I'm using Drools 5.4.0 Beta 1 and my DRL is the Hello World of Drools :) (all my application is the Hello World of Drools, because I'm trying to do a OSGi bundle with this application).

In my OSGi framework is running drools.core, drools.compiler and knowledge-api, and others bundles. 

Thanks for reply me.

On Tue, Jan 10, 2012 at 6:15 PM, Swindells, Thomas <TSwindells@nds.com> wrote:
Looking at the stack trace, if you are on the same version as drools as me it looks like it is this line
this.rule.setDialect( getDialect().getId() );

The most likely reason is your DRL isn't valid - perhaps where you are specifying the dialect, or it could be your
Dependencies aren't right or something.
Which version of drools are you using. Have you tried reducing your DRL file to the minimum that generates the error - then post that DRL if you need further help.

Thomas

> -----Original Message-----
> From: rules-users-bounces@lists.jboss.org [mailto:rules-users-
> bounces@lists.jboss.org] On Behalf Of jjmartinez
> Sent: 10 January 2012 17:05
> To: rules-users@lists.jboss.org
> Subject: Re: [rules-users] NullPointerException when load file rules
>
> Anybody can help me? I don't know why my application show these errors.
>
> Thanks in advance!
>
> java.lang.NullPointerException
       at org.drools.rule.builder.RuleBuildContext.<init>(RuleBuildContext.java:88)
       at org.drools.compiler.PackageBuilder.addRule(PackageBuilder.java:1149)
       at org.drools.compiler.PackageBuilder.addPackage(PackageBuilder.java:636)
       at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:266)
       at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:458)
       at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28)
       at drools.ejemplos.DroolsTest.readKnowledgeBase(DroolsTest.java:85)
       at drools.ejemplos.DroolsTest.execute(DroolsTest.java:64)
       at drools.ejemplos.DroolsTest.<init>(DroolsTest.java:56)
       at drools.ejemplos.Activator.start(Activator.java:14)
       at org.knopflerfish.framework.BundleImpl.start0(BundleImpl.java:356)
       at org.knopflerfish.framework.BundleThread.run(BundleThread.java:107)


**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster@nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary.

NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00
**************************************************************************************

_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users