/*
* JBoss, the OpenSource J2EE webOS
*
* Distributable under LGPL license.
* See terms of license at gnu.org.
*/
package org.drools.examples.sudoku.rules;
import org.drools.KnowledgeBase;
import org.drools.KnowledgeBaseConfiguration;
import org.drools.KnowledgeBaseFactory;
import org.drools.builder.KnowledgeBuilder;
import org.drools.builder.KnowledgeBuilderFactory;
import org.drools.builder.ResourceType;
import org.drools.io.ResourceFactory;
public class DroolsUtil {
private static DroolsUtil INSTANCE;
private DroolsUtil() {
}
public static DroolsUtil getInstance() {
if ( INSTANCE == null ) {
INSTANCE = new DroolsUtil();
}
return INSTANCE;
}
public KnowledgeBase readRuleBase(String drlFileName) throws Exception {
//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...
KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
//this will parse and compile in one step
kbuilder.add( ResourceFactory.newClassPathResource( drlFileName,DroolsSudokuGridModel.class),
ResourceType.DRL );
//Use the following instead of above if you are using a DSL:
//builder.addPackageFromDrl( source, dsl );
//add the package to a rulebase (deploy the rule package).
KnowledgeBaseConfiguration kbaseconfiguration = KnowledgeBaseFactory.newKnowledgeBaseConfiguration();
kbaseconfiguration.setProperty( "drools.removeIdentities",
"true" );
KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase( kbaseconfiguration );
// RuleBase ruleBase = RuleBaseFactory.newRuleBase( RuleBase.RETEOO,
// conf );
kbase.addKnowledgePackages( kbuilder.getKnowledgePackages() );
return kbase;
}
}