More 2007 Predictions

My significant other just told me that I just made prediction only for Java and Ruby. That with the 2007 Predictions title, I shouldn't have such a narrow field of predictions. So here are more predictions :-)

Strong weather all over the world

2006 was relatively calm weather wise. With the global warming having more and more impact on our environment, I predict that 2007 will break every record in extraordinary weather related events.

War in many parts of the world

War is going (continue) to rage in many parts of the world. Too many innocent will continue to die due to selfish leaders ambitions.

Civil liberties will continue to be challenged

Civil liberties in most developed countries will continue to be challenged. Mostly in the name of so-called security or war against terror. The fact is that all these actions against civil liberty reduce security and put more oil on the war against terror fire.

Love will still be in the air

Even if bad things happen to the world and it's population, love will still be a great driver in human beings. Even in horrible times (which I don't believe we are in) love always find it's way!

So this is it! More predictions!

Luv U Annie :-D

2007 Predictions

Everybody doing it! Not wanting to be left in the cold, I will follow the herd and make predictions for 2007.

RoR will run flawlessly on a Java Application Server

The good people from JRuby are making incredible progress since they've been hired by Sun. We will soon be able to run RoR applications with no (or very little and trivial) modifications on Glassfish or other Web Container. Will that makes RoR application more scalable? I'm not sure. But it will increase RoR momentum in Java shops. When you talk about RoR to a java shop, the first question they have is "Will it run on Tomcat|WebLogic|WhebSphere|...?"

JRuby will take the top spot for scripting the Java platform

To the demise of Groovy, JRuby will take the spotlight. The main reason is the previous prediction. Once you can run RoR on a Java application server, nobody will need Grails. Grails is the only use of Groovy that create adoption.... Unless some other killer Groovy application, tool or framework is created.

RoR adoption continue

That's a fairly conservative prediction. RoR as a lot of momentum.

Java 6 adoption will start slowly in Q3

While Java 6 is out. It's adoption will grow slowly and will mainly be driven the scripting language support. Java 5 had many compelling reason to get adopted by many shops, but many many many application are still running on Java 1.4. Beside scripting support, there is nothing compelling enough in Java 6 to make it's adoption within the enterprise faster that Java 5.

Something will happen in Java build tool space

A lot of people are tired of Ant . Maven is cool, but lacks flexibility. Scripting language is getting more attention... We have Gant, Raven, JRake and many other existing or yet to be created build tool that use scripting language. By the end of the year, one of them will start getting a lot of traction. My best guess for now is Raven.

Java Specification Requests will become less and less relevant

The JCP is not working very well. It's too lengthy. Design by comity does not work well. Many JSR do not stand the sand of time. Today JSR mostly reflect some existing API with less feature (JPA vs Hibernate for example). They do not offer innovation, they just tend to seal mature innovative technology in the platform. New language features takes too long to traverse the JCP and with the open sourcing of Java, it will become easier for one group to add new feature to the language and to make a Java distribution of it's own. And with JSR like JSR-277 that create more turmoil than solve any problem, more and more people loose interest and faith in the process. Sun is not even interested in really supporting existing JSRs. We have a JSR for Groovy, but Sun hire the JRuby developers without giving any resource to Groovy. That's it! I made my prediction for 2007. This is probably my last post of the year, I will try to post a bit more often next year! In the mean time, have a Great Christmas and a really Happy New Year!


DB2 JDBC Driver hate my Date!

It's been a long time since I worked on a project that uses DB2 for the database. I always preferred DB2 to Oracle because it consume less resources (and it's much easier to install) on a developer machine.

But today I hit a strange issue...

I need to create a query that has a condition on a DATE column in some database. So my Java method that needs to do the query, I receive a java.util.Date argument. This method uses Spring-Framework Hibernate templates to do the query. Basically my query looks like this :

getHibernateTemplate().find("from Stuff s where s.effectiveDate <= ?", today)

I run a unit test that uses HSQLDB and every thing is fine.

But when I ran the same query in the application running on top of DB2, I got a nice SQLException from the DB2 JDBC Driver. The cause of the exception is :

com.ibm.db2.jcc.a.SqlException: DB2 SQL error: SQLCODE: -301, SQLSTATE: 07006, SQLERRMC: 3

The specified SQLSTATE says that this has something to do with data conversion. Huh! I have a DATE column and I pass a Date object! That should be fine (actually it is fine with MySQL, Oracle, HSQLDB and probably many other).

