instance are instantaneous
- The entire source history is in every copy of the repo
- It doesn't store deltas, it stores the begin and end and calculates the deltas.
- You are forced to tell git what you are committing. It's not tracking it like SVN
- GIT encourages agility. You may not know what makes a package/release/hunk of functionality until sometime in the future. Additionally, you can stash your current task deliverables, go do something else, and come back to them later.
- Bisecting allows you to do a binary search through releases of code to identify the release that caused a bug. Kick ass.
Metaprogramming in Groovy by Brian Sam-Bodden was the third session I attended. BSB did a good job of going over the major metaprogramming techniques in Groovy. Additionally he had enough examples of Groovy code with TextMate that forced my hand to download it and see if it will cure what ails me with IntelliJ in dealing with Rails and Grails. Stream of conscience notes on metaprogramming with Groovy:
- Much simpler than using dynamic proxies in Java
- Similar to ruby it allows on the fly evaluation of code via evaluate
- Duck typing like ruby with respondsTo
- See yesterday's bits on methodMissing and invokeMethod
- obj."$methodToCall"() is valid Groovy code that will try to call the contents of methodToCall as a method on obj. In my opinion that code is utterly disgusting.
Also, the inevitable Ruby v Groovy topic came up as it did at lunch with me and a few others. There still seem to be zealots on both sides and I wish for the life of me they would just shut up.
My 2 cents are this. Use whatever makes most sense for your environment and team. At my consulting company, that is Ruby b/c I have a lot of .NET fellas that I would like to roll into and out of projects whether it is deployed on MRI, JVM, or DLR. The differences at my admittedly noob perspective are few and far between with the two languages. If it was a room full of Java developers, Groovy might make more sense because it is an easier transition for Java heads. I don't care what you choose for your environment, just quit bitching about the other side.
EJB3 Testing by Joseph Nusairat was my final session of the day. Joseph covered a wealth of testing frameworks in a very code centric presentation. The session was very interactive and covered some cool mocking techniques outside of the realm of EJB3, like dealing with mocking static methods. My attention span was slipping this late in the day, but here is a set of highlights:
- Easymock provides the typical set expectations, record and playback functionality. It is still probably the most proven, well documented, and easy to learn of the mock frameworks.
- JMockIt is a relatively new player with some cool support for AOP and Hibernate. Please notice the IT at the end of the name. JMock is a different framework. Unlike EasyMock and JMock, JMockIt is a very small and straightforward API that can be used to test methods w/o dynamic proxies or cglib.
- EJB3Unit has some very cool facilities. It provides an in memory database out of the box (HSQLDB), uses CSV files for populating the data and provides mocks of almost everything that you would need in an EJB 3 bean. If you have to use EJB3, this framework seems like a valid contender.
- Embedded JBoss is the last one covered and it seems like a good fit for mocking out an entire container when necessary and using JBoss.
- Mocking for unit testing, other tools still necessary for integration and functional tests.
I'm tired. See you tomorrow.
Extract and Shorten
- If your method does more than one thing it does too much
- Keep method size to around 5 - 7 lines
Reduce Clutter
- Nix out of scope variables
- Keep the effort to duplicate a method greater than the effort to understand it
Choose Good Names
- Probably the most difficult of the refactorings
- Definitely the refactoring most in need of pair programming
Use Existing Libraries
- If you are typing document.getElementById then punch yourself first and download prototype.js second.
The talk was extremely hands on and valuable and made me wish I had a bucket of crappy javascript to go back to on Monday. Other things mentioned included another mock browser env: Crosscheck. Stu also mentioned a lack of code coverage tools for Javascript, but I found one during his talk. One last thing, he mentioned a very important refactoring anti pattern. Mirror methods (get and set on cookie) used in each others tests. If you are testing the get method on a cookie object don't explicitly use the mirror method (set). Instead, roll it by hand as a bug in code shared by these methods could offset each other in the test execution.
The second talk I went to was Stu's GIT talk. I've been looking into GIT for a little while and Stu gave a good gentle intro into it by basically walking through scenarios at a command prompt for 90 minutes. That format doesn't necessarily translate to a blog so here are some highlights:
- When using GIT, think less in terms of verbs
- GIT is not SVN++
- It's crazy fast. Branching and tagging for instance are instantaneous
- The entire source history is in every copy of the repo
- It doesn't store deltas, it stores the begin and end and calculates the deltas.
