KIE provides a knowledge-centric API, where rules and processes are first class citizens. The majority of KIE API is considered stable and should not change, experimental classes and APIs will be marked as such.

The most common interfaces you will use are:

• org.kie.api.KieBase
• org.kie.api.runtime.KieSession
• org.kie.api.runtime.StatelessKieSession
• org.kie.api.runtime.KieContainer
• org.kie.api.builder.ReleaseId
• org.kie.api.builder.KieScanner

Factory classes, with static methods, provide instances of the above interfaces. A pluggable provider approach is used to allow provider implementations to be wired up to the factories at runtime. The Factories you will most commonly use are:

• org.kie.api.KieServices
• org.kie.api.command.KieCommands
• org.kie.api.io.KieResources

Typical example of loading and using knowledge resources (rules, processes, etc) found on classpath. By convention the KIE API expects file META-INF/kmodule.xml which is a marker file and also enables additional configuration. For very basic usage the file can just contain <kmodule xmlns="http://www.drools.org/xsd/kmodule"/>:

  KieServices kieServices = KieServices.Factory.get();
  KieContainer kieContainer = kieServices.getKieClasspathContainer();
  KieSession kieSession = kieContainer.newKieSession();
  kieSession.insert(new Fibonacci(10));
  kieSession.fireAllRules();
  kieSession.dispose();

Package	Description
org.kie.api	Base KIE API classes.
org.kie.api.builder
org.kie.api.builder.model
org.kie.api.cdi
org.kie.api.cluster
org.kie.api.command
org.kie.api.concurrent
org.kie.api.conf
org.kie.api.definition	All classes to create definitions, as built by the KieBuilder from artifact resources, can be found here.
org.kie.api.definition.process	The classes that make up a Process definition.
org.kie.api.definition.rule	The classes that make up a Rule definition.
org.kie.api.definition.type
org.kie.api.event	Comprehensive event API for all parts of the platform.
org.kie.api.event.kiebase	Events emitted while updating the definitions in the KieBase.
org.kie.api.event.kiescanner	Events emitted by the KieScanner.
org.kie.api.event.process	Events emitted while process instances are executing.
org.kie.api.event.rule	Events emitted while rules are executing.
org.kie.api.fluent	Process Fluent API allows programmer to build an in memory representation of a bpmn file. This information can later be used to build a KIE resource and execute the process .
org.kie.api.internal.assembler
org.kie.api.internal.io
org.kie.api.internal.runtime
org.kie.api.internal.utils
org.kie.api.internal.weaver
org.kie.api.io	io library for working with Resources
org.kie.api.logger	Logger classes used to log the KieRuntime's execution.
org.kie.api.management
org.kie.api.marshalling	Marshalling classes are used to marshall and unmarshal StatefulKieSessions
org.kie.api.persistence
org.kie.api.persistence.jpa
org.kie.api.pmml
org.kie.api.project
org.kie.api.remote
org.kie.api.runtime	The runtime engine classes, including KieSession and StatelessKieSession.
org.kie.api.runtime.conf
org.kie.api.runtime.manager
org.kie.api.runtime.manager.audit
org.kie.api.runtime.process	The process runtime classes.
org.kie.api.runtime.query
org.kie.api.runtime.rule	The rule runtime classes.
org.kie.api.task
org.kie.api.task.model
org.kie.api.time	Classes related to calendars and time.