Main Class as follows

 

package com.sample;

 

import java.io.InputStreamReader;

import java.io.Reader;

 

import org.drools.RuleBase;

import org.drools.RuleBaseFactory;

import org.drools.WorkingMemory;

import org.drools.compiler.PackageBuilder;

import org.drools.rule.Package;

 

/**

 * This is a sample file to launch a rule package from a rule source file.

 */

public class DroolsTest1 {

 

    public static final void main(String[] args) {

        try {

           

            //load up the rulebase

            RuleBase ruleBase = readRule();

            WorkingMemory workingMemory = ruleBase.newWorkingMemory();

           

            //go !

            Message message = new Message();

            message.setOp1(2);

            message.setOp2(2);

            workingMemory.assertObject( message );

            workingMemory.fireAllRules();  

           

           

        } catch (Throwable t) {

            t.printStackTrace();

        }

    }

 

    /**

     * Please note that this is the "low level" rule assembly API.

     */

      private static RuleBase readRule() throws Exception {

            //read in the source

            Reader source = new InputStreamReader( DroolsTest1.class.getResourceAsStream( "/Sample1.drl" ) );

           

            //optionally read in the DSL (if you are using it).

            //Reader dsl = new InputStreamReader( DroolsTest.class.getResourceAsStream( "/mylang.dsl" ) );

 

            //Use package builder to build up a rule package.

            //An alternative lower level class called "DrlParser" can also be used...

           

            PackageBuilder builder = new PackageBuilder();

 

            //this wil parse and compile in one step

            //NOTE: There are 2 methods here, the one argument one is for normal DRL.

            //builder.addPackageFromDrl( source );

            builder.addPackageFromXml( source );

 

            //Use the following instead of above if you are using a DSL:

            //builder.addPackageFromDrl( source, dsl );

           

            //get the compiled package (which is serializable)

            Package pkg = builder.getPackage();

           

            //add the package to a rulebase (deploy the rule package).

            RuleBase ruleBase = RuleBaseFactory.newRuleBase();

            ruleBase.addPackage( pkg );

            return ruleBase;

      }

     

      public static class Message {

            int op1 ;

            int op2;

            /**

             * @return the op1

             */

            public int getOp1() {

                  return op1;

            }

            /**

             * @param op1 the op1 to set

             */

            public void setOp1(int op1) {

                  this.op1 = op1;

            }

            /**

             * @return the op2

             */

            public int getOp2() {

                  return op2;

            }

            /**

             * @param op2 the op2 to set

             */

            public void setOp2(int op2) {

                  this.op2 = op2;

            }

           

      }

   

}

 

It’s in src/ java /com/ com.sample package

 

The sample1.drl file in src/ rules/Sample.drl is as follows

 

<?xml version="1.0"?>

<rule-set name="BusinessRulesSample"

          xmlns="http://drools.org/rules"

          xmlns:java="http://drools.org/semantics/java"

          xmlns:xs="http://www.w3.org/2001/XMLSchema-instance"

          xs:schemaLocation="http://drools.org/rules rules.xsd

                             http://drools.org/semantics/java java.xsd">

 

  <!-- Code for Drools Article (c)www.firstpartners.net 2005 -->

 

  <!-- Import the Java Objects that we refer to in our rules --> 

  <java:import>java.lang.Object</java:import>

  <java:import>java.lang.String</java:import>

  <java:import>com.sample.DroolsTest1.*</java:import>

 

     

  <java:functions>

      public void printValues(int i, int j)

      {

            System.out.println("hi"+i+j);

      }

  </java:functions>

 

 

  <!-- Check for XYZ Corp--> 

  <rule name="XYZCorp" >

 

      <!-- Parameters we can pass into the business rule -->

    <parameter identifier="message">

      <class>com.sample.DroolsTest1.Message</class>

    </parameter>

 

      <!-- Conditions or 'Left Hand Side' (LHS) that must be met for business rule to fire -->

     

     

      <java:condition>message.getOp1()==2</java:condition> 

      !-- What happens when the business rule is activated -->

    <java:consequence>

        printValues(message.getOp1(),message.getOp2());

    </java:consequence>

  </rule>

 

</rule-set>

 

 

When I run the program I will get the following error. If I change  addPackageFromXml to addPackageFromDrl the error is same . So please help me in this

 

 

(null: 7, 74): cvc-elt.1: Cannot find the declaration of element 'rule-set'.

org.drools.compiler.DroolsParserException

      at org.drools.compiler.PackageBuilder.addPackageFromXml(Unknown Source)

      at com.sample.DroolsTest1.readRule(DroolsTest1.java:55)

      at com.sample.DroolsTest1.main(DroolsTest1.java:21)

 

 

Thanks & Regards

Shilpa