//i.e. ${payload:org.mule.tck.testmodels.fruit.FruitBasket}
Object result = muleContext.getExpressionManager().evaluate("#[mule:message.payload(org.mule.tck.testmodels.fruit.FruitBasket)]", message);
assertNotNull(result);
assertTrue(result instanceof FruitBasket);
FruitBasket fb = (FruitBasket) result;
assertEquals(2, fb.getFruit().size());
assertTrue(fb.hasBanana());
assertTrue(fb.hasApple());
}