Developing client applications

To call a deployed ruleset, you must use the public API to start a rule session from your client application. You can create a client application in Rule Designer by using a client project for decision service or a client project for RuleApps. A client project is a predefined project for Eclipse that contains execution code to call a ruleset that is contained in a RuleApp on Rule Execution Server.

Execution components
Execution components are components that enable the execution of a ruleset by the execution unit (XU). You choose between execution components depending on the ruleset deployment and execution platform, on the execution pattern, and on the possible use of EJB.
Execution patterns
Rule Execution Server supports synchronous execution patterns and asynchronous messaging through the Java™ Message Service (JMS) API.
Rule sessions
A rule session is a runtime connection between a client and a rule engine. Rule sessions use rule engine resources.
Message-driven rule beans
A message-driven rule bean, or MDB, is an enterprise bean that Java EE applications use to process messages asynchronously.
Setting up ruleset execution traces
You can activate traces of ruleset execution by using a specific application programming interface (API). You can start from the provided code sample to write your own code.
Ruleset interceptors
You can implement a ruleset interceptor on rule sessions to make ruleset selection depend on certain events that involve modified RuleApp or ruleset properties.
Ruleset parsing and the ruleset cache
Rulesets are parsed synchronously or asynchronously. With asynchronous parsing, which is set by default, execution of a new deployed version of a ruleset is not delayed by parsing. You can use a property to set ruleset parsing to synchronous.
RuleApp execution code generators
You can use code generators to create ruleset execution code for your Eclipse client projects.
Creating a client for Rule Execution Server
To execute rulesets in Rule Execution Server, you must create session-type-specific client projects. In Rule Designer, you can either create client projects for decision service, or client projects for RuleApps. You can modify the provided execution code generators and create your own. You can also call rulesets through stateless rule sessions or through message-driven rule beans.
Executing rules by using the REST service
Decision Server provides a Representational State Transfer (REST) service for ruleset execution. You can use it to execute rulesets through the HTTP protocol by using the XML or the JSON format.
JNDI bindings
Rule Execution Server supports local and remote JNDI bindings, and local and remote EJB bindings.