I have what looks to me like a Drools bug on a simple drl with declared classes. I'm using version drools-distribution-5.3.0.Final.

I'm invoking it with this:

StatelessKnowledgeSession ksession = kbase.newStatelessKnowledgeSession();

List<Object> facts = new ArrayList<Object>();

ksession.execute( facts );

=============================

I get this crash:

Exception in thread "main" java.lang.NoClassDefFoundError: com/sample/Cap

at ASMAccessorImpl_129541121334339192620.getValue(Unknown Source)

at org.mvel2.optimizers.dynamic.DynamicGetAccessor.getValue(DynamicGetAccessor.java:73)

at org.mvel2.ast.ASTNode.getReducedValueAccelerated(ASTNode.java:103)

at org.mvel2.compiler.ExecutableAccessor.getValue(ExecutableAccessor.java:42)

at org.mvel2.MVEL.executeExpression(MVEL.java:952)

...

==========================

Here's the drl file:

package com.sample

import com.sample.*;

declare Item

id : int;

end

declare Priority

name : String;

priority : int;

end

declare Cap

item : Item;

name : String

end

rule "split cart into items"

when

then

insert(new Item(1));

insert(new Item(2));

insert(new Item(3));

end

rule "Priorities"

when

then

insert(new Priority("A", 3));

insert(new Priority("B", 2));

insert(new Priority("C", 5));

end

rule "Caps"

when

$i : Item()

$p : Priority($name : name)

then

insert(new Cap($i, $name));

end

rule "test"

when

$i : Item()

Cap(item.id == $i.id)

then

System.out.println("Cap");

end

====================

Some observations:

- If I comment out any of the insert lines, the crash goes away

- If I change the first field of class Cap to be id:int instead of item:Item and make the corresponding changes, the crash goes away