Thursday, December 24, 2009

Released TevereFlow, the first workflow engine with a Web Editor

Starting from December 22nd 2009 is available the new version of TevereFlow.

Tevere Flow is a light-weight Workflow engine built using the Java® technology. Just download it and create your process using the Web interface. You can use Tevere as embedded or as external engine by using the provided Web Services API.

Tevere was built using Roma Framework under the Romulus consortium an it's currently used in several production systems.

Main features:

  • Open Source Apache 2.0 license
  • Web User Interface using the Ajax technology
  • Stand-alone application: just download and start it
  • Fully Transactional supporting any RDBMS or db4o ODBMS
  • Set of built-in commands available (email, web service invocation, etc.)
  • Auto-resume of failure activities
  • User and profile management
  • Activities can be written in Java or using any supported scripting language such as Javascript and Ruby
  • Integration via Java APIs or WebService

Tuesday, December 22, 2009

Search on Freshmeat

After I've posted the last release 2.1.0 of Roma Meta Framework on Source Forge I tried to search the project by typing "Roma" in the search field of Freshmeat home page:

0 search results for: roma

What???? If I type "Roma Framework": the result is always 0 (zero) results but with the result table filled:

Maybe they require an exact search? Not properly, since if I try to search for "framework":

1941 search results for: framework

What kind of search is it?

Thursday, October 01, 2009

Terracotta as distributed DBMS? Bad idea!

Some months ago I have had a fucking genius idea about a new application. In order to start working to my idea I need to distributed at large tons of objects in several nodes around the Internet. After a deep research about all the best solutions available now I decided to try Terracotta.

Basically I need a real distributed Object repository so why don't create a simple Object DBMS virtually all in RAM and let to Terracotta most of the hard work?
  1. Handle the cache on nodes
  2. Manage the object/page fault in a transparent way for the application
  3. Share the load among nodes
  4. And obviously: read/write objects in persistent way
So I've developed a very simple library that uses the JDK 1.6+ TreeMap to collect data and to query them. I was surprised to discover how much terracotta makes a good job in hiding the dirty work and complexity of data distribution.

But before to think to use this piece of code in a production system I need to be sure that the objects became really persistent in ACID way. For this reason I developed some Test Cases as microbenchmarks to see the real throughtput and if data are written in synchronous way to the disk. This was my test using the library I wrote:

UserDatabase db = ServerNode.getInstance().connect("petshop", null, null);
clazz = db.getClazz("Animal");

for( int i = 0; i < 100000; ++i ){
UserObjectTransient object = clazz.createObject();

object.setValue("name", "Gaudi");
object.setValue("description", "My crazy ferret!");
object.setValue("from", "Barcelona, Spain");

Pretty nice, don't you? The Terracotta server instance was on a remote server with 1GB of heap and enought bandwitch available and the client runned on my laptop. Yes I know, this is a microbenchmark and can't tell to me the performance in all the scenarios. But to go on on my experiments I needed to know if I was totally crazy or if there was a way to build a robust & scalable solution to satisfy my needs.

Well, in this test my library + Terracotta (after some tuning by reading the documentation and the forum) are able to write around 190 objects per second. Not really bad for the first release and in comparison to a RDBMS solution. But I've stored just a dynabean with two properties... I remember in the past (about 8 years ago!) when I tried a real ODBMS (Orient ODBMS) it was able to store 100x of this solution using a 8-years-old hardware!

But the really bad news is another one: When the "for cycle 100.000" was finished and the application seemed to be succesfully ended I noted that the console had no control. The test was still running! After 10 seconds I killed the java process and counted the objects created (using the Terracotta console): 99.345!

Where are the 655 objects missed? Ok, probably I got wrong about ACID features. No, the Terracotta documentation tells ACID! But how it can be ACID if the client sends the objects to the server in asynchronous way?

I'm pretty confident that it would be exist in any point of configuration the real synchronous mode but even though it exists what about the performance? If this ASYNCHRONOUS solution was able for 190 obejcts/sec as throughtput the synchronous one must be much more slow!

These are the reasons why I abandoned this path. Terracotta surely fits well in traditional replication contexts and the product is really good on documentation, presentation, APIs, etc. But for my needs I have to continue in searching...

Monday, September 21, 2009

Remove the persistence layer at all to scale up?

In these days I'm working for a brand new idea that need to scale out (close to the infinite?) and after a lot of thoughts about its architecture I'm seriously evaluating to remove the persistence layer using a distributed in-memory cache, obviously with the "fail-over" feature: Terracotta.

Terracorra, under the hood, records all changes happened to the objects using BerkeleyDB. All is transparent to the application and on crash the server swaps to another one configured without interruption and leaving all objects consistent. Or, at least, it seems to be so.

