### Question:
TransactionPurchasesHiddenMarkovModel implements ConditionalSampler<List<Product>, Double> { protected Product chooseProduct(String category) throws Exception { return this.purchasingProcesses.sample(category); } TransactionPurchasesHiddenMarkovModel(ConditionalSampler<Product, String> purchasingProcesses,
			ConditionalWeightFunction<Double, Double> categoryWF, CustomerInventory inventory,
				SeedFactory seedFactory); List<Product> sample(Double transactionTime);  }### Answer:
@Test public void testChooseProduct() throws Exception { TransactionPurchasesHiddenMarkovModel hmm = createHMM(); Product product = hmm.chooseProduct("dog food"); assertNotNull(product); assertTrue(product.getFieldValue(Constants.PRODUCT_CATEGORY).equals("dog food")); product = hmm.chooseProduct("cat food"); assertNotNull(product); assertTrue(product.getFieldValue(Constants.PRODUCT_CATEGORY).equals("cat food")); }