Third Party Data Access

ILOG JRules can be integrated with most data access patterns with little or no additional infrastructure code. This section describes a number of DAO (Data Access Objects) products and approaches, and provides an example of one of these: JDO.

Based on architectural decisions, data access must be customized for use with ILOG JRules. For a simple scenario, customization may include:

DAO Products

There are a number of commercial or Open Source persistence frameworks for Java. The following tables provide a brief overview of some of these tools. The tools are split into enabling technologies and Integrated Development Environments (IDEs).

Sample Code for Integration using JDO

To integrate JRules with third party data, you need to add the relevant code to your application. For example, to integrate third party data using JDO, you would need to add the following code:

import javax.jdo.JDOHelper;
import javax.jdo.PersistenceManager;
import javax.jdo.PersistenceManagerFactory;
import javax.jdo.Transaction;
import javax.jdo.Query;
 
...
 
Properties p = ... // read propertes to get the JDO configuration
PersistenceManagerFactory pmf = JDOHelper.getPersistenceManagerFactory(p);
PersistenceManager pm = pmf.getPersistenceManager();
pm.currentTransaction().begin();
 
Query q = pm.newQuery(Order.class, "ID == 123456");
Collection results = (Collection) q.execute();
 
Order order = (Order)results.get(0);
 
// then use this order with a rule session
try {
// get a session provider, open a rule session
// execute the ruleset on this order (inout parameter)
// let us suppose this order is modified by the rules 
 
pm.makePersistent(order);
pm.currentTransaction().commit();
 
} catch (AnythingBadOccursException e) 
{
 
     pm.currentTransaction().rollback();
}
 
pm.close();
pmf.close();

Related Concepts