/**
* Selects exactly one LOB (of the target type) from exactly one query row.
*
* @param pUCon
* @return True if a valid row was selected, false otherwise.
* @throws ExDBTimeout
*/
protected boolean selectRow(UCon pUCon) throws ExDBTimeout {
ExecutableQuery lSelectQuery = mWorkingStorageLocation.getExecutableSelectStatement();
try {
SingleRowResultDeliverer lDeliverer = new SingleRowResultDeliverer();
lSelectQuery.executeAndDeliver(pUCon, lDeliverer);
Map<String, Object> lColumnMap = lDeliverer.getColumnMap();
LOBAccessor<T> lLOBAccessor = null;
int lLOBsFound = 0;
COL_LOOP:
for (Map.Entry<String, Object> lColumn : lColumnMap.entrySet()) {
Object lColObject = lColumn.getValue();
// If we don't know what LOB type we're looking for, try and get an accessor for every
// object, otherwise only
// attempt to get an accessor for columns of the desired type.
if (lColObject != null
&& (mLOBClass == AnyLOBType.class || mLOBClass.isInstance(lColObject))) {
LOBAccessor<T> lLOBAccessorOrNull =
LOBAccessor.getAccessorForLOBOrNull(lColObject, mLOBClass);
if (lLOBAccessorOrNull != null) {
lLOBsFound++;
lLOBAccessor = lLOBAccessorOrNull;
}
}
}
// Looped all columns without finding exactly one compatible LOB - this is an error
if (lLOBsFound != 1) {
throw new ExInternal(
"Select query for "
+ mWorkingStorageLocation.getStorageLocationName()
+ " failed to locate exactly one non-null "
+ mLOBClass.getSimpleName()
+ " column (got "
+ lLOBsFound
+ ")");
} else {
mLOBAccessor = lLOBAccessor;
}
return true;
} catch (ExDBTooFew e) {
return false;
} catch (ExDBTooMany e) {
throw new ExInternal(
"Select query for "
+ mWorkingStorageLocation.getStorageLocationName()
+ " returned more than 1 row",
e);
} catch (ExDBTimeout e) {
throw e;
} catch (ExDB e) {
throw new ExInternal(
"Error running select query for " + mWorkingStorageLocation.getStorageLocationName(), e);
}
}
/**
* Constructs a new UConStatementResult from a ResultSet.
*
* @param pResultSet
* @return New UConStatementResult.
* @throws SQLException If ResultSet read fails.
*/
static UConStatementResult fromResultSet(ResultSet pResultSet) throws SQLException {
return new UConStatementResult(
SingleRowResultDeliverer.createObjectMapFromResultSet(pResultSet));
}