techno.blog("Dion")

I enjoyed the article from IBM on Service Data Objects.

Things have gone a little quiet on the SDO front for awhile, so it is good to see example code.

It is interesting to look at how the API is used:

// Get the SDO DataGraph from the DMS.
DataGraph employeeGraph = mediator.get(employeeName);
…
// Get the root object
DataObject root = employeeGraph.getRootObject();
…
// get the employee under the manager
employee = theManager.getDataObject(”employees.0″);

The API looks very generic. Similar to JDBC (get/set/Int/String etc).

The data graph that you are working with plays nicely with XML:

<?xml version="1.0" encoding="UTF-8"?>
<sdo:datagraph xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:company="http://com.example.company.ecore"
xmlns:sdo="commonj.sdo"
xmlns:sdo_1="http://www.eclipse.org/emf/2003/SDO">
<changeSummary>
<objectChanges key="#//@eRootObject">
<value xsi:type="sdo_1:EChangeSummarySetting"
featureName="department" dataValue="Board"/>
</objectChanges>
</changeSummary>
<company:Employee name="The Big Boss"
number="1" department="The new department" title="Mr."
manager="true">
<employees name="Terence Shorter" number="2"
department="The new department" title="Mr." manager="true">
<employees name="Miles Colvis" number="3"
department="The new department" title="Mr."/>
<employees name="John Datrane" number="4"
department="The new department" title="Mr."/>
</employees>
</company:Employee>
</sdo:datagraph>

The more I see of this, the more that I see SDO and JDO/The New Persistence API working together. SDO can be used on the service boundaries, and as ways to access data across services. But I still want to have an object model, in which I persist things, and for that I want to use a transparent persistence solution.