AWG Blogs

  • Getting ADB Working for SPH-M840 - Had a SPH-M840 Galaxy Ring Virgin Mobile 3G Android version 4.1.2, attempting to install apps from Android Studio failed to detect device. Installed SAMSUN...
    7 months ago
  • How to check if I have write permissions to an Oracle table - SELECT CASE WHEN COUNT(*) > 0 THEN 'YES' ELSE 'NO' END AS PERMISSIONS FROM ( SELECT privilege FROM ( select * from dba_tab_privs where (grantee = 'MY_USE...
    7 months ago
  • JSF vs Struts 2 - JSF was designed in part by the authors of Struts to create a "Struts" that did a more accurate implementation of MVC (Struts is technically "Model 2") a...
    8 months ago
  • XML Beans vs JAXB - Seems XML Beans is superior: JAXB provides support for the XML schema specification, but handles only a subset of it; XMLBeans supports all of it. Also, by...
    1 year ago
  • Algorithms and OOP - In addition to DCI, "generic programming" as well as the move to functional programming appears to add nuance to the OOP notion of joining behavior with da...
    1 year ago
  • Flyweight vs Singleton - Implementations seems to be virtually identical, differing only in style, where the flyweight object is created and held by associated objects (containers:...
    1 year ago
  • init-param vs context-param - see http://javahash.com/difference-between-servlet-init-and-context-parameter/ for background. Gist: context-param variables are global and accessible thro...
    1 year ago
  • rbenv vs RVM - RVM is responsible not only for changing Ruby versions, but for installing rubies and managing gemsets, as well. ...Along with rbenv [to manage ruby versi...
    2 years ago

Monday, April 30, 2012

Middleman Pattern

The DCI paradigm, specifically the canonical example of the account transfer seems unnatural. If I'm not mistaken, in most business domains the act of transferring resources between entities is performed by a middleman entity. Behavior is no more injected into entities than are entry-level checking account clerks trained on the spot to make transfers to investment accounts (imagine this is a bank in the pre-computing days).

So I propose the "Middleman Pattern." The following is an example. Note: the example could be abstracted in that concrete classes could be decoupled via interface implementation and dependency injection.



Edit: See also suggestion of "money transferrer" at http://pettermahlen.com/2010/09/10/dci-architecture-good-not-great-or-both/

Tuesday, April 24, 2012

SharePointMVC Note

When following the Deployment.docx, the instructions say to put the DLLs in the SharePoint website _app_bin. Well, I had to also put the web app DLL in the SharePoint website bin folder to get it working; otherwise I'd get the error: Could not load type 'SampleWebApplication.xxxxxx'.   at System.Web.UI.TemplateParser.GetType(String typeName, Boolean ignoreCase, Boolean throwOnError)
   at System.Web.UI.TemplateParser.ProcessInheritsAttribute(String baseTypeName, String codeFileBaseTypeName, String src, Assembly assembly)
   at System.Web.UI.TemplateParser.PostProcessMainDirectiveAttributes(IDictionary parseData)

Sunday, April 15, 2012

UML Aggregation Vs DDD Aggregate

The same root term "Aggregate" in DDD does not correspond to the UML "Aggregation" notation (filled diamond).

DDD use of root term "Aggregate":
OrderLines have no reason to exist without their parent Order, nor can they belong to any otherOrder. In this case, Order and OrderLines would probably be an Aggregate, and the Order would be the Aggregate Root