Does anyone have never used Terracotta in a real-world application without a DBMS to store data?

Thursday, September 17, 2009

Roma Framework and the Virtual Objects

Yesterday night I've committed in the Roma's SVN (revision: 4479) source repository the first version of Virtual Objects. Virtual Objects are like POJO, but built dinamically just using a descriptor, in this case a XML file. The XSD is the same of Roma XML annotations but now allows to specify the field type and in future declaring inheritance and other stuff.

Action implementation can be written using any scripting language is supported by JSR 223, Javascript in primis.

Roma treats Virtual Objects in the same way of POJO, so you can define an Employee at the fly in this way:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<class xmlns="" xmlns:xsd=""
<area name="main" type="column">
<area name="fields" size="2" type="grid" />
<area name="actions" type="row" />
<field name="id" type="Integer" />
<field name="name" type="String" />
<field name="surname" type="String" />
<field name="born" type="Date" />
<field name="age" type="Integer">
<view enabled="false" />
<field name="salary" type="Float" />
<action name="refresh">
<action name="print">
<action name="login">
<event name="show">
Roma.fieldChanged(me, ["age"]);

And this is the result:
Note that changes to the XML files are loaded in real-time enabling a real productive development (and production why not) environment.

Monday, August 24, 2009

New Google Wave account

Yesterday I've received my Google Wave account as developer.

I've played for some minutes and it's really awesome even though I don't know no one that own it as well to play together with all the features!

Once returned from holidays I'll try to go deep to the APIs in order to know how to integrate it inside Roma Meta Framework and Romulus.

Wednesday, June 03, 2009

Wednesday, May 27, 2009

Scripting RAD tools such as Ruby on Rails and Grails can be really slow?

Tiago Fernandez in his blog reported some results about benchmarks using Java, JRuby, Groovy and Scala. I know: we can talk about benchmarks for days but in the Internet there are a lot of them and the performance problems of the scripting language is not a news.

Results show that Groovy is very slow in comparison to the pure Java and the Scala scripting language. This could be a serious reason to be worried when your application created with Grails or RoR goes in production...

So, why don't you use a real Java RAD tool like Roma Meta Framework? :-)

You can develop shortly without using a scripting language with the benefits of great refactoring support (Eclipse, Netbeans and IntelliJ are master on it) and performance and scalability!

The source:

Monday, May 25, 2009

Romulus at the Internet of Services 2009 conference

On June, 10th 2009 I will be in Brussels to present the Romulus demo at the "Internet of Services 2009" conference. Romulus project is scheduled in the afternoon. Below the agenda.

Group 2: June 10, 13:30 - 17:30

• Semantically enhanced SLA Negotiation (BREIN)
• Automated Service Level Agreement Management Framework - Adhoc Demonstrator (SLA@SOI)
• TEAM: Knowledge management in distributed software communities by applying semantic technologies (TEAM)
• Decentralized transactional collaborative drawing (SELFMAN)
• Romulus: your answer to improving productivity in Java Web Applications (ROMULUS)
• Edutain@Grid: A Service-Oriented Infrastructure for Future Real-Time Interactive Internet Applications (edutain@grid)

Tuesday, May 19, 2009

Luca in the first page of Google searching for "Java JSR"

Today Mara told me that searching "Java JSR" in Google (at least in the Italian version), in the first page compares my face and this blog... I've tried and is real! What nice thing :-)

Wednesday, May 06, 2009

Transparent DataNucleus enhancement at run-time

Today it has worked! In the last days I was working to avoid the enhancement phase in the building of Roma Framework projects. Yes. Until yesterday you needed to invoke the "persistence-compile" task in your Roma project and all the projects that contained persistent classes.

Furthermore pre-packaged modules such as ADMIN, USERS, MESSAGING and SCHEDULER-QUARTZ needed to self-execute the enhancement in order to put persistence capable classes inside the JAR. This was a mess if you needed to change the ORM binding since anything resided inside the JAR.

I have to check yet if run-time changes to the entity POJOs are auto-enhanced at the fly... If works the productivity would be speedup over and over again.

Thanks to Andy Jefferson of DataNucleus team in supporting my crazy requestes :-) The work tomorrow will be in changing all the wizards to support the new configuration. In few words the change consist in:
  1. Let to the PersistenceAspect to invoke the Enhancer at startup
  2. Create the file persistence.xml inside the src/META-INF folder.
Once everything works I'll commit in to the SVN trunk for the upcoming release 2.0.

Saturday, April 25, 2009

Romulus technical meeting in Madrid

Today has finished the 3-days technical meeting of Romulus. In the first day we've worked in the UPM (Universitad Politecnica de Madrid) class room.

