### Question:
PrimitiveUtils { public static boolean isPrimitiveWrapper(Class<?> type) { return wrapperTypes.containsKey(type); } private  PrimitiveUtils(); static Object getEmptyValue(Class<?> type); static Class<?> getWrapperType(Class<?> type); static boolean isPrimitiveWrapper(Class<?> type); static String getPrimitiveTypeNameFromWrapper(Class<?> type);  }### Answer:
@Test public void isNumberWrapper() { assertTrue(PrimitiveUtils.isPrimitiveWrapper(Byte.class)); assertTrue(PrimitiveUtils.isPrimitiveWrapper(Short.class)); assertTrue(PrimitiveUtils.isPrimitiveWrapper(Integer.class)); assertTrue(PrimitiveUtils.isPrimitiveWrapper(Long.class)); assertTrue(PrimitiveUtils.isPrimitiveWrapper(Float.class)); assertTrue(PrimitiveUtils.isPrimitiveWrapper(Double.class)); assertFalse(PrimitiveUtils.isPrimitiveWrapper(getClass())); assertFalse(PrimitiveUtils.isPrimitiveWrapper(Integer.TYPE)); }