Lofi model @ work

2011-10-13T16:12:00.000-07:00

Why "Polyglot Programming" or "Do It Yourself Programming Languages" or "Language Oriented Programming" sucks?

Last year we saw the launch of a new Web programming language Dart - Structured Web Programming from Google. A very interesting approach to support web application development. Not so long after Go, Groovy, Ruby, Scala, << name your DSL here >>; we see Dart. Is it a good thing to have at least one programming language to solve one problem? The answer is, like we already know, it depends.

Some important backgrounds you should know about the multi programming language paradigm are following:

1. You can read Martin Fowler article about language oriented programming with language workbenches which enables you to write small programming languages easily. In this article I see everyone writing their small languages, everywhere. In this concept we see DSL (Domain Specific Language) as the future of our programming activities. Source: http://martinfowler.com/articles/languageWorkbench.html

2. Neal Ford talked about Polyglot Programming, combining multiple programming languages in application development. Later Mr. Fowler add this paradigm with Polyglot Persistence, using different type of databases within one application. Source: http://memeagora.blogspot.com/2006/12/polyglot-programming.html and http://martinfowler.com/bliki/PolyglotPersistence.html

Since 2006 I already discussed and collected some experiences in multi programming language paradigm:

1. I remember a “hot” discussion in year 2006 with Sebastian Meyen, chief in editor of JavaMagazin Germany, also the biggest organisator of Java Conference JAX. We agreed to see the future of programming in multi language paradigm concept. I also said that all those languages will be based on Java VM. I also told him that in one day SAP will move ABAP as a language which can be run within the Java VM, so just another language within the Java environment, no two different personalities any more. Today we see the beginning of this in the project called Caffeine ABAP. Source: https://cw.sdn.sap.com/cw/groups/caffeine

2. Also in year 2006 I had a project in which we also used different kind of languages and also creating our own DSL:

Java for the most implementation stuffs
UML for design of the business objects. We generate a lot of things using the concept of MDA (Model Driven Architecture)
Groovy for a lot of things, especially for writing unit tests
Based on ANTLR we create our own DSL for some aspects of the application

It was really exciting and we had some very good programmers in the project. The result was a very nice and flexible product, just as what we expected in the beginning of the project. Please read this article in German language for more information: http://www.sigs.de/publications/os/2009/02/dewanto_egger_OS_02_09.pdf

So after all those nice things about multi language paradigm I told you, why this sucks at the end? Here are some reasons from my point of view:

1. As typical in application development the problem comes first in the maintenance phase, after all the capable programmers leave the project. Did you, programming language creators ever try to teach a new programming language to a “normal”, 9 till 5 programmers? I’m not talking about 9 (am) till 9 (pm) programmers who love to learn every new languages. It is definitely tough to be proficient in one programming language. This is comparable with the languages we speak everyday. I’m not a native English speaker, so I’m quite sure that I made a lot of syntax and grammar errors in this article. It is possible to be able to speak three or four languages perfectly but this is an exception.

2. Did you ever try to maintain a big Struts web application with AJAX? Just try to add a functionality and you will end up with creating and editing a lot of files: Action and Form files, Struts XML configuration files, JavaScript files with JSON and also HTML or JSP files. Can you imagine to add Groovy, Scala, Dart additionally into that web app? The complexity of such a project is very high.

3. Creating a new programming language means that you also have to build the environment for it. Good IDE, good documentation, good community support, clear roadmap, backward compatibility are some points to be done. Groovy is a bad example of this. In the early version of this language the editor for Eclipse was really bad. After a while they improved the editor but they make a lot of basic changes in the language so your old groovy applications do not work anymore. You are punished to update to the new version. This never happens to Java. You still can compile Java 1.1 applications with Java 6 compiler.

4. Before you are creating your own DSL with e.g. ANTLR ask those language Gurus first, how hard it is to maintain a programming language for a long term. Before you discuss with them don’t ever create your own DSL. Especially if you are working for SME (Small and Medium sized Enterprise). With a small team and small budget you will never ever maintain your own language decently.

So in year 2012, six years after my support to Polyglot Programming, I hope to see following things happen:

1. One language for all aspects in one application is the best concept ever. I name this as “One for All Programming Language paradigm”. Just like we don’t use English for technical language, German as literate language and Indonesian as community language, to be able to communicate internationally with each other we just use English pragmatically for all aspects of our life. In Germany you need to speak German in all aspects to be able to communicate with others. My best solution sofar is Java + XML, that’s it, no more, no less. No mixing with Groovy, Dart, Ruby, Scala, << name your DSL here >> in one application. Especially if you are working as contractor, please don’t try to use all those languages just for a small Java web application. I don’t say that you should not use the other languages at all. The only thing which is important is not to mix those languages in one application. In SME you maybe also want to use just one programming language for all your applications.

2. Concept like GWT (Java to JavaScript compiler) or XMLC (XML compiler which compiles XML, HTML to Java classes) is great. You can work just in plain Java. Guice with all Java and no XML is also a great solution (I know that SpringFramework is also doing this with Annotations). Android is great because it uses Java as its application programming language.

As a conclusion I can only hope to see more such pure and plain Java solutions in year 2012!

2011-10-13T05:01:00.000-07:00

OpenID and OAuth: Step2 Protocol

My new article at heise.de about OpenID and OAuth: Step2 Protocol or also known as Hybrid Protocol OpenID and OAuth: OpenID and OAuth: Step2 Protocol.

Enjoy!

Lofi.

2011-06-16T23:07:00.000-07:00

Moving from Ant to Maven: Best Practices with Maven Plugins

I would like to share my experience of moving from "our reinventing wheel" of Ant build scripts to Maven standard.

I reworked some apps which have following characteristics:

(1) Java Version:

- The apps should be compiled with Java 6 version.

(2) Basic technologies:

- Some of the apps are using Model Driven Architecture/Model Driven Software Development things, it means we have some MDA/MDSD generators inside our Ant scripts, like AndroMDA or oAW.

- Almost all the apps use Hibernate, so we need to generate the whole Database scheme to be able to create the whole database automatically.

- Some of the apps use older version of ANTLR. So we have some of ANTLR source codes which have to be compiled.

- Some of the apps use older version of Groovy. So we have some of Groovy source codes which have to be compiled.

- A webapp uses GWT as presentation layer.

(3) Packaging:

- Some of the webapps have somekind of information about the version. For example the webapps have version.html file which should be automatically generated with some information like build timestamp, the person who build the app, the description of the app, etc.

- The apps or modules should be packaged as war or jar. Additionally they also include some additional information like installation documentation, SQL scripts, etc. which have to be package as a zip file separately.

- All of the apps or modules should also package the source codes additionally to the packaged artifacts, so we can debug the apps easily.

- The webapps need to package the class files additionally as a separate jar file, so that this can be added as a dependency into another Maven project or module.

(4) Test:

- The apps have some unit tests in JUnit.

- The apps have some integration test for SpringFramework context and database or service methods test in SpringFramework.

(5) Optimization:

- JavaScript, CSS of some webapps should be optimized using YUICompressor.