- You are forced to tell git what you are committing. It's not tracking it like SVN
- GIT encourages agility. You may not know what makes a package/release/hunk of functionality until sometime in the future. Additionally, you can stash your current task deliverables, go do something else, and come back to them later.
- Bisecting allows you to do a binary search through releases of code to identify the release that caused a bug. Kick ass.
Metaprogramming in Groovy by Brian Sam-Bodden was the third session I attended. BSB did a good job of going over the major metaprogramming techniques in Groovy. Additionally he had enough examples of Groovy code with TextMate that forced my hand to download it and see if it will cure what ails me with IntelliJ in dealing with Rails and Grails. Stream of conscience notes on metaprogramming with Groovy:
- Much simpler than using dynamic proxies in Java
- Similar to ruby it allows on the fly evaluation of code via evaluate
- Duck typing like ruby with respondsTo
- See yesterday's bits on methodMissing and invokeMethod
- obj."$methodToCall"() is valid Groovy code that will try to call the contents of methodToCall as a method on obj. In my opinion that code is utterly disgusting.
Also, the inevitable Ruby v Groovy topic came up as it did at lunch with me and a few others. There still seem to be zealots on both sides and I wish for the life of me they would just shut up.
My 2 cents are this. Use whatever makes most sense for your environment and team. At my consulting company, that is Ruby b/c I have a lot of .NET fellas that I would like to roll into and out of projects whether it is deployed on MRI, JVM, or DLR. The differences at my admittedly noob perspective are few and far between with the two languages. If it was a room full of Java developers, Groovy might make more sense because it is an easier transition for Java heads. I don't care what you choose for your environment, just quit bitching about the other side.
EJB3 Testing by Joseph Nusairat was my final session of the day. Joseph covered a wealth of testing frameworks in a very code centric presentation. The session was very interactive and covered some cool mocking techniques outside of the realm of EJB3, like dealing with mocking static methods. My attention span was slipping this late in the day, but here is a set of highlights:
- Easymock provides the typical set expectations, record and playback functionality. It is still probably the most proven, well documented, and easy to learn of the mock frameworks.
- JMockIt is a relatively new player with some cool support for AOP and Hibernate. Please notice the IT at the end of the name. JMock is a different framework. Unlike EasyMock and JMock, JMockIt is a very small and straightforward API that can be used to test methods w/o dynamic proxies or cglib.
- EJB3Unit has some very cool facilities. It provides an in memory database out of the box (HSQLDB), uses CSV files for populating the data and provides mocks of almost everything that you would need in an EJB 3 bean. If you have to use EJB3, this framework seems like a valid contender.
- Embedded JBoss is the last one covered and it seems like a good fit for mocking out an entire container when necessary and using JBoss.
- Mocking for unit testing, other tools still necessary for integration and functional tests.
I'm tired. See you tomorrow.
Friday, July 25, 2008
NFJS - Day 1
PreConf Arrived at NFJS. 2 cents before the conference gets started. Having the conference in two places like Phoenix and Columbus on the same weekend is diluting the talent (and the costs have gone up). Phoenix wound up with a few of my favorite speakers on the planet: Neal Ford, Venkat Subramaniam, and Ted Neward. Please don't get me wrong, listening to Stu Halloway, Scott Davis, and Keith Donald among others still makes for an excellent conference. However, in previous years, having to choose between Justin Ghetland, Stu Halloway, Dave Thomas, or Ted Neward all in the same time slot was a nice problem to have. If NFJS is to keep it's mantra as a value driven conference with A+ speakers then it needs to keep it's shows to 1 city per weekend.
Scott Davis - Groovy the Blue/Red Pill
Scott Davis has a presentation style that is really conducive to learning new technologies. He speaks at a very measured pace with a number of pauses, yet still with a passion that gets users excited. His first two talks were Groovy, how it is similar to Java and then how it breaks the mold.
