### Question:
DefaultNumberValue extends NumberValue { public static NumberValue of(Number number) { return new DefaultNumberValue(number); } DefaultNumberValue(Number number); static NumberValue of(Number number); @Override Class<?> getNumberType(); @Override int getPrecision(); @Override int getScale(); @Override int intValue(); @Override int intValueExact(); @Override long longValue(); @Override long longValueExact(); @Override float floatValue(); @Override double doubleValue(); @Override double doubleValueExact(); @Override long getAmountFractionNumerator(); @Override long getAmountFractionDenominator(); @Override T numberValue(Class<T> numberType); @Override NumberValue round(MathContext mathContext); @Override T numberValueExact(Class<T> numberType); @Override String toString(); static final NumberValue ONE; }### Answer:
@Test(expectedExceptions = NullPointerException.class) public void shouldReturnNPEWhenUseNullOnOfMethod() { DefaultNumberValue.of(null); }