- JSP files should be precompiled with JSPC from Weblogic.

(6) Quality check:

- Quality check: the apps should be quality checked using Emma (code coverage) and CheckStyle (quality of the codes).

(7) Deployment:

- The webapps should be automatically deployed to Weblogic.

- All configurations should be automatically uploaded to the server.

- The database scheme should be automatically upgraded and downgraded.

(8) Development support:

- JRebel rebel.xml file should be automatically generated for chosen projects or modules.

Yes, our Ant scripts can do the (almost) whole things above. You can imagine how complex they are? Yes, everything are in the Ant scripts and you need to turn on/off the features you need. Remember how SAP works? Yes, we call this customizing! This is where I see the power of Maven. The plugin concept is just a better concept. Instead of having everything, we only have a small "core" and we add plugins on the top to fullfil our need. In case of the Ant scripts, you have everything (although you don't need all of them) and then you use switcher to turn them on and off.

So how did I solve the requirements above with Maven? Here they are, the plugins we need! In this article I just want to show you the plugins I used:

(1) Java Version:

This is quite simple, just add maven-compiler-plugin (2.3.2).

(2) Basic technologies:

- MDA/MDSD: In this case I have two main technologies: AndroMDA and oAW cartridges. For oAW 4.3.x cartridges we have fornax-oaw-m2-plugin (3.0.1). No problem at all. For AndroMDA 3.2 we also have some Maven plugins. My problem was that we use AndroMDA 3.1. In this version there are only some Maven 1.x available. So in this case I have to use maven-antrun-plugin (1.2). Using maven-antrun-plugin I can execute the AndroMDA task to generate the codes without any problems. I need to use the older version of this plugin because of the dependency to the older Ant version of the AndroMDA 3.1 task. One thing you should not forget: if you are generating codes you need to include the generated codes into your compile classpath. Using build-helper-maven-plugin (1.5) you can achieve this. Great!

- To be able to generate the SQL DDL scripts from Hibernate you just need to add hibernate3-maven-plugin (2.2). Working like a charm!

- Because we are using older version of ANTLR we also have to use maven-antrun-plugin (1.2) to be able to execute the ANTLR compiler.

- The same thing also happens with our older version of Groovy. Just use maven-antrun-plugin (1.2).

- For some GWT projects just use gwt-maven-plugin (2.2.0). This is a great Maven plugin (and the one and only) for GWT. This plugin has a very good documentation, so integrating it is quite easy.

(3) Packaging:

- The first step is to delete some of the target directories (generated directories). For this purpose we have maven-clean-plugin (2.4.1).

- To be able to generate a version.html file I use maven-resources-plugin (2.5). With this plugin you will be able to copy some resources (like version.html), parse the file and exchange all the variables with the content you like. In our case we need to exchange some variables with Maven pom.xml information (${maven.build.timestamp}, ${pom.version}, ${pom.description}, etc.). To be able to read these information you need to use at least the latest Maven 2.2.1. In the future we want to create our own Maven plugin to do this stuff, so that we can encapsulate the function better.

- To package additional information and files we have maven-assembly-plugin (2.1). This plugin is very flexible. So I can capture all the requirements of packaging additional zip files with it.

- To be able to deploy the source codes into Maven repository just use maven-source-plugin (2.1.2).

- In some of the webapps I need to package the "classes" into a separate jar file, so that this file can be added into a Maven dependency by other modules. In this case you can split the projects into two: one project for the "classes" and one project for the "webapp". But I did not want this because it will add the complexity of my projects (two projects instead of one). So I use maven-war-plugin (2.1.1) and add a configuration: attachClasses = true. That's it. You will get a new artifact for the classes with additional classifier: classes.

- In some business modules (Jar files) I need to exclude the model files which are the foundation of MDA/MDSD development style. For this purpose just use maven-jar-plugin (2.3.1) and exclude all the model files you don't want to be packaged in your Jar file. The cool thing is that your maven-source-plugin won't be disturbed by this action. So you will have all those model files still included in your source Jar file.

(4) Test:

- For unit test just use maven-surefire-plugin (2.8.1).

- For integration test just use maven-failsafe-plugin (2.8.1). It is important to separate unit and integration test because the integration test can take sometime. Using both plugins will make your project build more flexible, trust me!

(5) Optimization:

- For CSS, JavaScript optimization with YUICompressor just use yuicompressor-maven-plugin (1.1). It works without any problems. One thing you should aware of: if you are build a webapp you also need to configure maven-war-plugin so that it can copy the result of the optimization into the war file. This is also one thing you maybe want to use Maven profile concept, since you don't want to have optimized files within your development lifecycle.

- Precompiling JSP files with JSPC from Weblogic: this is still an open point. I can use maven-antrun-plugin, but I think that there should be a better way.

(6) Quality check:

- For Emma just use emma-maven-plugin (1.0-alpha-2).

- For CheckStyle just use maven-checkstyle-plugin (2.3). You also need to use surefire-report-maven-plugin (2.8.1) to be able to get a report on CheckStyle.

(7) Deployment:

- Automatic deployment war file with Weblogic can now be done easily with this plugin: weblogic-maven-plugin (10.3.4) from Oracle itself. This is great since this Maven support comes from Oracle. Here is the link to the Oracle documentation of this Maven plugin: Maven plugin from Oracle. To be able to define the server location without changing the pom.xml I use this plugin properties-maven-plugin (1.0-alpha-2). With this plugin you can read any properties file and you will have those properties accessible from your Maven build. Great stuff!

- If you want to be able to make automatic deployment you also need to support upload of configuration files to your server. For this purpose you can use this plugin: wagon-maven-plugin (1.0-beta-3). You can download and upload all kind of files with different kind of protocols (http, scp, ftp, etc.).

- The last important thing is to be able to automatically upgrade or downgrade your database scheme. This is an open point for me. There are some Maven plugins out there, but I had no time to analyse them. See my buzz for the list of them.

(8) Development support:

- To generate rebel.xml you can use jrebel-maven-plugin (1.0.7).

As a conclusion I just can say, Maven and its plugin ecosystem are great. No matter how complex your project you can still handle it easily with Maven plugins. My lessons learned is that DO NOT REINVENTING WHEEL! There are a lot of good Maven plugins out there! In case you cannot find one, just use maven-antrun-plugin. You can almost do everything with it. Just don't forget that you don't want that chaos back to Ant, so use it with precautions.

... and to all other developers who still doing their own build processes... try Maven, you won't regret!

Cheers,

Lofi.

2011-04-11T03:51:00.001-07:00

Inside-Out and Outside-In Integration of Webapps: Services and Extensions

In terms of integrating your webapp with other webapps and another way around I see two different integration types:

1. Inside-Out Integration

This is the standard way and almost every webapps available use this possibility. For other webapps to be able to use some functionalities of your webapp you often offer Web services (mostly in RESTful manner) which can be called from outside or other webapps easily.