After a googling a bit, I found out that DB2 (the JDBC Driver) expect to receive either a java.sql.Date or a java.sql.Timestamp (depending on the type of the column). So in my case, I had to pass a java.sql.Date.

The fix is simple, I just have to create a java.sql.Date when doing the request :

getHibernateTemplate().find("from Stuff s where s.effectiveDate <= ?", new java.sql.Date(today.getTime()))

In my opinion, this is insane! It is the JDBC driver job to convert the passed data-type to something the database can handle.


added: Emmanuel's Development References search engine

I've just created a new search engine using Google Coop. You can start using it on by entering search terms on the search box on the right.

You may also add it to your browser's (Firefox 2.0 or IE 7) search engines.

This search engine is customized to search Java, Ruby, Rails, Hibernate and Spring Framework API and reference documentation. More API and reference documentation for things that are in my area of interest will be added in the future.


JSR-277: At last... a module system for Java!

The early draft for JSR-277 has been made available. This is good news! We will have a module system for Java. Its a bit late in the game... Ruby has a module system (GEM), Perl has CPAN, Linux has many... Why did it take so long to have one for Java? Maybe it did not itch that many people. But then why would the Maven team choose to create a repository for dependencies management, it must have itch!

I did a quick read of the specification... And here are my first reaction :
  1. Great! A module system for Java... At last, Java application will be easier to install and we will have a dependable versioning system,
  2. Why do I need to specify in the module definition all the classes that are present in the module? Maybe I did not understand the value of the "members" definition, but I guess that everything inside a module should be a module member. I see no reason to duplicate that information,
  3. I could say the same thin about the "class-exports". Why does the module system need this? It could use class visibility modifiers to do the same thing. I can see a bit of value if it was there to suggest the main entry points and/or API of the module. It should be optional,
  4. There is no use cases on how to install and manage existing module using tools. The specification says that it does not specify any tools. I believe that local repository management tools are a must and should be provided and made standard. At least a command-line tool should be specified. Just like we have a standard specification for using the "java" command even if it has implementation specific options.
Overall, I think this is great news. It does come a bit late and will not be available unto Java 7. But this will still be a great improvement over the current situation.


Ant without the XML

Yet Another Build Framework was announced today on The Server Side. Gosling is much like Ant (according to the website, it's a fork of Ant) but without the XML. For a start, this is good news. Instead of using XML, you use Java to code your build script.

Do we really need another build framework? Sure writing build script in XML is not very convenient and has its limitations. But we have Maven2. Maven2 is still XML, but it is not build script that you write in XML, it's just your project configuration. Maven2 is the perfect implementation of DRY for your build script. After more than 10 years of Java existence, why would one still have to write in is build script the steps required to produce a JAR file?

Does this mean that Gosling has no future? No! I think it's very nice to have an alternative to Ant to create build script (for those who don't like Maven2 very much). I also think that this would be a nice framework to create build task for Maven2. Because you are using code to create your build script, you can use a debugger to debug them. In that respect, it's much better than Ant and Maven2. I imagine, it would also possible to write libraries of tasks that could be downloaded on the fly (using dependency management) to be able to actually not repeat yourself.

Right now, this framework requires Java6. This is not a very good idea to drive adoption, Java5 and even Java 1.5 should be supported.

But the feature I would want the most for this project would be to be able to write my build script in a scripting language. Be it Ruby (with the help of JRuby) and/or Groovy! That would be much better than XML :-)


re Otaku, Cedric's weblog: FireFox 2: Please fix this before it's too late

In a recent post Cedric complains about changes in the behaviour and layout of Firefox tabs. I find this a bit amusing... First the behaviour and layout is not that different from the past. And I don't really think its worth a post outside of the developer mailing list. For my part, I like the way the close button is now positionned as in my Firefox 1.5 configuration (using the Tab Mix Plus plugin), my tabs close button is already there.

But what I found amusing is the irony...

Cedrics works for Google... And recently, Google made a complete redesign of  Google Reader. Without any warnings and by changing a lot of stuff (and making several usability mistakes). I guess that Cedric is not working for the Google Reader team. We just have to follow The new user interface thread on Google Groups to see, that this was a much bigger usability blunder than the Firefox 2 one.