For the second day Carlos Iglesias has organized the entire working day in Segovia, a beautiful city at about one hour from Madrid. We've worked inside a agritourism and eaten a lot of home made food. In the afternoon we have had the social roundtrip in the Segovia city. If you're in Madrid you can't not to visit Segovia! There are a lot of monuments in a so small city. The catedral, the Fortress and the Roman waterworks, all in perfect state. It seems they was built in the past year.

This morning we went back to the UPM class room in order to finish the last pending works and give the new action points. Asset Data is envolved in almost all the activities and I know that when I'm back to Italy a huge work expects me and my company for the next months.

Am I Tired? Not at all. Instead, I'm very excited to go back to work to the new Roma Meta Framework version 2.0 and contributing to the growth of Romulus consortium & technology.

Tomorrow is the last day. Luigi will take the flight in the early morning. Giordano and me, instead, will go to the Toledo city for a fast trip. Just the time to see the centre of the city, buy a tipical medieval sword for my house, having lunch with "Pulpo a la Gallega" and go back to Madrid for the our flight.

Bye bye Spain!

Wednesday, March 25, 2009

Released Roma Meta Framework 1.2.0: the latest 1.x version!

Today I've released the version 1.2.0 of Roma Meta Framework. This is the last 1.x version since starting by tomorrow I'll work to the next 2.0 implementing a lot of new ideas born in the last year.

Roma 2.0 will be not more compatible with 1.x but someone will provide a migration tool that will help to port current/old applications to the new one. Soon a presentation of the main new ideas.

A huge work is waiting for me. For this reason let me enjoy the 1.2.0, just for today!

Below the main addictions and improvements of the 1.2.0:

CORE module:
- Created CollectionWrapper domain classes to display collections in better way. Now there are two implementations: TableWrapper<> and MasterDetailWrapper<>. See the Handbook.pdf to know more
- Disable the class checking for hot-updates. Useful in production
- New refresh of multiple fields in one shot or the entire object
- Resolved bug on the session management under WebLogic AppServer

VIEW module:
- New "URL" rendering mode to embed static and dynamic content in forms. Now you can embed HTML files, JSP files and Web sites at all
- Managed render of collections and arrays using the "OBJECTEMBEDDED" mode
- Resolved a bug on table ordering
- Improved Echo2 Table component in order to support the change of the color of the column headers
- Updated to the stable version 2.1.0 of Echo2

- Updated to the stable version 1.1.0 of DataNucleus

ADMIN module:
- Fixed management of Info and InfoCategory instances
- Created CRUD of GenericValue

JETTY module:
- Integrated new release of Jetty 6.1.5
- The script under the user project script/ (and .bat) now works

CRUD wizard module:
- CRUD now generate also: factory class (DDD), repository class (DDD) and an entry in the package.jdo file if any

Thursday, March 12, 2009

Luca, Roma e Romulus: tre amici su Mokabyte

Se non hai proprio nulla da fare, magari perchè stai usando Roma e quindi hai finito prima il tuo lavoro :-), leggiti questa intervista fatta dalla rivista Java più letta in italia: Mokabyte

Tuesday, January 27, 2009

JavaDay III edition

The 3rd edition of the JavaDay is gone. 1.400 visitors: 1225 workers, 363 student, 74 unemployeed.

The AssetData's stand has received more than 300 curricula. For this reason I've take the decision to build from stratch an application to collect all them using Roma Meta Framework. After 1 hour it worked, but the GUI is not yet very intuitive...

During the event I encounter Paolo, a very old collegue of about 12 years ago in my second project for the IRI group. I have seen again a lot of other past collegues and friends...

I love the JavaDay also for this reason :-)

(photo by Valerio Casale)

Wednesday, January 07, 2009

Recupero crediti? Non ho il fisico

Da quando sono diventato uno pseudo-commerciale e seguo i clienti direttamente mi capita, ahimè, di occuparmi anche di RECUPERO CREDITI. Eggià. Clienti che chiedono servizi, consulenze, prodotti e poi dopo mesi arrancano sempre le solite scuse. Le 5 migliori del 2008 sono state:
  1. La nostra banca si è fusa in un gruppo più grande e non riusciamo a fare i bonifici!
  2. La società è in ottima salute...Ma abbiamo problemi di cassa
  3. I nostri clienti non ci hanno pagato...
  4. La fattura è stata smarrita (fu consegnata a mano!)
  5. Abbiamo deciso che vi pagheremo solo se riusciamo a rivenderlo al cliente finale (dopo 3 mesi dalla consegna)
Diciamo che non ho propriamente il fisico per fare "recupero crediti". E quindi ecco il motivetto che mi accompagnerà nel 2009:

"Soffro lo strees
io soffro lo stress
sono stanco e fuori forma
vado in giro per clienti
a recuperare i pagamenti
ci deve essere un errore!!!"