In this area you offen need following strategies and standards:

Webservice protocol: REST for allowing to define the functionalities you want to export to other webapps.
OAuth (two and three legged) for allowing other webapps to calls your webapp services, authorization.
Sometimes OpenID for allowing other webapps to use the same login, authentification.

2. Outside-In Integration

This is still not commonly used in webapps development. In some desktop apps we know this as a concept of Extensions and/or Plugins (I use these terms exchangeable). This integration lets other webapps run in the context of your webapp.

Mostly this is the second step after you implement the first step above (Inside-Out integration) because you need all the things from the first step. All in all you'll need following strategies and standards:

Webservice protocol: REST for allowing to define the functionalities you want to export to other webapps.
OAuth (two and three legged) for allowing other webapps to calls your webapp services, authorization.
Sometimes OpenID for allowing other webapps to use the same login, authentification.

Additionally you also need following strategies and standards:

OpenSocial Gadgets to allowing other webapps integrating their Plugins or Extensions into your webapp. Users of your webapp will be able to install such Plugins or Extensions for their own needs.
AppStore or Market Place or WebStore (I use these terms exchangeable) to let your webapp users' easily browse, select, buy, install and review the Plugins or Extensions from a central repository.
Sometimes OSGi to let people extends your webapp with some new functionalities. This is however a tight integration of Plugins or Extensions with your webapp which is not easily done and needs more mature concept of your webapp (security, dependencies). Such an integration will not be available per user basis, instead it will be an extension per webapp. The system administrator of your webapp will likely install such Plugins or Extensions.

The main idea of doing these two integration concepts is to build a big ecosystem for your webapp so that a lot of people will use your webapp. By doing these two steps you will be able to open your webapp, not only that other webapps can integrate some functionalities or services of your webapp in theirs but also they will be able to extend the functionalites or services within the context of your webapp.

Let's take a short look of some successful webapps and how they support the two types of integration concepts I mentioned above:

1. Facebook: No doubt, both integrations have been done here. You have Facebook API (e.g.: Like Button) for the first and Facebook Apps (Canvas app) for the second.

2. Twitter: This webapp only supports the first integration as a collection of Twitter API (e.g.: Tweet Button, REST API). They still do not support the concept of Extensions for the second integration type.

3. Google Mail: This webapp supports both integration types. For the first type they offer e.g.: Email Settings API and OAuth Access to IMAP and SMTP API. For the second type you can use Sidebar Gadgets for visual Plugins and Contextual Gadgets for non-visual Plugins. For more information please take a look at this API documentation.

In my opinion, if you want your webapp to be successful, you need to think about both integration concepts directly in the beginning of your development. Don't create a webapp without a concept of ecosystem anymore!

Next time I'll take a look at how you can plan and implement both integration steps in a simple webapp project. What are the things you need to take care of.

Cheers,

Lofi.

2010-06-15T05:18:00.000-07:00

Wave Discussion: Ant vs. Maven

Let's discuss advantages and disadvantages using Ant and/or Maven!

2010-04-07T13:32:00.000-07:00

Don't leave home without these Eclipse 3.5.x (Galileo) Plugins...

M2Eclipse: http://m2eclipse.sonatype.org/sites/m2e
JarPlug: http://www.simontuffs.com/jar-plug
LogWatcher: Without Update Manager: http://graysky.sourceforge.net
OEPE (Oracle Enterprise Pack for Eclipse): http://download.oracle.com/otn_software/oepe/galileo
Google Plugins for GWT and GAE: http://dl.google.com/eclipse/plugin/3.5
Subeclipse SVN: http://subclipse.tigris.org/update_1.6.x
Android: http://dl-ssl.google.com/android/eclipse
ATF (Ajax Tools Framework): installation guide: http://wiki.eclipse.org/ATF/Installing

A good comprehensive list of Eclipse plugins can be found here: http://www.tutego.de/java/eclipse/plugin/eclipse-plugins.html

Have fun!

Lofi.

2010-03-11T12:55:00.000-08:00

GWT Spring Struts

This is a good starting point for integrating Spring, Struts and GWT:

http://www.jroller.com/masini/entry/template_project_for_gwt_with

Cheers,

Lofi.

2010-02-15T01:13:00.001-08:00

Top 10 Productivity Tools for Java Developers on Oracle Weblogic

A good presentation about the topic above: Top 10 Productivity Tools for Java Developers on Oracle Weblogic.

Enjoy!
Lofi.

2010-02-08T23:19:00.000-08:00

Custom Spring Component

HOW-TO write your own Spring Component: Custom Spring Component.

Enjoy!
Lofi.

2010-02-08T01:16:00.000-08:00

Spring DM Article in German Online JavaMagazin

Here is an online version of our article about Spring DM (OSGi). Following article (German language) about OSGi and JEE is also very interesting: JEE and OSGi.

Enjoy!
Lofi.

2009-11-20T04:59:00.000-08:00

HOW-TO: OEPE - FastSwap with Maven2 and M2Eclipse Plugin

At the moment there is not enough information if you want to jump start with OEPE (and of course using FastSwap) and Maven2 (using M2Eclipse plugin). This HOW-TO shows you how to achieve this. You need to have Eclipse (3.4 or 3.5), WLS (10.3 or 11) OEPE, Maven2 and M2Eclipse installed correctly before you can follow the steps below:

1. Create a web application with the webapp wizard (dynamic web project). Choose a webapp based on WLS (10.3 in my case). Please change following settings afterwards to be Maven complianced:

Source for web: src/main/webapp
Source for Java: src/main/java

2. Turn on Maven project on the project above ("mavenized the project") with M2Eclipse.

3. After you mavenized the project you can delete the directory build/classes since Maven uses target/classes directory. Everything should be customized to Maven directory structure automatically.

4. You can add

src/test/java - if you need it
src/test/resources - and also
src/main/resources

And don't forget to give a correct output direcory for each source directory (target/classes or target/test-classes). After that you will have following directory structure in your project:

5. Now you should be able to run maven "package" within your M2Eclipse plugin correctly. And also you should be able to deploy the web app in WLS just by doing "run on server".

6. You can skip this step because you are using OEPE which turned on FastSwap automatically. To make it sure that FastSwap works correctly, you can turn on FastSwap in the weblogic.xml file (please click on the image to make it larger).

Be careful: I get following problem if I turn on FastSwap in my weblogic.xml:

After turning on FastSwap in weblogic.xml file, the FastSwap mechanism does not work correctly! A change in a private field does not get updated in my webapp. If I turn this off again and redeploy my webapp, FastSwap is working correctly again. A change in a private field will be updated immediately. Do you get the same problem with your OEPE and WLS 10.3 here?

7. You have to add the "Maven Dependencies" container into your Java EE Module Dependencies for OEPE to be able to use all the jar files inside the Maven dependencies (please click on the image below to make it larger).

8. You made it. Now you can change your classes without having to redeploy the application and at the same time you still have all the advantages of using Maven2 in your project. Have fun!

Cheers,
Lofi.

2009-11-11T12:09:00.000-08:00

OAuth with Java

This is the third part of my article series about OpenID and OAuth in heise.de:

Article: Autorisierungsdienste mit OAuth

Enjoy reading!
Lofi.

