/** INTERNAL: Select one object of any concrete subclass. */
protected Object selectOneObject(ReadObjectQuery query) throws DescriptorException {
ReadObjectQuery concreteQuery = (ReadObjectQuery) query.clone();
Class javaClass = descriptor.getJavaClass();
concreteQuery.setReferenceClass(javaClass);
concreteQuery.setDescriptor(descriptor);
return query.getSession().executeQuery(concreteQuery, concreteQuery.getTranslationRow());
}
/**
* INTERNAL: Return the value of the field from the row or a value holder on the query to obtain
* the object. Check for batch + aggregation reading.
*/
@Override
public Object valueFromRow(
AbstractRecord row,
JoinedAttributeManager joinManager,
ObjectBuildingQuery sourceQuery,
AbstractSession executionSession)
throws DatabaseException {
// If any field in the foreign key is null then it means there are no referenced objects
for (Enumeration enumeration = getFields().elements(); enumeration.hasMoreElements(); ) {
DatabaseField field = (DatabaseField) enumeration.nextElement();
if (row.get(field) == null) {
return getIndirectionPolicy().nullValueFromRow();
}
}
if (getTypeField() != null) {
// If the query used batched reading, return a special value holder,
// or retrieve the object from the query property.
if (sourceQuery.isReadAllQuery()
&& (((ReadAllQuery) sourceQuery).isAttributeBatchRead(getDescriptor(), getAttributeName())
|| shouldUseBatchReading())) {
return batchedValueFromRow(row, ((ReadAllQuery) sourceQuery));
}
// If the field is empty we cannot load the object because we do not know what class it will
// be
if (row.get(getTypeField()) == null) {
return getIndirectionPolicy().nullValueFromRow();
}
Class implementerClass =
(Class) getImplementorForType(row.get(getTypeField()), executionSession);
ReadObjectQuery query = (ReadObjectQuery) getSelectionQuery().clone();
query.setReferenceClass(implementerClass);
query.setSelectionCriteria(getSelectionCriteria());
query.setDescriptor(null); // Must set to null so the right descriptor is used
if (sourceQuery.isObjectLevelReadQuery()
&& (sourceQuery.shouldCascadeAllParts()
|| (sourceQuery.shouldCascadePrivateParts() && isPrivateOwned())
|| (sourceQuery.shouldCascadeByMapping() && this.cascadeRefresh))) {
query.setShouldRefreshIdentityMapResult(sourceQuery.shouldRefreshIdentityMapResult());
query.setCascadePolicy(sourceQuery.getCascadePolicy());
query.setShouldMaintainCache(sourceQuery.shouldMaintainCache());
// For flashback.
if (((ObjectLevelReadQuery) sourceQuery).hasAsOfClause()) {
query.setAsOfClause(((ObjectLevelReadQuery) sourceQuery).getAsOfClause());
}
// CR #4365 - used to prevent infinit recursion on refresh object cascade all
query.setQueryId(sourceQuery.getQueryId());
}
return getIndirectionPolicy().valueFromQuery(query, row, executionSession);
} else {
return super.valueFromRow(row, joinManager, sourceQuery, executionSession);
}
}