[rules-users] BRMS class cast exception

[Wojtek Kedzior]

Hello,

Im having trouble with the BRMS front end throwing an:

Exception in thread "main" java.lang.ClassCastException: java.util.HashSet cannot be cast to java.util.List
	at org.drools.rule.Package.readExternal(Package.java:172)


This is what I have set up:

  jbossweb-1.0.1.GA
  drools-4.0.1-brms
  Java version 1.6.0 - VM 1.6.0-b105

mvel jar file:

  mvel14-1.2rc4rv908 (taken from the jbossweb lib)


This is the class, which i put into a .jar, which in turn I import into the front end:


package data;

import java.io.Serializable;

public class ExceptionType implements Serializable{
	private String customerType = "";
	private String exceptionType = "";
	
	public ExceptionType(){}
	
	public ExceptionType(String customerType, String exceptionType)
	{
		this.exceptionType = exceptionType;
		this.customerType = customerType;
	}
	
	public void setExceptionType(String exceptionType) {
		this.exceptionType = exceptionType;
	}
	
	public String getExceptionType() {
		return exceptionType;
	}
	
	public void setCustomerType(String customerType) {
		this.customerType = customerType;
	}
	
	public String getCustomerType() {
		return customerType;
	}
}




And here is the starting point:




package data;

import java.util.Properties;

import org.drools.RuleBase;
import data.ExceptionType;
import org.drools.StatefulSession;
import org.drools.agent.RuleAgent;


public class Runner {
	public Runner()
	{
		ExceptionType e = new ExceptionType("das", "32432");
		e.setExceptionType("system failure");
		
		Properties prop = new Properties();
		prop.setProperty("newInstance", "true");
		prop.setProperty("url","http://localhost:8080/drools-jbrms/org.drools.brms.JBRMS/package/defaultPackage/snap2");	
		prop.setProperty("poll", "30");
	
		RuleAgent agent = RuleAgent.newRuleAgent(prop);  //error occurs on this line.
		RuleBase rb = agent.getRuleBase();
		
		StatefulSession session = rb.newStatefulSession();
		session.insert(e);
		session.fireAllRules();	
	}
	/**
	 * @param args
	 */
	public static void main(String[] args)
	{
		new Runner();
	}
}


I have specified a package import in the packge in the front end:

   import data.ExceptionType

Validation of the .jar file and build of the package seem to work fine.



Here is the complete stack trace:

RuleAgent(default) INFO (Fri Sep 28 21:57:54 NZST 2007): Configuring with newInstance=true, secondsToRefresh=30
RuleAgent(default) INFO (Fri Sep 28 21:57:54 NZST 2007): Configuring package provider : URLScanner monitoring URLs:  http://localhost:8080/drools-jbrms/org.drools.brms.JBRMS/package/defaultPackage/snap2
Exception in thread "main" java.lang.ClassCastException: java.util.HashSet cannot be cast to java.util.List
	at org.drools.rule.Package.readExternal(Package.java:172)
	at java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1792)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1751)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
	at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351)
	at org.drools.agent.HttpClientImpl.fetchPackage(HttpClientImpl.java:54)
	at org.drools.agent.URLScanner.readPackage(URLScanner.java:137)
	at org.drools.agent.URLScanner.getChangeSet(URLScanner.java:109)
	at org.drools.agent.URLScanner.loadPackageChanges(URLScanner.java:88)
	at org.drools.agent.RuleAgent.checkForChanges(RuleAgent.java:297)
	at org.drools.agent.RuleAgent.refreshRuleBase(RuleAgent.java:265)
	at org.drools.agent.RuleAgent.configure(RuleAgent.java:251)
	at org.drools.agent.RuleAgent.init(RuleAgent.java:183)
	at org.drools.agent.RuleAgent.newRuleAgent(RuleAgent.java:140)
	at data.Runner.<init>(Runner.java:25)
	at data.Runner.main(Runner.java:37)


Any help would be appreciated.


Thanks,

Wojtek Kedzior

First Data Utilities
Auckland, New Zealand

Software Engineering