2009-10-08T12:10:00.000-07:00

Spring Batch

Here are some good introductions to Spring Batch:

Have fun!
Lofi.

2009-09-22T12:37:00.000-07:00

XMind: A Cool MindMap Tool

I found this cool Open Source and Eclipse RCP-based MindMap tool XMind!

Enjoy,
Lofi.

2009-09-21T13:50:00.001-07:00

One Day in your Life... with UML2, oAW, Weblogic FastSwap, Oracle Enterprise Pack for Eclipse, Maven2 and SpringFramework...

In my new project - as usual in a software project - we have a very tight schedule. Using our old JEE application architecture (Oracle 10g, EJB 2.x, JFormular, Ant with Maven2 dependencies, full deployment EAR, WAR and EJB JAR on Weblogic 10.3 with Java6) would mean that we will have a long turn-around time (code, compile, deploy and test) for our development. Our build process with Ant does not support "naked" deployment", so it takes ages before the artefacts are built, jarred and can be deployed in Weblogic. In case that you only change one small thing in your web layer (JSP file, Java class) you will need to go through all those build steps. In combination that at that time I had an old development hardware (3 years old) you can imagine how horrible the situation was...

So I was searching for a better solution. We need a fast turn around time, especially in our web layer because I'm not an expert in JFormular and I definitely need to "try and error". At that moment I already know how easy to develop with GWT in hosted mode. You are just doing "ctrl-s" in Eclipse and make a reload on your browser. That's it, you will see all the changes directly. So your turn around process is just code, compile and test. No deployment anymore. You are very productive in this style. Amazing!

Luckily I found Oracle Enterprise Pack for Eclipse (OEPE) in combination with Weblogic FastSwap technology. With these stuffs you can do the GWT development style for JSP and any other web frameworks within your Eclipse as well. Not for all the things but it works very well. So after I found this I was thinking of making a new application architecture for our new project and here is the result:

1. Modeling strategies and technologies: UML2 (MagicDraw 16) with oAW generators. Actually I'm a fan of AndroMDA (yeah AndroMDA is a great Open Source project!), but because of certain circumstances we move to oAW (it was not my decision). From the application developer point of view I just need to generate the codes from the UML2 models. Nothing special here. In the mean time MagicDraw is becoming a very solid UML product. One thing which still needs some improvements is the file format (XMI) management. Since MagicDraw does not save the UML file in the native Eclipse UML file format you always need to export the file before it can get processed by oAW or AndroMDA. The export can take time if you have a big UML file.

I have to admit that my vision of "the next step in software development is reusing model components" is still not there. Four years after I wrote my MDA book I still don't see any movement that we are beginning to reuse models. But still it would be very cool if I need to have a user management component I can just import an UML2 user management module in my UML2 application module, afterwards I can customize the model und regenerate everything. At the end I can get a running application with a complete user management which is customized
for my application. Very cool but not a reality yet.

2. Implementation technologies: Oracle10g database, Weblogic 10.3, Hibernate 3.x.x, SpringFramework 2.x.x, JFormular (our own development for web framework):

I'm using OracleXE for development which is very good. Only for the integration test we use Oracle10g.

Weblogic 10.3 is a very solid software. There are some new things which I like in comparison with the older 8.1. Here are some points:

Support for FastSwap: This is great. In combination with OEPE (see below) you just make ctrl-s and reload on your browser and you will see the changes directly. Amazing, especially for development of web user interfaces. You also won't lose your session in the web application. So if you have an application in which you have to log in, you don't need to log in everytime you change something in your web application because your session is still there. There are some contrains in FastSwap but all in all you can life very good with FastSwap.
User interface of Weblogic 10.3 is a lot more better than the older version. Still you have a bug if you are using Chrome.
You can start Weblogic in a very slim version (without EJB, etc.), thanks to OSGi architecture of Weblogic. This is great if you just want to make a simple development with servlet.

3. Project structure and build process: Maven2. Actually I'm not fond of Maven2 because I always thought "I need my freedom and flexibility". I don't want to be dictated by a common structure and standard phases like in Maven. My project has always something specials so I need my own Ant task to get the flexiblity I need. I'm wrong, very wrong. After doing some stuffs in Maven2 I began to really like it. A very great build tool. I will never ever do my project without it again! Following points are the reason why I like Maven2:

The documentations of all those plugins are great. You can always find solutions to your problem in internet (I already forget how to do programming without internet ;-))
You have two great free Maven books which are very nice in case that you will need to understand something principally in Maven2 (Maven: The Definitive Guide and Better Builds with Maven). Something like Assembly or Profile for example.

And why is Maven2 should be your choice (instead of pure Ant)? Here are some reasons:

You can still use Ant in Maven2, so you actually don't lose your flexibility!
I already see some hand-written Ant tasks. OK you can surely standardized them all but almost all of them are just re-written of Maven goals (compile, test, package, install, deploy). So mostly they are quite useless. Especially in a small team of developers this is not applicable since one person needs to take care and always extend the build files. Did you ever try to extend Ant tasks which are not written by yourself? Have fun! Another thing is that in a lot of cases you will have to use the dependency management of Maven in Ant, so you are beginning using Ant task for Maven anyway. In this case just throw your Ant tasks away and start using Maven2. You can still integrate some of your Ant tasks directly in Maven2.

One thing I still don't like is the Maven2 Eclipse plugin. Yes this plugin is still buggy. After a long time of its existence it's a pitty that there is still no good Maven2 plugin for Eclipse. For more info - or problem - on Maven2 Eclipse plugin please continue reading.

Here is a list of topics which I found very useful during my first contact with Maven2:

Introductory article at JavaWorld: An Introduction to Maven 2
Maven2 with Weblogic 10.3: Integration
SpringFramework, Hibernate, Maven2, EasyMock, etc.: Gridshore: Open Source Software Development by Example

4. IDE: Eclipse 3.4.x with OEPE and Maven2 plugins: OEPE offers you a lot of good functionalities (starting, stopping server, some editors for Weblogic stuffs, etc.). One I really like is the FastSwap technology. At the moment some developers are using a remote installation of Weblogic 10.3. It's a pitty that FastSwap only supported for a local installation of Weblogic. I don't know if FastSwap is working for a remote installation with a Samba access. Maybe worth to try.

In conjunction with Maven2 Eclipse plugin there are some bugs still available. If you are seperating your presentation layer (web war) and your business layer (jar) in two different Eclipse projects you can't have the FastSwap technique in your business layer. You also cannot use the Maven2 plugin functionality "Resolve Dependencies within Eclipse IDE" which is actually pretty cool. So you always need to "install" the business jar file into your local Maven repository. Your web application needs to link this jar file directly. See this discussion for this type
of bug: M2Plugin and OEPE. I hope to see bug fixes for all these problems, so that we can use FastSwap also in our business layer like with SpringFramework, etc.

I also found that this Eclipse plugin is a good one (not a perfect one) to see changes of your Weblogic or your application log files: Log Watcher.

