My application handles multiple request but the rules in my knowledge session are executed by single thread only. For eg: Thread 1 and Thread 2 enters the knowledge session with the gap of 2millisec But Thread 1 executes its own rules and even the rules for Thread 2 is executed by Thread 1. Imagine if there are 1000 request which means the rules for each requests will be executed by only a 1 Thread?
Is there any way where in DROOLS where we can prevent this and ensure that the rules are executed by multiple Threads?
Below is a small sample test I tried:
Java Class:
import java.math.BigDecimal;
import org.drools.KnowledgeBase;
import org.drools.KnowledgeBaseFactory;
import org.drools.builder.KnowledgeBuilder;
import org.drools.builder.KnowledgeBuilderError;
import org.drools.builder.KnowledgeBuilderErrors;
import org.drools.builder.KnowledgeBuilderFactory;
import org.drools.builder.ResourceType;
import org.drools.io.ResourceFactory;
import org.drools.runtime.StatefulKnowledgeSession;
import org.drools.runtime.rule.WorkingMemoryEntryPoint;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class DJ_Test {
public static void main(String[] args) {
try {
System.out.println("In main");
// load up the knowledge base
KnowledgeBase kbase = readKnowledgeBase();
final StatefulKnowledgeSession ksession = kbase.newStatefulKnowledgeSession();
final WorkingMemoryEntryPoint entry =ksession.getWorkingMemoryEntryPoint("RequestStream");
final Object obj_1= new Object();
Thread t1 = new Thread(){
public void run(){System.out.println(Thread.currentThread().getName() + " is running");
entry.insert(obj_1);
ksession.fireAllRules();
System.out.println(Thread.currentThread().getName() + " is terminated");
}
};
final Object obj_2= new Object();
Thread t2 = new Thread(){
public void run(){
try{
Thread.sleep(8000);
}catch(Exception e){
}
System.out.println(Thread.currentThread().getName() + " is running");
entry.insert(obj_2);
ksession.fireAllRules();
System.out.println(Thread.currentThread().getName() + " is terminated");
}
};
t1.start();
t2.start();
} catch (Throwable t) {
t.printStackTrace();
}
}
private static KnowledgeBase readKnowledgeBase() throws Exception {
/* KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
kbuilder.add(ResourceFactory.newClassPathResource("rulesFlow.bpmn"), ResourceType.BPMN2);
kbuilder.add(ResourceFactory.newClassPathResource("KansasSalesTax.drl"), ResourceType.DRL);
kbuilder.add(ResourceFactory.newClassPathResource("MissouriSalesTax.drl"), ResourceType.DRL);
kbuilder.add(ResourceFactory.newClassPathResource("SalesTax.drl"), ResourceType.DRL);
KnowledgeBuilderErrors errors = kbuilder.getErrors();
if (errors.size() > 0) {
for (KnowledgeBuilderError error: errors) {
System.err.println(error);
}
throw new IllegalArgumentException("Could not parse knowledge.");
}
KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());
return kbase;*/
ClassPathXmlApplicationContext serviceContext = new ClassPathXmlApplicationContext( "droolsContext.xml" );
return (KnowledgeBase) serviceContext.getBean("kbase1");
}
public static class DJ_Message {
public static final int thread_1 = 1;
public static final int thread_2 = 2;
private String message;
private int status;
public String getMessage() {
return this.message;
}
public void setMessage(String message) {
this.message = message;
}
public int getStatus() {
return this.status;
}
public void setStatus(int status) {
this.status = status;
}
}
}
DRL file
package com.sample
import com.sample.DroolsTest.Message;
//global CepService cepService;
declare Object
@role( event )
end
rule "rule_1"
salience 100
when
$o : Object() from entry-point RequestStream
then
System.out.println( "Rule 1 fired by " + Thread.currentThread().getName() );
Thread.sleep(5000);
end
rule "rule_2"
salience 80
when
$o : Object() from entry-point RequestStream
then
System.out.println( "Rule 2 fired by " + Thread.currentThread().getName() );
Thread.sleep(5000);
end
rule "rule_3"
salience 60
when
$o : Object() from entry-point RequestStream
then
System.out.println( "Rule 3 fired by " + Thread.currentThread().getName() );
//cepService.executingThread1();
end
rule "4"
when
Message( status == Message.GOODBYE, myMessage : message )
then
System.out.println( myMessage );
//cepService.executingThread2();
end
