### Question:
JavaPeriodConverter implements Converter { @Override public Object toFacetValue(Object value) { if(value == null) { return null; } return Period.parse(value.toString()); }  @Override DataType getDataType(); @Override Class<?> getValueType(); @Override Object toColumnValue(Object value); @Override Object toFacetValue(Object value);  }### Answer:
@Test public void testToFacetValue() { Period oneMin = Period.ofYears(1); JavaPeriodConverter converter = new JavaPeriodConverter(); assertNull(converter.toFacetValue(null)); assertEquals(oneMin, converter.toFacetValue(oneMin.toString())); }