Hi, I am implementing rules engine into my project, I have been referring the many technical resources about jboss drools. I did implement some set of rules which are much more needed for my project. All of a sudden after I placed all the rules in the spreadsheet(.xls) file, and executed it, it shows me strange exceptions like this below. It was reading the xls file, creating .drl file, that also we can see, but it is showing the errors. Can anyone help me please on this, I am very much tried, could not able to resolve. I need a clue how to do that. This is my class, where I will have conditional parameters package com.dfs.dsa.rules; public class QuarterlyBonusRules { private Double attendancePercentage = null; public Double getAttendancePercentage() { return attendancePercentage; } public void setAttendancePercentage(Double attendancePercentage) { this.attendancePercentage = attendancePercentage; } public int getMinorCollisionDays() { return minorCollisionDays; } public void setMinorCollisionDays(int minorCollisionDays) { this.minorCollisionDays = minorCollisionDays; } public int getMajorCollisionDays() { return majorCollisionDays; } public void setMajorCollisionDays(int majorCollisionDays) { this.majorCollisionDays = majorCollisionDays; } private int minorCollisionDays; private int majorCollisionDays; private int bonusAmount = 11; private boolean violationAssessed = false; public int getBonusAmount() { return bonusAmount; } public void setBonusAmount(int bonusAmount) { this.bonusAmount = bonusAmount; } public boolean isViolationAssessed() { return violationAssessed; } public void setViolationAssessed(boolean violationAssessed) { this.violationAssessed = violationAssessed; } } Then I do have one test class to execute the rules package com.dfs.dsa.rules; import java.io.BufferedWriter; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileWriter; import java.io.IOException; import java.io.InputStream; import java.util.Collection; 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.decisiontable.InputType; import org.drools.decisiontable.SpreadsheetCompiler; import org.drools.event.rule.DebugAgendaEventListener; import org.drools.event.rule.DebugWorkingMemoryEventListener; import org.drools.io.ResourceFactory; import org.drools.runtime.StatefulKnowledgeSession; /** * This class will create a drl file from excel sheet and then execute the * rules. */ @SuppressWarnings("restriction") public class QBResult { public static final void main(final String[] args) { // Create knowledge builder final KnowledgeBuilder kbuilder = KnowledgeBuilderFactory .newKnowledgeBuilder(); // Create drl file from excel sheet InputStream is = null; try { is = new FileInputStream("c:/myeclipse/DroolsProject/src/QuarterlyBonusRules.xls"); } catch (FileNotFoundException e) { e.printStackTrace(); } // Create compiler class instance SpreadsheetCompiler sc = new SpreadsheetCompiler(); // Compile the excel to generate the (.drl) file StringBuffer drl = new StringBuffer(sc.compile(is, InputType.XLS)); // Insert dialect value into drl file drl.insert(drl.indexOf("DROOLS") + 40, "dialect \"mvel\"" + "\n"); // Check the generated drl file System.out.println("Generate DRL file is showing below–: "); System.out.println(drl); // writing string into a drl file try { BufferedWriter out = new BufferedWriter(new FileWriter( "QuarterlyBonusRules.drl")); out.write(drl.toString()); out.close(); } catch (IOException e) { System.out.println("Exception "); } // Wait before using the drl file in the next section. try { Thread.sleep(100); } catch (InterruptedException e) { e.printStackTrace(); } kbuilder.add(ResourceFactory.newFileResource(new File( "QuarterlyBonusRules.drl")), ResourceType.DRL); if (kbuilder.hasErrors()) { System.out.println("kbuilder has errors"); System.out.println(kbuilder.getErrors().toString()); } // get the compiled packages (which are serializable) final Collection pkgs = kbuilder.getKnowledgePackages(); final KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase(); kbase.addKnowledgePackages(pkgs); final StatefulKnowledgeSession ksession = kbase .newStatefulKnowledgeSession(); ksession.addEventListener(new DebugAgendaEventListener()); ksession.addEventListener(new DebugWorkingMemoryEventListener()); QuarterlyBonusRules qbr = new QuarterlyBonusRules(); qbr.setAttendancePercentage(new Double(0.75)); qbr.setMinorCollisionDays(0); qbr.setMajorCollisionDays(0); qbr.setViolationAssessed(false); ksession.insert(qbr); ksession.fireAllRules(); ksession.dispose(); System.out.println(qbr.getBonusAmount()); } } AFter executing the above program, here I am getting the error, and not able to rectify it SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder". SLF4J: Defaulting to no-operation (NOP) logger implementation SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details. Warning: Cannot read name ranges for Excel_BuiltIn__FilterDatabase_1 - setting to empty Warning: Cell at D21 not present - adding a blank Generate DRL file is showing below–: package DROOLS; //generated from Decision Table dialect "mvel" import com.dfs.dsa.rules.QuarterlyBonusRules; // rule values at B11, header at B6 rule "1" when qbr:QuarterlyBonusRules(attendancePercentage>=0.75) (minorCollisionDays>=0 && minorCollisionDays<=0); (majorCollisionDays>=0 && majorCollisionDays<=0); violationAssessed==false; then qbr.setBonusAmount(150); end // rule values at B12, header at B6 rule "2" when qbr:QuarterlyBonusRules(attendancePercentage>=0.56) (minorCollisionDays>=0 && minorCollisionDays<=90); (majorCollisionDays>=0 && majorCollisionDays<=90); violationAssessed==true; then qbr.setBonusAmount(0); end kbuilder has errors [9,21]: [ERR 102] Line 9:21 mismatched input '>=' in rule "1" [20,21]: [ERR 102] Line 20:21 mismatched input '>=' in rule "2" [0,0]: Parser returned a null Package ==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:1:2144330803:2144330803:1:DEFAULT:com.dfs.dsa.rules.QuarterlyBonusRules@7fcfe433], getObject()=com.dfs.dsa.rules.QuarterlyBonusRules@7fcfe433, getKnowledgeRuntime()=org.drools.impl.StatefulKnowledgeSessionImpl@23efdc4, getPropagationContext()=PropagationContextImpl [activeActivations=0, dormantActivations=0, entryPoint=EntryPoint::DEFAULT, factHandle=[fact 0:1:2144330803:2144330803:1:DEFAULT:com.dfs.dsa.rules.QuarterlyBonusRules@7fcfe433], leftTuple=null, originOffset=-1, propagationNumber=4, rule=null, type=0]] 11 Note: the number 11 is the value, it has printed, that I set to the bonus amount, but it should not print that value, it should pring 150. I am here attaching the spread sheet, where I have added all the rules in it. I appreciate you a lot for the help Thanks & Regards, Venkata. <http://drools.46999.n3.nabble.com/file/n4030519/quarterlyBonusRules.jpg> -- View this message in context: http://drools.46999.n3.nabble.com/I-am-getting-errors-for-Decision-Table-... Sent from the Drools: User forum mailing list archive at Nabble.com.