### Question:
Benchmark { public Set<String> header(int runs, boolean includeErrors) { Benchmark result = new Benchmark(); Engine dummy = new Engine(); dummy.addOutputVariable(new OutputVariable()); result.setEngine(dummy); Double[] dummyTimes = new Double[runs]; Arrays.fill(dummyTimes, Double.NaN); result.setTimes(Arrays.asList(dummyTimes)); if (includeErrors) { double[] dummyArray = new double[1]; List<double[]> dummyList = new ArrayList<double[]>(); dummyList.add(dummyArray); result.setExpected(dummyList); result.setObtained(dummyList); } return result.results().keySet(); } Benchmark();  Benchmark(String name);  Benchmark(String name, Engine engine);  Benchmark(String name, Engine engine, double tolerance); String getName(); void setName(String name); Engine getEngine(); void setEngine(Engine engine); List<double[]> getExpected(); void setExpected(List<double[]> expected); List<double[]> getObtained(); void setObtained(List<double[]> obtained); List<Double> getTimes(); void setTimes(List<Double> times); double getTolerance(); void setTolerance(double tolerance); void prepare(int values, FldExporter.ScopeOfValues scope); void prepare(Reader reader); void prepare(Reader reader, long numberOfLines); double runOnce(); double[] run(int times); void reset(); boolean canComputeErrors(); double meanSquaredError(); double meanSquaredError(OutputVariable outputVariable); int allErrors(); int allErrors(OutputVariable outputVariable); int nonFiniteErrors(); int nonFiniteErrors(OutputVariable outputVariable); int accuracyErrors(); int accuracyErrors(OutputVariable outputVariable); int numberOfErrors(ErrorType errorType); int numberOfErrors(ErrorType errorType, OutputVariable outputVariable); double factorOf(TimeUnit unit); double convert(double time, TimeUnit from, TimeUnit to); Set<String> header(int runs, boolean includeErrors); Map<String, String> results(); Map<String, String> results(TimeUnit timeUnit); Map<String, String> results(TimeUnit timeUnit, boolean includeTimes); Map<String, String> results(OutputVariable outputVariable); Map<String, String> results(OutputVariable outputVariable, TimeUnit timeUnit); Map<String, String> results(OutputVariable outputVariable, TimeUnit timeUnit, boolean includeTimes); String format(Map<String, String> results); String format(Map<String, String> results, TableShape shape); String format(Map<String, String> results, TableShape shape,
            TableContents contents); String format(Map<String, String> results, TableShape shape,
            TableContents contents, String delimiter);  }### Answer:
@Test public void testHeaders() { Benchmark benchmark = new Benchmark(); Assert.assertThat(benchmark.header(10, true).size(), is(30)); Assert.assertThat(benchmark.header(10, false).size(), is(30 - 8)); }