All in all, with all its bugs, OEPE and Weblogic FastSwap are great technologies and if you are using Weblogic you have to try these stuffs. You will never ever want to comeback to your old development process and steps. One thing to remember: Using FastSwap does not mean that you don't need to write unit tests anymore! FastSwap is a beautiful technology to quickly prototype applications and unit tests are there for you to be able to deliver high quality applications. So the combination of both is just what you need!

One thing I want to replace in our application is JFormular web framework. Maybe it was a good framework in the past but today I won't develop a new application with that framework anymore. GWT would be a better choice for web user interface.

Update:

I'm beginning to write some HOW-TOs and project examples for working with Eclipse, Maven2, M2Eclipse, OEPE, WLS 10.3 and FastSwap.
Here is a short introductory HOW-TO: OEPE - FastSwap with Maven2 and M2Eclipse Plugin.

Have fun and be productive!
Lofi.

2009-07-02T23:04:00.000-07:00

Bye bye SMTP - Welcome Wave Protocol

It's very interesting to see that Google has developed a new protocol for e-mail, yes SMTP is just too old and boring, Wave protocol will come soon - at least we already have one provider who will implement this new protocol, I call it as a "reference provider", yes, it's Google Wave :-)

Okay before I begin with this story, one thing we need to know:

"Wave is just a protocol (http://www.waveprotocol.org), a specification, just like SMTP, HTTP, HTML, TCP/IP, OpenID, OAuth, OpenSocial, etc. This means that everyone can implement this protocol to build some new products based on it".

"Google Wave (http://wave.google.com) is an implementation of the Wave protocol". A Google product which supports Wave protocol. I also call Google Wave as a reference implementation and reference provider of the Wave protocol.

If you want to understand the terminology in Wave protocol, please check out this article: Google Wave: A Complete Guide.

OK, with those information in the background we can start our discussion...

The big question for me is whether other e-mail providers like YAHOO!, GMX, Web.de, Lycos, etc. will also support this new Wave protocol. IMO this depends on the acceptance of the reference provider within the consumers. If Google Wave can attract a lot of people, all other e-mail providers will slow but surely become less important and their customers will leave them. Who cares to use that old e-mail, boring stuffs? The advantages of Wave protocol against SMTP are quite clear. And this is the point where they will also have to implement and add the new Wave protocol in their products.

What kind of impacts do we have from Wave protocol alltogether?

1. Technically we don't need to have client applications like e-mail SMTP client applications (Outlook, Thunderbird, etc.) since Wave is being designed for web applications. Maybe there will be some Wave client applications (WaveEagle at Mozilla?) but this is not a must. Yeah, Microsoft Outlook will have to do some diets ;-) Throw all those e-mail stuffs away. Just embed Internet Explorer.

2. We will see some new providers playing and fighting for market share. Yes, the "pie" will be open for everyone, come and join Wave protocol and develop your own Wave product. Yes, we can start from the beginning! Web.de, GMX, YAHOO! will still play a role but it can happen that...

Google Wave will get the most customers because their implementation is the first at the market. Marketing people know this as "first mover effect".
A newcomer "Swiss Inc." from Switzerland will get a lot of customers because their Wave protocol implementation is the most secure one. Yes, nobody can get access to their servers, also not their own goverment since they have their "Wave secret".
"WaveSign" (from V...Sign) offers you a real identity. It means that they will check you offline first, whether you are "the really" Lofi Dewanto before you can get a new Wave account. So everyone gets a Wave from this provider can be sure that the person really exists and the identity is checked.
It is possible to have "HotWave" (from M..., you know what I mean) rules the Wave world, because it is directly integrated within their operating system. All those Wavelets are directly integrated in the background screen and their widgets, not bad...

So, to all providers, let's get rumble...

3. How about spammer? Spammer will still find their way to "wave-spam". Please check out http://www.wavespam.net. You can get a wave account easily there, no identity check, nothing and of course you can use it to wave-spam everyone.

4. How are the business model(s) of those OpenWave providers? These won't change a lot. Just take a look those SMTP providers today. How can you earn money with consumer web applications today? Nothing. OK, I give up, ... advertisements, ads, and ads, ... :-)

I personally like the new Wave protocol and it's the time to throw away SMTP, so folks let's get started!

Just my 2 cents, happy Wavy!
Lofi.

BTW. here are some links on Wave protocol and Google Wave in German language:

2009-07-02T04:07:00.000-07:00

Transaction Management and Hibernate Sessions

This is a very good description of Hibernate Sessions from Atlassian: Transaction Management and Hibernate Sessions Guidelines.

Cheers,
Lofi.

2009-06-19T00:40:00.000-07:00

Bug in Chrome 2.0.x.x: Weblogic Console 10.3.x.x

If you are working with Oracle Weblogic console 10.3.x.x and you are using Chrome 2.0.x.x you won't be able to see the "advanced tabs" on the bottom of every pages of the console.

In some pages of the Weblogic console you can see at the bottom an "advanced tab" which can be opened by clicking on it. The tab will open smoothly in Firefox. Only in Chrome you won't see this tab, as if it were not existing at all. Just take a look at the two screenshots below (comparison between Firefox and Chrome 2.0.x.x for the same page).

Chrome 2.0.x.x - no "Advanced" tab:

Firefox 3 - with "Advanced" tab:

So be careful and use Firefox for Oracle Weblogic 10.3.x.x console...

Cheers!

2009-06-14T23:56:00.000-07:00

Nice Blogs about Java vs. RoR and GWT/GAE

Here are some interesting blogs:

Have fun!

2009-06-11T23:53:00.000-07:00

Use Case Points (UCP) Method

Here are some interesting articles about UCP method:

and... if you are a user of AndroMDA and MDA/MDSD in general don't forget to use the UCP cartridge from EJOSA.

Have fun!

2009-06-07T22:40:00.000-07:00

OpenID for Java (openid4java)

This is the second part of my article series about OpenID:

News: Identity Management: OpenID mit openid4java
Article: Tief in der Traumwelt

Enjoy reading!
Lofi.

2009-06-07T22:31:00.000-07:00

Google Wave and Open Wave Protocol

It's very interesting to see that Google tries to build a new email system: Open Wave Protocol. They could be successful since email protocol is just too old. Just take a look for example how people in Germany try to extend email to become secure: Bürgerportale. They try to stick to the old protocol and extend it with many extensions. Oh my dear...

2009-04-21T13:30:00.000-07:00

Internet Identity Management 2.0 (OpenID, OAuth and co.)

I began to write an article series in german language about Internet Identity Management 2.0. In this series I will cover OpenID, OAuth and co. Also - as usual - I will take a look at some Java libraries which are made to implement the specifications of those technologies.

This is the part one at heise.de Developer Channel:

Internet-Identität und Datenaustausch heute - Nutzung und Möglichkeiten von OpenID und OAuth

Enjoy reading!
Lofi.

2009-02-25T13:07:00.000-08:00

Product Line Software Engineering and Open Source Article in OBJEKTspektrum Magazine March/April 2009

At the end Frank and I managed to publish an article in OBJEKTspektrum magazine (March/April 2009) about PLSE in German language. In this article you can read the development of our software product line: ProMI...

