exception

Running hello rule:

rule "My First Drools Rule"
    when
        $o: Object()
    then
        System.out.println(" >>> Rule Fired for Object: "+$o.toString());
end

@Test
    public void hello() {
        Assert.assertNotNull(kSession);
        kSession.insert("Hi There From Test!");
        Assert.assertEquals(1, kSession.fireAllRules());
    }

java.lang.RuntimeException: Error while creating KieBase[Message [id=1, level=ERROR, path=rules.drl, line=22, column=0
   text=Unable to Analyse Expression isImported == true:
[Error: no such identifier: isImported]
[Near : {... isImported == true ....}]
             ^
[Line: 22, Column: 2]]]

Running tax rule:

rule "Applying taxes to imported products."
when

  // Take the order from working memory and get the product list from it
  $order: Order( $products: products != null )

  // Get only the imported products
  $product: Product( isImported == true ) from $products
then
  $product.setSale_tax($product.getPrize() * (5d/100));
  $order.setTotalPrize($product.getSale_tax() + $product.getPrize());
  $order.setTotalTaxes($product.getSale_tax());
  System.out.println($order.toString());
  System.out.println($order.getTotalPrize());
  System.out.println($order.getTotalTaxes());
end

@Test
    public void should_apply_rules_to_order2_exempetd_imported_not_imported() {
    	//GIVEN
    	Assert.assertNotNull(kSession);
    	final Order order2 = Utilities.createOrder2();
    	//WHEN
    	kSession.insert(order2);

    	//THEN
    	Assert.assertEquals(1, kSession.fireAllRules()); //failing
    	Assert.assertEquals("Shoud be equals...",65.15d, order2.getTotalPrize(),0d);
    	Assert.assertEquals("Shoud be equals...",7.65d, order2.getTotalTaxes(),0d);
    }

java.lang.AssertionError: expected:<1> but was:<0>