@Test
 public void testApply_notUnique() {
   Generator<String> source = new SequenceTestGenerator<String>("A", "B");
   source.init(new DefaultBeneratorContext());
   Generator<String> generator = fcn.applyTo(source, false);
   generator.init(context);
   int n = 1000;
   Map<String, AtomicInteger> counts = super.countProducts(generator, n);
   assertEquals(2, counts.size());
   assertTrue(counts.get("A").doubleValue() > counts.get("B").doubleValue());
 }
 @Test(expected = IllegalArgumentException.class)
 public void testApply_unique() {
   Generator<String> source = new SequenceTestGenerator<String>("A", "B");
   source.init(new DefaultBeneratorContext());
   fcn.applyTo(source, true);
 }