Sunday, October 25, 2009

Best of this Week Summary 19 October - 25 October 2009

Sunday, October 18, 2009

Best of this Week Summary 12 October - 18 October 2009

  • Last week was Oracle Open World 2009. Beside for Oracle DBMS and SOA specialists, these days the event is definitely also very relevant to Java professionals because of Oracle's (almost official) acquisition of Sun this year. Here's a set of relevant information from OOW:

    • The keynote on sunday which also describes the plans Oracle has with Java, MySQL and Sun hardware

    • James Gosling explaining to the developer audience what Sun was doing, what the scale is of Java activity around the world and across technology platforms.

    • The Dutch software company Amis also did quite a few presentations at OOW. Some of those presentations were already online before they were actually presented! All were interesting:

      • Good overview of what will be in the Patch Set 1 for the Oracle Fusion Middleware 11g stack, including JSF and ADF (mobile!). It's more than a patch!

      • Edition Based Redefinition (EBR): "Every database object (well, almost every database object - not tables!) can have different implementations/incarnations/versions in various editions. The object versions are all in the same schema - they only differ in the Edition they are created in."
        So no more direct table access! No big bang needed anymore. Challenges: what if a mandatory column is removed or added from the current EBR view (answer: special triggers). Including 2 suggestions for best practices.

      • XML processing/design tips.

      • This "session introduces SOA and the new Oracle SOA Suite 11g to the realm of database professionals from which it sometimes seems so far removed. What are the key SOA concepts and objectives? What is at the heart of Oracle SOA Suite 11g: composite applications, BPEL PM, and the mediator. The session shows how SOA services can be leveraged from the database, from triggers, PL/SQL units, or even SQL and how the database can publish events to the event delivery network. It covers how the SOA infrastructure can access the database, primarily using Oracle Database and Oracle Advanced Queueing adapter and how database developers can help in doing so efficiently. It ends with hints for applying SOA concepts to "normal" database development."

        Bit oriented at the database professional, but still interesting for those who want to stay up to date with Oracle's DMBS possibilities. And a bit scary too: it is possible in 11g to make webservice calls and publish them from the database(!). For example from PL/SLQ and put a webservice in front of PL/SQL... I haven't come up with a practical situation where you'd want to do this from an architectural point of view: large risk to getting tightly coupled systems and dependencies. If you have heavily invested (i.e built) in PL/SQL, it might be a valid option though.


  • There is currently a renewed focus on the role of code generation in developing enterprise Java applications. Springsource recently released Roo, Skyway Software released Skyway Builder Community Edition version 6.3 and Blu Age released M2Spring. What should the software architects and developers look for in a Code Generation framework?

  • Seven Wicket Do's and Don'ts.

Sunday, October 11, 2009

Best of this Week Summary 05 October - 11 October 2009

  • A quite in-depth article on creating highly-scalable components in Java. Described are the ideas used to create the concurrent Java components in the Amino Library Project (a set of concurrent building blocks).

  • Another SOA Design Pattern sample chapter from Thomas Erl' book "SOA Design Patterns": "Service Governance Patterns, comprising a number of 8 patters. Compatible Change and Version Identification deal with service versioning. Termination Notification addresses the final phase of a service, it’s retirement. Service Refactoring explains how to deal with changing service contracts. Service Decomposition, Proxy Capability, and Decomposed Capability include techniques needed to express coarse-grained services through multiple fine-grained ones. Distributed Capability helps increasing service scalability through processing deferral."

  • To ESB or not to ESB? Including a nine points checklist. Note that the article is from the creator of Mule (a lightweight ESB). Check also the comments here.

  • Interesting hack to reduce startup latency for mobile devices with HTML5: put the Javascript code in comments (thus /* */), such that is immediately downloaded but not evaluated. Then to load it when needed, parse the text, strip out the comment-tags & do an eval().

Sunday, October 4, 2009

Best of this Week Summary 28 September - 04 October 2009

  • "Tony Hoare introduced Null references in ALGOL W back in 1965 “simply because it was so easy to implement”, says Mr. Hoare. He talks about that decision considering it “my billion-dollar mistake”. Tony Hoare, is a British computer scientist, probably best known for the development in 1960, at age 26, of Quicksort. He also developed Hoare logic, the formal language Communicating Sequential Processes (CSP), and inspired the Occam programming language."

  • "Peter Thomas has updated his web framework performance benchmark with Grails and Tapestry. Apache Wicket still leads the best of breed frameworks in terms of request times and memory usage." Other observations:

    • Grails was far more productive than Tapestry 5. This was mainly due to the documentation quality of Grails compared to the scattered and not very well organized Tapestry documentation.

    • Ease of writing custom tag-libraries is IMO one of the best things about Grails.

    • Grails still has some way to go in terms of performance. I am told that significant performance optimizations for GSP will make it into 1.2

    • Session usage of the Seam + JSF combination is significantly higher compared to all the rest, around 760 KB per session."


  • "At the JVM Languages Summit, Josh Bloch expressed his concern about what he called the "semantic gap" between the source code we write and its performance at runtime: As performance improves, our ability to predict the performance consequences of our source code degrades." Feedback from people on this subject can also be found here.

  • "Mckoi Distributed Database (MckoiDDB) is a database system used by software developers to create applications that store data over a cluster of machines in a network. It is designed to be used in online environments where there are very large sets of both small and big data items that need to be stored, accessed and indexed efficiently in a network cluster. The focus of the MckoiDDB architecture is to support low latency query performance, provide strong data consistency through snapshot transaction isolation, and provide tools to manage logical data models that may change dramatically in physical network environments that may experience similar dramatic change.
    MckoiDDB is written in 100% Java and runs on any operating system that supports Java 1.6. MckoiDDB is released under the GPLv3 open source license."