### Question:
RandomWalkEQOracle implements MealyEquivalenceOracle<I, O> { @Override public @Nullable DefaultQuery<I, Word<O>> findCounterExample(MealyMachine<?, I, ?, O> hypothesis, Collection<? extends I> inputs) { return doFindCounterExample(hypothesis, inputs); } RandomWalkEQOracle(SUL<I, O> sul,
                              double restartProbability,
                              long maxSteps,
                              boolean resetStepCount,
                              Random random);  RandomWalkEQOracle(SUL<I, O> sul, double restartProbability, long maxSteps, Random random); @Override @Nullable DefaultQuery<I, Word<O>> findCounterExample(MealyMachine<?, I, ?, O> hypothesis,
                                                                 Collection<? extends I> inputs);  }### Answer:
@Test public void testOracle() { final DummySUL dummySUL = new DummySUL(); final MealyEquivalenceOracle<Character, Character> mOracle = new RandomWalkEQOracle<>(dummySUL, 0.01, MAX_LENGTH, new Random(42)); final DefaultQuery<Character, Word<Character>> ce = mOracle.findCounterExample(new DummyMealy(ALPHABET), ALPHABET); Assert.assertNull(ce); Assert.assertTrue(dummySUL.isCalledPost()); }