The good thing about these two blunders... is that for Google Reader, you can revert back to the old interface if you want to (at least for now) and you can change some Firefox 2 settings to get the old behaviour!


The simplest thing to do...

I have been living in the Java world for a long time now. In this world full of patterns, complicated API and well intentionend flexible frameworks, we do not always follow the simplest path to a solution.

I'm currently working on adding some functionnality to an application that we wrote for a client last year. This application written in Java using JSF/Facelets/Spring/Hibernate and running on Tomcat.

For the new functionnality, I wish to move information from page to page but I don't want them to stay in the session for long. I also don't want to explicitely have to remove explicitely these object from the session. Now I could use request scope attributes to do that, but then if I choose to do a redirect instead of a forward, I will loose the information. I could also go with a more complicated option of using Spring WebFlow (or something similar). But I don't want to another layer and more configuration files.

In the weeks before starting this new project, I wrote some application using Ruby on Rails. The philosophy behind this framework is very different than the philosophy behind most Java frameworks. Here the DRY (Don't Repeat Yourself) principle is king. This contrast a lot with the stack I'm using as I have to define information about my controller, pages, beans in multiple places.

One of the concept I found useful in Rails is the Flash. The Flash is a hash structure like the session but it retains objects up to the end of the next request. It's a bit like the request scope with the added benefit of surving redirects.

So I thought, why not implement this in Java. For my Java implementation, I choose not to implement the "now" operation that is present in Rails as I did not really needed it. I also use a filter to do the management of the Flash.

This simple solution allow me to pass objects from page to page without having to polute the session to much. It has the benefit of allowing request-like scope to survive redirects. The current implementation may not work well with Ajax requests (I use Ajax4JSF and I have yet to find a way to differenciate Ajax request from normal requests, so the objects will be purge when doing an Ajax request unless I explicitely retain them when processing the Ajax request).

So here is the code (the two classes must be in the same package). Note that you can customize the Filter mapping to suits your particular needs.

import java.io.Serializable;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

public class Flash extends HashMap<String, Object> implements Serializable {
    private Map<String, Integer> time2live= new HashMap<String,    Integer>();
    public Object put(String key, Object value) {
        time2live.put (key, 1);
        return super.put(key, value);
    public Flash keep(String key) {
        if (containsKey(key)) {
            time2live.put(key, 1);
        return this;
    public Flash keep() {
        for (Map.Entry<String, Integer> entry : time2live.entrySet()) {
        return this;
    public Flash discard(String key) {
        if (containsKey(key)) {
            time2live.put(key, 0);
        return this;
    public Flash discard() {
        for (Map.Entry<String, Integer> entry : time2live.entrySet()) {
        return this;
    void manageFlash()  {
        for (Iterator<Map.Entry<String, Integer>> entries= time2live.entrySet().iterator(); entries.hasNext();) {
            Map.Entry<String, Integer> entry= entries.next();
            if (entry.getValue() == 0) {
                remove(entry.getKey ());
            } else {

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest ;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

 * @web.filter name="FlashFilter" display-name="Flash Filter"
 * @web.filter-mapping url-pattern="*.html"
public class FlashFilter implements Filter {
    public void destroy() {

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpRequest= (HttpServletRequest)request;
        Flash flash= (Flash) httpRequest.getSession(true).getAttribute("flash");
        if (flash == null) {
            flash= new Flash();
            httpRequest.getSession().setAttribute("flash", flash);
        chain.doFilter(request, response);

    public void init(FilterConfig filterConfig) throws ServletException {


Agility is about the customer...

See : Otaku, Cedric's weblog: Agile people still don't get it I have to agree with Cedric, when one focus on one specific agile process like TDD and then say he's doing Agile Software Development, then he's not being agile. Being agile is about giving customer more value for it's money. In the case of TDD, if you focus on writing test, then you do not focus on customer value. That does not mean that writing tests will not increase customer value, but there is a balance between the time you spend writing tests and the time you spend writing software for your customer that must be achieved (the famous 80-20 can be applied here). One of the Agile Principle is to deliver working software. Working software is software that the customer can use... Unit tests is not something the customer can use. Any agilist that focus on a particular methodology and/or process is not doing Agile Software Development. An agilist is someone who focuses on giving value to it's customer.

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