### Question:
DateConverter implements AttributeConverter<Date,String> { @Override public String convertToDatabaseColumn(Date attribute) { if(attribute==null) { return null; } return Long.toString(attribute.getTime()); }  @Override String convertToDatabaseColumn(Date attribute); @Override Date convertToEntityAttribute(String dbData);  }### Answer:
@Test public void testConvertToDatabaseColumn() throws Exception { DateConverter sut=new DateConverter(); assertThat(sut.convertToDatabaseColumn(null),nullValue()); }