Groovy - The Blue Pill covered the language at a high level and how it is seamlessly integrated with Java. I spent a good portion of this talk weighing whether that is a good or bad thing. I as a 10 year Java veteran have developed a very Java centric mind and it continues to bite me in the arse. When anonymous inner classes become natural for you in a programming environment, you have issues. Ruby seems to allow me to make a clean break from this mold. Groovy is a step up, but not in the same sense. That being said, I think it's seamless integration with Java make it an easier sell to management types. Hopefully the JRuby guys can keep up. Stream of conscience thoughts on the talk:
- GStrings while oddly named are very elegant
- Mixing in Groovy based unit tests is a no brainer for ease of adoption and powerful mocking
- Triple quotes surrounding XML blocks makes you ignore quotes and newlines (Cool for XML)
- Groovy converts all checked exceptions to unchecked exceptions
- Powerful scripting: s.class.methods.each{println it}
Groovy - The Red Pill covered some of the more interesting pieces of meta-programming in Groovy. Here is where the obvious Ruby influence shows up in Groovy. The ExpandoMetaClass accommodates closures in a syntax that is less intuitive then blocks in Ruby to me. It's called ExpandoMetaClass though so bonus points there. The keyword delegate can be used to access the thing within EMC. Overloading operators is limited to a specific set and done in a manner that is less than intuitive (implement putAt(b,c) for a to get a[b]=c). Groovy also provides methodMissing and invokeMethod to get peeps closer to Ruby like syntax. My conclusion after this session was I'll use Ruby wherever I can, then Groovy, and finally Java.
Scott Davis did such a nice job presenting the first two Groovy talks, I stuck around for his Grails for Struts Losers talk. That wasn't the exact title, but I think I captured the gist of it. This was a gentle intro to Grails and managed to show it's benefits quite nicely over existing Java web frameworks (struts in this case). The framework is very clearly alot of the concepts of Rails that work well in a Java/Groovy centric environment. I spent the session trying to get Grails up and running in my environment and stumbled into an issue that clearly articulated Grails v Rails. I left parens off a method call and it blew up. WTF? Basically it was trying to find a property of that name instead of finding a method. Luckily, I had a Grails book co-author next to me to help troubleshoot. For those of you keeping track at home, Rails 1, Grails 0.
Scott Davis - Groovy the Blue/Red Pill
Scott Davis has a presentation style that is really conducive to learning new technologies. He speaks at a very measured pace with a number of pauses, yet still with a passion that gets users excited. His first two talks were Groovy, how it is similar to Java and then how it breaks the mold.
Groovy - The Blue Pill covered the language at a high level and how it is seamlessly integrated with Java. I spent a good portion of this talk weighing whether that is a good or bad thing. I as a 10 year Java veteran have developed a very Java centric mind and it continues to bite me in the arse. When anonymous inner classes become natural for you in a programming environment, you have issues. Ruby seems to allow me to make a clean break from this mold. Groovy is a step up, but not in the same sense. That being said, I think it's seamless integration with Java make it an easier sell to management types. Hopefully the JRuby guys can keep up. Stream of conscience thoughts on the talk:
- GStrings while oddly named are very elegant
- Mixing in Groovy based unit tests is a no brainer for ease of adoption and powerful mocking
- Triple quotes surrounding XML blocks makes you ignore quotes and newlines (Cool for XML)
- Groovy converts all checked exceptions to unchecked exceptions
- Powerful scripting: s.class.methods.each{println it}
Groovy - The Red Pill covered some of the more interesting pieces of meta-programming in Groovy. Here is where the obvious Ruby influence shows up in Groovy. The ExpandoMetaClass accommodates closures in a syntax that is less intuitive then blocks in Ruby to me. It's called ExpandoMetaClass though so bonus points there. The keyword delegate can be used to access the thing within EMC. Overloading operators is limited to a specific set and done in a manner that is less than intuitive (implement putAt(b,c) for a to get a[b]=c). Groovy also provides methodMissing and invokeMethod to get peeps closer to Ruby like syntax. My conclusion after this session was I'll use Ruby wherever I can, then Groovy, and finally Java.
Scott Davis did such a nice job presenting the first two Groovy talks, I stuck around for his Grails for Struts Losers talk. That wasn't the exact title, but I think I captured the gist of it. This was a gentle intro to Grails and managed to show it's benefits quite nicely over existing Java web frameworks (struts in this case). The framework is very clearly alot of the concepts of Rails that work well in a Java/Groovy centric environment. I spent the session trying to get Grails up and running in my environment and stumbled into an issue that clearly articulated Grails v Rails. I left parens off a method call and it blew up. WTF? Basically it was trying to find a property of that name instead of finding a method. Luckily, I had a Grails book co-author next to me to help troubleshoot. For those of you keeping track at home, Rails 1, Grails 0.
Monday, July 21, 2008
Tech Ridden Month
I have 3 different blog posts in the making right now and I unfortunately don't see myself having enough time to complete them in the next month. A wide variety of activities are chewing up almost all of my free time, but most of it is tech related. Here's a look at my schedule:
7/22 - Speaking about Spring at the Cincinnati Java User's Group
7/25 - 7/27 - Attending NoFluffJustStuff in Columbus
7/31 - 8/4 - Vacationing with wife in Cabo San Lucas (WOOHOO!)
