I'm trying to persists JodaTime DateTime fields with JPA to PostgreSQL but run into troubles with null pointers to database NULL values.
I'm working with the NetBeans 7 beta 2 IDE. The persistence implementation is EclipseLink 2.2.0 and I'm using an EclipseLink Converter to get the mapping to work. Here is the declaration of my field:
@Converter(
name="dateTimeConverter",
converterClass=ejb.util.DateTimeConverter.class
)
@Column(columnDefinition="TIMESTAMP WITH TIME ZONE")
@Convert("dateTimeConverter")
private DateTime testdate;
The converter class:
public class DateTimeConverter implements Converter {
private Logger log;
private static final long serialVersionUID = 1L;
@Override
public Object convertObjectValueToDataValue(Object o, Session sn) {
if (o == null) {
log.info("convertObjectValueToDataValue returning null");
return null;
}
return ((DateTime)o).toDate();
}
@Override
public Object convertDataValueToObjectValue(Object o, Session sn) {
if (o == null) {
log.info("convertDataValueToObjectValue returning null");
return null;
}
return new DateTime(o);
}
@Override
public boolean isMutable() {
return true;
}
@Override
public void initialize(DatabaseMapping dm, Session sn) {
log = Logger.getLogger("ejb.util.DateTimeConverter");
}
}
This works fine as long as there is an actual DateTime set. But as soon as it is not set EclipseLink seems to assume a string type and postgresql starts complaining about the value being of the type character varying. I assume this is because the converter class is returning a null pointer instead of a date object and EclipseLink falls back on a default.
Is there a way to get this to work short of switching to plain java.util.Date?
When a @Converter
is used, EclipseLink does not know the type, so you need to initialize it.
In your initialize(DatabaseMapping dm, Session sn)
method you need to set the type,
dm.setFieldClassification(java.sql.Date.class);
// or, dm.setFieldClassification(java.sql.Timestamp.class);