### Question:
RealFunctionIntegrator1DFactory { public static Integrator1D<Double, Double> getIntegrator(String integratorName) { Integrator1D<Double, Double> integrator = STATIC_INSTANCES.get(integratorName); if (integrator != null) { return integrator; } throw new IllegalArgumentException("Integrator " + integratorName + " not handled"); } private  RealFunctionIntegrator1DFactory(); static Integrator1D<Double, Double> getIntegrator(String integratorName); static String getIntegratorName(Integrator1D<Double, Double> integrator); static final String ROMBERG; static final RombergIntegrator1D ROMBERG_INSTANCE; static final String SIMPSON; static final SimpsonIntegrator1D SIMPSON_INSTANCE; static final String EXTENDED_TRAPEZOID; static final ExtendedTrapezoidIntegrator1D EXTENDED_TRAPEZOID_INSTANCE; }### Answer:
@Test public void testBadName() { assertThatIllegalArgumentException() .isThrownBy(() -> RealFunctionIntegrator1DFactory.getIntegrator("a")); }