Produktlinien-Softwaretechnik mit Open-Source-Produkten

"Mit der wachsenden Größe und Komplexität von IT-Systemen gewinnt die Wiederverwendung von Software immer mehr an Bedeutung. Hier versucht die Produktlinien-Softwaretechnik einen Beitrag zur Verbesserung der Wiederverwendung zu leiten. Anhand von praktischen Beispielen verdeutlicht dieser Artikel, wie Software-Produktlinien entstehen und mit Hilfe von Open-Source-Produkten einfach realisiert werden können. Zudem werden sieben "Best Practices" vorgestellt, die sinnvolle Unterstützung beim Einsatz der Produktlinien-Softwaretechnik geben."

Have fun!
Lofi.

2008-09-18T12:54:00.000-07:00

Dependency Management for Developers and Spring dm / SpringSource dm Server - An Introduction

I gave a short presentation about Google Guice and OSGi at Deutsche Post Com GmbH (in German language). You can download the PDF file of my presentation from the link below:

Dependency Management for Developers - An Introduction (PDF file)

The second part of my presentation (also in German language) about Spring dm for OSGi and SpringSource dm Server can be downloaded from the link below:

Spring dm for OSGi and SpringSource dm Server - An Introduction (PDF file)

I will also upload the whole examples in form of Eclipse workspaces, so stay tuned!

Have fun!
Lofi.

2007-06-11T13:59:00.000-07:00

Article: Pengukuhan Pustakawan Utama - Pustakawan Dituntut Lebih Profesional

There is an article about National Library Indonesia: Librarians in Indonesia should be more professional in their work. Check out this important article below:

Article about Pustakawan Utama.

Cheers,
Lofi.

2007-06-11T11:40:00.000-07:00

MDSD/MDA Frameworks: AndroMDA Cartridges vs. Sculptor

It's quite amazing to see the same things happen again and again... Reinventing the wheel seems is the way in computer science to make things better ;-)

To begin this blog with, which is a comment of the discussion in TSS about Sculptor: The idea of Sculptor is not new, also ArchitectureWare is not new... MDA/MDSD is not new as well...

Here are my opinions about Sculptor and AndoMDA and general about MDSD/MDA:

(1) I'm a very satisfied user of AndroMDA. AndroMDA is a very good framework for MDSD/MDA and is just comparable with ArchitectureWare. The latter is the framework in which Sculptor is written.

(2) Sculptor is comparable with AndroMDA Cartridges, which allow you to generate codes for its reference architecture. AndroMDA offers a lot of production-ready cartridges like:

Java (general purpose)
EJB, Spring, jBPM (business layer)
Struts, JSF (presentation layer)
...
And also for .NET!

All these cartridges are already available since more than 3 years! So they are quite mature.

Here is a very good description of the reference architecture in AndroMDA Cartridges for Java and here is for .NET reference architecture. And here are two articles about why using AndroMDA is the way to go.

(3) The difference between AndroMDA Cartridges and Sculptor is that AndroMDA Cartridges use UML as its DSL. Sculptor seems to invent its own text-based DSL. This would be a very interesting point to discuss. My questions here is: why using a new text-based DSL for implementing business applications? For this purpose UML is the way to go. Why? Because:

We have a lot of good UML tools.
A lot of people (also business people) understand UML (or a part of UML). If you are using a text-oriented DSL you will loose the capability to talk with the business people.
How is the quality of the editor for Sculptor DSL? I see a lot of good DSL but almost all of them have a poor editor support. See my blog about Groovy and unit testing.
In my experience with DSL using ANTLR it is not easy to design a clean DSL. It is very difficult to draw the line where you should stop putting more elements in your DSL. Typical problem: should I put String operations in my DSL? In the long term you will mimic the "lower" language.
Using UML and its extension mechanism (stereotype, tagged values, etc.) are mostly enough to handle all your requirements in business application development.

(4) The quality of the generated codes is the important part of choosing such a framework like AndroMDA Cartridges or Sculptor, since it will determine the quality of your application architecture:

How many developers have used and reviewed the cartridges and the generated codes?
How is the generality of the architecture? Will it fit for your needs?
Do I need to extend, change or rewrite the cartridges?

One thing for sure, you HAVE TO REUSE the cartridges to become productive. Changing or rewritting them make NO SENSE for a small team! I have experienced this again and again... Check out my older blog about this phenomenon. So you have to be able to add your requirements to the development of the cartridges and this means that the development team in the cartridge project should not consist a single developer!

In my experience I can say that AndroMDA has a very good support. A LOT of developers have tried and used their cartridges. The development of AndroMDA cartridges is a real Open Source development and those AndroMDA developers are very active!

Cheers,
Lofi.

2007-06-04T01:32:00.000-07:00

FTP Server in Java (and of course Open Source ;-))

Here are some interesting FTP servers written in Java and Open Source:

A list of available FTP servers (not only Open Source and Java) can be found in these sites:

It would be nice to have a complete comparison between all those available products because at the end you would only choose one product!

Cheers,
Lofi.

2007-05-24T00:02:00.000-07:00

The eclipse.ini File "Hell"...

If you want to change some settings in your Eclipse 3.2.x you have two choices:

Use the extra settings in your command line, something like eclipse -vm ... -vmargs ...
Put the extra settings into the eclipse.ini file, something like:
-vm
...
-vmargs
...

If you put your extra settings into the eclipse.ini file you have to be careful: Do not insert an empty line at the end of your eclipse.ini file. If you do this Eclipse will completely ignore your settings!

Cheers,
Lofi.

2007-05-02T01:30:00.000-07:00

Advantages and Disadvantages using Groovy for Unit Test (JUnit)

I'm collecting the advantages and disadvantages using Groovy for JUnit and found following interesting stuffs...

Advantages:

You don't need to implement inner classes which are very awful and bloat your test codes. Instead you can use closures. Using closures for writing your mock objects can make your test codes smaller and more compact!
File operations are very easy to implement thanks to AntBuilder. How many times do you need to make some file operations (delete, mkdir, ...) within your test codes? Doing this with java.io is not fun at all. Using AntBuilder for this purpose is a good thing, since Ant is predestinated to do this job. If you think that you could do the same thing in pure Java, you will find that this takes a lot more work. Using Ant directly in Java is unfortunately not straight forward. Example: to use the unzip Ant task you need to use the Expand Java class, which is not documented properly (so you need to dig into the Java source code). In AntBuilder you just use the same structure like your Ant file: unzip!
If you are using SpringFramework you can easily create the config files (application context) by using BeanBuilder. By using this concept you don't need to put separate XML files in your test project. Everything is integrated and centralized in your test class!
If you are using Ant for your build environment, you can integrate the compilation of Groovy classes easily since Groovy also offers an Ant task.