8/15 - 8/17 - Attending eRubycon in Columbus
I'm extremely excited about all of these opportunities but it will nonetheless continue my procrastination of blogging. Please sit tight and check back in mid August for more content on Spring, Ruby, IntelliJ, and IT Leadership.
7/22 - Speaking about Spring at the Cincinnati Java User's Group
7/25 - 7/27 - Attending NoFluffJustStuff in Columbus
7/31 - 8/4 - Vacationing with wife in Cabo San Lucas (WOOHOO!)
8/15 - 8/17 - Attending eRubycon in Columbus
I'm extremely excited about all of these opportunities but it will nonetheless continue my procrastination of blogging. Please sit tight and check back in mid August for more content on Spring, Ruby, IntelliJ, and IT Leadership.
Tuesday, June 10, 2008
Ruby Integration with Spring
I recently gave a presentation at COJUG on ten facilities in Spring that you may not know much about. I saved my favorite for the last. Dynamic Language integration. This facility has been around since Spring's 2.0 release, but has been mired in the relative obscurity of Chapter 24 of their docs.
While many IT managers might be hesitant to adopt a language like Groovy or Ruby for their production environment due to misconceptions about performance, security, or what have you. The management types should have very little concern with testing code making extensive use of dynamic languages. If Ruby or Groovy provides a lower barrier of entry for complex testing or mocking, why not make use of it?
Spring provides the typical DI goodness of abstracting away the underlying implementation and allowing the developer to switch from mock to production code without changing client code. In the case of Ruby backed implementations, JRuby provides the hooks to allow the .rb file to be recognized as an implementation of the Java interface.
Here's a simple interface implemented in Java with which I've created a Java and a JRuby implementation.
A JRuby based implementation of this only has a few tricks like including the library and calling a method to include the class
Finally, with the spring integration facilities, a few lines of xml locates the file and plumbs in the implementation. Client code accesses the Java interface, none the wiser to the Ruby implementation.
There are a couple of gotchas to keep in mind with JRuby/Groovy Spring integration:
- JRuby 1.1 is not supported until Spring Framework 3.0, use JRuby 1.0
- Model code after what I have above, not what is in the Spring reference docs. At last check the docs were somewhat confusing in the use of include versus include_class
- AOP can be used to wrap the dynamic beans just as if they were POJOs. The one big caveat here is to make sure they are implementing an interface. Class based proxies will not work
Spring's support for dynamic language beans is pretty powerful in it's simplicity. The uses of this technology are much farther reaching than just mock scenarios, though. JRuby or Groovy files can be polled and reloaded without compilation or server restarts. This can be immensely useful for dynamic portions of applications like lightweight rules, environment configuration, validation, or even web site navigation.
Hope this helps get you started with integrating dynamic languages into your Java code. Please leave a comment with your scenario if you are using or planning on using dynamic languages integrated with Spring.
While many IT managers might be hesitant to adopt a language like Groovy or Ruby for their production environment due to misconceptions about performance, security, or what have you. The management types should have very little concern with testing code making extensive use of dynamic languages. If Ruby or Groovy provides a lower barrier of entry for complex testing or mocking, why not make use of it?
Spring provides the typical DI goodness of abstracting away the underlying implementation and allowing the developer to switch from mock to production code without changing client code. In the case of Ruby backed implementations, JRuby provides the hooks to allow the .rb file to be recognized as an implementation of the Java interface.
Here's a simple interface implemented in Java with which I've created a Java and a JRuby implementation.
A JRuby based implementation of this only has a few tricks like including the library and calling a method to include the class
Finally, with the spring integration facilities, a few lines of xml locates the file and plumbs in the implementation. Client code accesses the Java interface, none the wiser to the Ruby implementation.
There are a couple of gotchas to keep in mind with JRuby/Groovy Spring integration:
- JRuby 1.1 is not supported until Spring Framework 3.0, use JRuby 1.0
- Model code after what I have above, not what is in the Spring reference docs. At last check the docs were somewhat confusing in the use of include versus include_class
- AOP can be used to wrap the dynamic beans just as if they were POJOs. The one big caveat here is to make sure they are implementing an interface. Class based proxies will not work
Spring's support for dynamic language beans is pretty powerful in it's simplicity. The uses of this technology are much farther reaching than just mock scenarios, though. JRuby or Groovy files can be polled and reloaded without compilation or server restarts. This can be immensely useful for dynamic portions of applications like lightweight rules, environment configuration, validation, or even web site navigation.
