/*! ******************************************************************************
*
* Pentaho Data Integration
*
* Copyright (C) 2002-2016 by Pentaho : http://www.pentaho.com
*
*******************************************************************************
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************/
package org.pentaho.di.trans.steps.rules;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import org.drools.KnowledgeBase;
import org.drools.KnowledgeBaseFactory;
import org.drools.builder.KnowledgeBuilder;
import org.drools.builder.KnowledgeBuilderFactory;
import org.drools.builder.ResourceType;
import org.drools.definition.KnowledgePackage;
import org.drools.io.Resource;
import org.drools.io.ResourceFactory;
import org.drools.runtime.ObjectFilter;
import org.drools.runtime.StatefulKnowledgeSession;
import org.pentaho.di.core.row.RowMetaInterface;
import org.pentaho.di.i18n.BaseMessages;
import org.pentaho.di.trans.step.BaseStepData;
import org.pentaho.di.trans.step.StepDataInterface;
import org.pentaho.di.trans.steps.rules.Rules.Row;
public class RulesAccumulatorData extends BaseStepData implements StepDataInterface {
private static Class<?> PKG = RulesAccumulator.class; // for i18n purposes
private RowMetaInterface outputRowMeta;
private RowMetaInterface inputRowMeta;
private KnowledgeBuilder kbuilder;
private KnowledgeBase kbase;
private List<Object[]> results;
private String ruleString;
private List<Row> rowList = new ArrayList<Row>();
private List<Row> resultList = new ArrayList<Row>();
public String getRuleString() {
return ruleString;
}
public void setRuleString( String ruleString ) {
this.ruleString = ruleString;
}
public String getRuleFilePath() {
return ruleFilePath;
}
public void setRuleFilePath( String ruleFilePath ) {
this.ruleFilePath = ruleFilePath;
}
private String ruleFilePath;
public void setOutputRowMeta( RowMetaInterface outputRowMeta ) {
this.outputRowMeta = outputRowMeta;
}
public RowMetaInterface getOutputRowMeta() {
return outputRowMeta;
}
public void initializeRules() {
// To ensure the plugin classloader use for dependency resolution
ClassLoader orig = Thread.currentThread().getContextClassLoader();
ClassLoader loader = getClass().getClassLoader();
Thread.currentThread().setContextClassLoader( loader );
Resource ruleSet = null;
if ( ruleString != null ) {
ruleSet = ResourceFactory.newReaderResource( new StringReader( ruleString ) );
} else {
ruleSet = ResourceFactory.newFileResource( ruleFilePath );
}
kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
kbuilder.add( ruleSet, ResourceType.DRL );
if ( kbuilder.hasErrors() ) {
System.out.println( kbuilder.getErrors().toString() );
throw new RuntimeException( BaseMessages.getString( PKG, "RulesData.Error.CompileDRL" ) );
}
Collection<KnowledgePackage> pkgs = kbuilder.getKnowledgePackages();
kbase = KnowledgeBaseFactory.newKnowledgeBase();
// Cache the knowledge base as its creation is intensive
kbase.addKnowledgePackages( pkgs );
// reset classloader back to original
Thread.currentThread().setContextClassLoader( orig );
}
public void initializeInput( RowMetaInterface _inputRowMeta ) {
if ( _inputRowMeta == null ) {
BaseMessages.getString( PKG, "RulesData.InitializeColumns.InputRowMetaIsNull" );
return;
}
this.inputRowMeta = _inputRowMeta;
}
public void loadRow( Object[] r ) throws Exception {
// Store rows for processing
Map<String, Object> columns = new Hashtable<String, Object>();
for ( String field : inputRowMeta.getFieldNames() ) {
columns.put( field, r[inputRowMeta.indexOfValue( field )] );
}
rowList.add( new Row( columns, true ) );
}
public List<Row> getResultRows() {
return resultList;
}
public void execute() throws Exception {
if ( kbase != null ) {
StatefulKnowledgeSession session = kbase.newStatefulKnowledgeSession();
for ( Row row : rowList ) {
session.insert( row );
}
session.fireAllRules();
Collection<Object> oList = session.getObjects( new ObjectFilter() {
@Override
public boolean accept( Object o ) {
if ( o instanceof Row && !( (Row) o ).isExternalSource() ) {
return true;
}
return false;
}
} );
for ( Object o : oList ) {
resultList.add( (Row) o );
}
session.dispose();
}
}
/**
* Get the list of rows generated by the Rules execution
*
* @return List of rows generated
*/
public List<Object[]> fetchResults() {
return results;
}
public void shutdown() {
}
}