Disadvantages:

No source code formatter for Groovy: This is a real disadvantage for Groovy at the moment. If you are working in a team this could be a nightmare: reading the code with different formatting, CVS compare is difficult, ... are some examples to mention...
The Groovy plug-ins (code completion, syntax coloring, ...) - at least for Eclipse - is still very buggy.
You need to learn some new concepts like: closures - which is also an advantage after you understand them! Without closures you cannot implement inner classes in Groovy, which are mostly a must in writing unit tests.

The good thing about using Groovy for your unit tests is that you don't have to make the choice between Java and Groovy at one time! You can move slowly from Java to Groovy - of cource if you feel that you are more productive using Groovy to write your unit tests - as you wish and mix Java and Groovy unit tests in the same project!

A good place to start for Groovy and Testing is right here: Groovy Testing Guide.

If you have some points to add please let me know!

Cheers,
Lofi.

2007-03-18T01:58:00.000-07:00

A good Article about Indonesian Pharmacy System

Harapan Baru Dari Pergantian Kepala Badan POM

Hope to see something different after the head of POM replacement!

Happy reading,
Lofi.

2007-02-28T12:51:00.000-08:00

Bonner-Runde 26th. of February 2007 in Bonn

It was an interesting night in a round table presentation and discussion in Bonn, known as "Bonner Runde" which is managed by itemis GmbH. At this time, we - Wolfgang, Andreas and I - showed an introductory topic in AJAX:

AJAX - Grundlagen und Implementierungsansätze
"AJAX - Basics and Implementation Approaches"

We showed three different approaches of AJAX:

Using AJAX-enabled JSF components (ICEfaces) with Sun Java Studio Creator
Using hardcore JavaScript
Using XML11 - Cross Compilation from Java to JavaScript

At the same time we also explained classification criteria and characteristics for AJAX implementation approaches.

For more information please download the presentation files:
(1) AJAX - Grundlagen und Implementierungsansätze
http://lofidewanto.googlepages.com/AJAXinAction-BonnerRunde.pdf

(2) XML11 - AJAX without JavaScript
http://lofidewanto.googlepages.com/xml11-BonnerRunde-070226.pdf

Have fun!
Lofi

2007-02-10T05:02:00.000-08:00

MDA Book in German Language

My first book in German language about MDA (Model Driven Architecture) and VOFI (Visualization of Financial Implications) is now available:

Anwendungsentwicklung mit Model Driven Architecture
– dargestellt anhand vollständiger Finanzpläne

This book is my doctor dissertation from the year 2006 and is now published within the series of Advances in Information Systems and Management Science from Logos Verlag Berlin.

The good thing is that I will offer a free download for the PDF version - many thanks to Logos Verlag which makes this possible! So, if you can read German, you are welcome to download it ;-) For this purpose I'm searching some sponsors. As soon as I get some sponsors I'll put the PDF version somewhere in the internet. So, stay tuned!

If you want to buy it, just order from
Logos Verlag Berlin: ISBN 978-3-8325-1480-8

Or go directly to this order site:
Order MDA VOFI Book from Logos Verlag Berlin

Happy reading!
Lofi.

[updated 01.03.2007]
---

German

Anwendungsentwicklung mit Model Driven Architecture
– dargestellt anhand vollständiger Finanzpläne

Die modellgetriebene Anwendungsentwicklung, die von Object Management Group (OMG) als Model Driven Architecture (MDA) standardisiert wurde, nutzt Modelle als Hauptartefakte und zeichnet sich durch hohe Qualität und Produktivität gegenüber quellcodezentrierten Anwendungsentwicklungen aus.

Blasius Lofi Dewanto führt in der vorliegenden Arbeit eine umfassende Untersuchung durch, die die Nutzenpotenziale der MDA für eine anwendernahe und anforderungsgerechte Anwendungsentwicklung betrachtet. Es wird sowohl der Bedarf in der Anwendungsdomäne des Controllinginstrumentes VOFI (Vollständiger Finanzplan) erfasst als auch die Implementierung und Evaluation der Ergebnisse aus Sicht der Entwickler und Endanwender analysiert. Zudem werden die für Entscheider bedeutenden ökonomischen Konsequenzen durch die Verwendung von MDA systematisch aufgeführt.

Aus dem Inhalt

MDA: Grundlagen und Wiederverwendungsansätze

Investitionscontrolling: VOFI, SAP, Corporate Planner und Tabellenkalkulations-programme

mdaVOFI: Modellgetriebenes Konzept für VOFI, Entwicklung der VOFI-Produkt-familie

Evaluation: Entscheidersicht mit TCO-VOFI, Entwickler- und Anwendersicht

English

Application Development with Model Driven Architecture – In the Domain of Visualization of Financial Implications

Application development using Model Driven Architecture (MDA), which is standardized by Object Management Group (OMG), uses models as its first class citizen artefacts and allows high quality result in comparison with source code centric application development.

Dr. Dewanto explains in this book the potential of MDA for a user-oriented application development and explains how user requirements can be easily fullfilled by using MDA. He takes a real-world domain in investment planning with Visualization of Financial Implications (VOFI) and implements this domain step-by-step using the method of MDA. At the end of this book he summarizes the result of his research from user's and developer's perspective to show where the MDA potentials still need to be explored. Last but not least he shows an investment analysis using MDA in software development from a decision maker's view. He emphasizes in what cases it is financially worthwhile to utilize MDA in a small software development team.

Content

MDA: Basics and Software Reuse (Reference Modelling, Productline Software Engineering, Architecture and Patterns, Component Based Software Engineering)

Investment Planning: VOFI, SAP, Corporate Planner and Spreadsheet Applications

mdaVOFI: Model Driven Concept for VOFI, Development of VOFI Product Family

Evaluation: decision maker's perspective with TCO-VOFI (Total Cost of Ownership with VOFI), developer's and user's perspective

2006-10-03T07:36:00.000-07:00

Reuse or Rewrite AndroMDA Cartridges?

Someone asked me what is the best way to work with AndroMDA in case that the architecture (structure, naming, process, etc.) is different than the AndroMDA's one. Reuse all the cartridges as far as possible and extend them or rewrite them from scratch?

My opinions are as follow:

Think of a framework everytime you use AndroMDA. This includes the cartridges AndroMDA offers. When you are using frameworks you mostly don't want to rewrite them. You want to reuse and extend them. So, reuse and extend already available AndroMDA cartridges is the way to go.
If your team is only a small team never think of building your own architecture, thus you don't need to rewrite the cartridges. By building your own architecture (e.g. using your own directory structure, using your own naming convention, etc.) you mostly need to write your own cartridges which is costly. Remember that the developers of AndroMDA and AndroMDA cartridges are not beginners. They had many thoughts poured into the cartridges and most of them are experienced architects and developers. So you can be sure that the architecture of applications generated by AndroMDA cartridges are a stable architecture and has a good thought.
Never forget that AndroMDA is an Open Source project. If you think you have better ideas just join them and give them some inputs to make the available cartridges much more better!

So, when should we write our own cartridges?