Hope this helps get you started with integrating dynamic languages into your Java code. Please leave a comment with your scenario if you are using or planning on using dynamic languages integrated with Spring.
Monday, June 9, 2008
Software Development Meme
Mark Blankenship posted his own personal history of software development and charged a few of us with posting the same. Here's my background:
How old were you when you started programming?
I remember my first official "programming" class was my sophomore year in high school so roughly age 15. I was officially playing around with a Commodore 64 as early as age 8 though. While that was mostly gaming, the memory and file models puzzled and intrigued me back then. My cousin and I would waste hours playing Mission Impossible on the C64 though. That tended to get in the way of any real programming back in the day, establishing a pattern of gaming over real work that plagues me still.
How did you get started in programming?
My brother is 5 years older and he was already starting to see some serious need for programmers while he was off at college. I was but a young lad in high school, focused more intently on sports, girls, and parties at the time. When I took my first real course at his advice though, I was hooked. So, brotherly encouragement coupled with a strong background in math. My father is a science teacher as well so he was always giving me a slight kick in the rear to pursue any and all topics that stoked my interest.
What was your first language?
BASIC, baby! I remember sitting next to a guy in that first course who nearly had the mental capacity to bend spoons and levitate people. He scored a 35 on his ACTs and a 1520 on his SATs, no joke. He was scary smart. I believe he later became a nuclear physicist, but I'm not totally sure. Anyway, he wrote a 5 level Zork type game in that class in the first two days we were there. That opened my eyes to the power of programming. Thanks Bill!
What was the first real program you wrote?
The first open canvas program I wrote was in a computer graphics class my junior year in high school. I built a dart board type game that allowed two people to compete to see who could get the dart closest to the center. By compete I mean that you merely alternated pressing a button to throw darts and they went to random spots on the board but it was still pretty cool.
What languages have you used since you started programming?
Probably missing some but here goes:
BASIC
Pascal
Modula-2
C
C++
Java
Smalltalk
Lisp
Fortran
SQL
HTML/Javascript
Ruby
C#
ASP.NET
What was your first professional programming gig?
I hired on as a paid intern thanks again to my bro. I was told I would be working on a C/C++/SQL based project for a retail services company. Instead I was working on an S1032 database with Fortran code literally printing off reams of green bar code snippets. If that place didn't have a ping pong table on site that rolled out every day at 5pm I would've probably gone postal. That assignment nearly made me into a history major.
If you knew then what you know now, would you have started programming?
No question about it. If anything I would've been more driven to succeed in this profession and spent more of my free time learning and pushing my limits. I was largely a slacker through high school and college and it set me behind starting out in the real work force. While it did enable me to thoroughly dominate OSU's entire campus in NHL 93 on the sega genesis, it also nearly caused me to drop out, become disowned, and live life in a van down by the river. I was lucky to find my niche once again but I wonder what I would've accomplished if I would've truly applied myself.
If there is one thing you learned along the way that you would tell new developers, what would it be?
Get comfortable with change and figure out the best way for you to learn. Change comes at you at all times from all directions in this field. Requirements are never set in stone, business direction can sometimes sway with the wind, and technology will certainly never be static. While Java has been around for 14 years now, the language it is today is worlds apart from what Gosling and co pushed out to us in the form of crApplets in 1994. All of the people in this field that I want to surround myself are quick learners and very adaptive. If you can roll with the punches figure out things quickly, then you'll never cease being marketable.
What's the most fun you've ever had ... programming?
I'm not sure I've ever had a moment of euphoria while writing a piece of code, but there was one time when I solved a huge showstopper of a bug that was visible at every level of our company. We had been seeing our application lock up the server completely on a random basis for about 2 weeks. After code inspection day 10 I finally stumbled upon an infinite recursive subroutine that was nested 142 levels deep in app server that was impossible to debug. Finally getting it resolved wasn't fun as much as it was like someone moving a car that had been parked on your foot.
That being said, I think I've had fun at every programming job I've ever been in. I attribute that solely to the various people that I've worked with, though. I have yet to work at a client yet where I've woken up with an utter feeling of dread. Maybe I'm just lucky, but I can rattle off a number of people from every client I've been at who I could call right now to go grab a beer. I think the problem solving is always fun and gratifying but working with people you genuinely want to be around is priceless.