In case that you are doing a re-engeneering project which means that you have all those source codes and you want to integrate AndroMDA cartridges slowly into the whole application development process you need to write your own cartridges. In this situation you can slowly "generate" some of the repeating codes by using your own cartridges. Already available AndroMDA cartridges will mostly miss this purpose. But again, if you write a new application reuse and extend available AndroMDA cartridges as far as you can.
Only build your own architecture and thus create your own cartridges if you and your team have the capacity and resources to do this.

Happy modeling,
Lofi.

2006-09-24T04:19:00.000-07:00

Next year conference...

Next year at OOP 2007 Frank and I will offer a session about MDA and product line engineering. In this session we'll show how to use MDA with product line techniques in a pragmatic way by using Open Source Java products. We'll underline the importance of Business Rules, so that we will be able to build a flexible solution for some domains which is based on the same business requirements.

This should be a practical session and not a theoretical one as often the case in product line sessions. I would also like to thank Gernot who made this session possible!

2006-08-20T07:06:00.000-07:00

The Heavyweight Champions are... Springframework and Hibernate?

There are a lot of argumentations exist trying to proof whether a combination of Springframework and Hibernate is still a "lightweight" or already a "heavyweight" champion. Please see following discussions in TSS for some of arguments:

My conclusions after working with Springframework and Hibernate in some of my projects are: yes, Springframework and Hibernate are already our heavyweight champions! Why?

It's getting on my nerves as I have to create SpringBeans by editing those Spring XML files. This is the same with Hibernate hbml files. I know there are some tools available (e. g. Spring and Hibernate plugins) to help me finish these annoying works. But still... at the end this is just the same as working with EJB 2.x with those deployment descriptors. You might say, I can use annotations. The problem is I still have to deploy in JDK 1.4.x. So annotations just won't work. I also know that Springframework 2.0 uses XML schema so the XML files are easier and shorter to create, but again, I hate creating XML files by hand and you?
Special for Springframework XML files and this is often the case: you need one XML file for remote client context, one XML file for local client context and one XML file for test? Gee, how many XML files should I write or copy and paste plus edit?
Hibernate should protect us from the database behind it. Is this true? Until a certain level yes, but if you try to work with Oracle and at the same time with MySQL you will still need to understand the differences between those databases! Do you know that Oracle always saves "" (empty string) as a null value? And this is not the case with MySQL! So welcome back to the relational database!
Do you know how many methods do we have in Hibernate just to persist or create a new object? What are these methods actually for: save, saveOrUpdate, persist, merge? Man, in SQL we just have one command: insert! Do we really need those different kind of methods just for a simple thing? Why can't we just say "save" and everything will be taken care by Hibernate?
I think you already heard a lot about architecture discussion to DTO or not. If not you can check out some interesting discussion in Springframework forum: Transfer Objects. You also can find the same discussion in TSS: Protecting the Domain Model. So, what's the hell why we use POJO if we still have to use DTO? You don't need to use DTO at all - many of us would loudly say, but what if we need to physically separate the tiers? In this case you will meet the most hated exception in Hibernate: Lazy Loading error if you are not carefully design your POJO! So sometimes we need DTO and sometimes not?
If you are by fall putting something wrong in the XML files - both Springframework and Hibernate - (not syntactically because your schema will help you in this case) and you get some errors because of these things. Good luck and have fun trying to find them!

So what are your options?

Accept those points above and be sure to know them best. Why not? You think, the combination of Springframework and Hibernate is still easier to use than EJB 2.x? More flexible than EJB 3.x? Yes, you are right. So, better to have a bad solution than no solution at all. Wow, you are what I call a pragmatic Java programmer.
Use AndroMDAwith the Springframework and Hibernate cartridges. Oh my, I don't want to have something to do with MDA and UML. But what are the advantages of AndroMDA? No need to create those damn XML files - both for Springframework and Hibernate - by hand. You have a standard architecture which will be strongly followed by everyone in your team (if you have one) all the time. Nothing like sometimes with DTO, sometimes without DTO. But still you need to implement those DTOs! Yes, but at least you have the skeletons created for you.
Build your own Dependency Injection and your OR mapper framework which are far better than Springframework plus Hibernate and don't forget at the end you should put them as Open Source products and release them through TSS news :-) So we all can admire your new products: oooh a new very easy framework but also it can support any complex situations (= all you can eat framework - and yes, Springframework is probably getting in this direction too. Of course you don't need to use everything but... we have that, we have this, ... You know what I mean).

It seems that using the option number 2 you will get back those "lightweight" Springframework with Hibernate (no XML files - they will be generated and we always use the same architecture everywhere)? It could be. With the price of using UML? Is this still "lightweight" or we just move our weight somewhere else? At the moment I prefer to use the option number 2 as I feel that I have lot more advantages in comparison of using the option number 1 or 3. But this should not be a general case and should be proven case by case!

Allright, at the end I admit that there are actually no "heavyweight" or "lightweight" frameworks, everything are relative to what exist and to what you know. In any case just take one of your options above and try to solve the problems you need to solve for your customers.

Happy coding and greets,
Lofi.

2006-08-20T06:37:00.000-07:00

The most interesting discussion in year 2005 I've followed and joined sofar about MDA and the future of Java is this one at TheServerSide.com: Beyond Java. More than 760 threads... with many interesting and great ideas...

2006-08-17T13:21:00.000-07:00

Happy Anniversary Indonesia!
p.f. 17 August 2006 - 61 years

FYI: Java island is located in Indonesia... so if you want to learn Java language you need to know Indonesian language first :-)

This should be your first exercise...

Selamat Ulang Tahun Kemerdekaan Indonesia yang ke 61! Semoga selalu panjang umur! Untuk membaca pidato Presiden RI, silahkan untuk melihat artikel ini di KOMPAS: Pidato Presiden 17 Agustus 2006.

2006-08-17T12:05:00.000-07:00

Jorn Bettin has written this comment on the "Standardisation of Model Driven Approach":

Also, beyond the realm of MDA, in relation to model driven approaches and the use of domain-specific languages in general, there is the question of when and to what degree will standardisation occur. Usually the more domain-specific a language can be made, the more value it adds. Yet, the closer a domain-specific language gets to capturing part of the competitive edge of an organisation, the less incentive for industry wide "standardisation".

From my point of view standardisation will only happen if we could get a direct positive impact from it. So, this is actually very pragmatic. A very good example is the use of AndroMDA. I could imagine that there are a lot of organisations out there - which are all the user of AndroMDA - which have standardised their "DSL" based on AndroMDA DSL elements like Entity, Service, tagged values, etc. Why? Because you get directly benefits from it. You can generate your codes easily when you use AndroMDA DSL.

So, just a specification will not help to standardise anything (or at least it will take very long = OMG). I always take the example of JCP (Java Community Process). You need 3 components to be able to standardise APIs:
- Specification
- Reference Implementation
- Test Compatibility Kit

... and this is not the case with OMG. No reference implementation, no test compatibility kit. IMO, Open Source project like AndroMDA could bring the standardisation a step further. Just like succesful Open Source projects Hibernate, Spring, Struts, etc. which are de-facto standard and not de-jure standard.

2006-07-26T11:59:00.000-07:00

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