Next up:
I'm throwing the guantlet down for another group of peeps to answer these questions:
Matt Marquand
Kevin Munc
Steve Harman
Jon Kruger
Steve Horn
How old were you when you started programming?
I remember my first official "programming" class was my sophomore year in high school so roughly age 15. I was officially playing around with a Commodore 64 as early as age 8 though. While that was mostly gaming, the memory and file models puzzled and intrigued me back then. My cousin and I would waste hours playing Mission Impossible on the C64 though. That tended to get in the way of any real programming back in the day, establishing a pattern of gaming over real work that plagues me still.
How did you get started in programming?
My brother is 5 years older and he was already starting to see some serious need for programmers while he was off at college. I was but a young lad in high school, focused more intently on sports, girls, and parties at the time. When I took my first real course at his advice though, I was hooked. So, brotherly encouragement coupled with a strong background in math. My father is a science teacher as well so he was always giving me a slight kick in the rear to pursue any and all topics that stoked my interest.
What was your first language?
BASIC, baby! I remember sitting next to a guy in that first course who nearly had the mental capacity to bend spoons and levitate people. He scored a 35 on his ACTs and a 1520 on his SATs, no joke. He was scary smart. I believe he later became a nuclear physicist, but I'm not totally sure. Anyway, he wrote a 5 level Zork type game in that class in the first two days we were there. That opened my eyes to the power of programming. Thanks Bill!
What was the first real program you wrote?
The first open canvas program I wrote was in a computer graphics class my junior year in high school. I built a dart board type game that allowed two people to compete to see who could get the dart closest to the center. By compete I mean that you merely alternated pressing a button to throw darts and they went to random spots on the board but it was still pretty cool.
What languages have you used since you started programming?
Probably missing some but here goes:
BASIC
Pascal
Modula-2
C
C++
Java
Smalltalk
Lisp
Fortran
SQL
HTML/Javascript
Ruby
C#
ASP.NET
What was your first professional programming gig?
I hired on as a paid intern thanks again to my bro. I was told I would be working on a C/C++/SQL based project for a retail services company. Instead I was working on an S1032 database with Fortran code literally printing off reams of green bar code snippets. If that place didn't have a ping pong table on site that rolled out every day at 5pm I would've probably gone postal. That assignment nearly made me into a history major.
If you knew then what you know now, would you have started programming?
No question about it. If anything I would've been more driven to succeed in this profession and spent more of my free time learning and pushing my limits. I was largely a slacker through high school and college and it set me behind starting out in the real work force. While it did enable me to thoroughly dominate OSU's entire campus in NHL 93 on the sega genesis, it also nearly caused me to drop out, become disowned, and live life in a van down by the river. I was lucky to find my niche once again but I wonder what I would've accomplished if I would've truly applied myself.
If there is one thing you learned along the way that you would tell new developers, what would it be?
Get comfortable with change and figure out the best way for you to learn. Change comes at you at all times from all directions in this field. Requirements are never set in stone, business direction can sometimes sway with the wind, and technology will certainly never be static. While Java has been around for 14 years now, the language it is today is worlds apart from what Gosling and co pushed out to us in the form of crApplets in 1994. All of the people in this field that I want to surround myself are quick learners and very adaptive. If you can roll with the punches figure out things quickly, then you'll never cease being marketable.
What's the most fun you've ever had ... programming?
I'm not sure I've ever had a moment of euphoria while writing a piece of code, but there was one time when I solved a huge showstopper of a bug that was visible at every level of our company. We had been seeing our application lock up the server completely on a random basis for about 2 weeks. After code inspection day 10 I finally stumbled upon an infinite recursive subroutine that was nested 142 levels deep in app server that was impossible to debug. Finally getting it resolved wasn't fun as much as it was like someone moving a car that had been parked on your foot.
That being said, I think I've had fun at every programming job I've ever been in. I attribute that solely to the various people that I've worked with, though. I have yet to work at a client yet where I've woken up with an utter feeling of dread. Maybe I'm just lucky, but I can rattle off a number of people from every client I've been at who I could call right now to go grab a beer. I think the problem solving is always fun and gratifying but working with people you genuinely want to be around is priceless.
Next up:
I'm throwing the guantlet down for another group of peeps to answer these questions:
Matt Marquand
Kevin Munc
Steve Harman
Jon Kruger
Steve Horn
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