ADF BC: modifying VO bind params before executing the query

Question

Hi gang
I've a use case in ADF BC where I need to modify View Object bind parameters (eg. convert strings to uppercase) entered by users to change the result of the underlying VO query, and show the modified bind parameters to the user after the query.
Normally I would do this in the VO query by modifying the query where clause with the appropriate SQL. However this method is not applicable in this specific use case as the user doesn't get to see the modified bind parameters as a result.
I've thought about a few options including:
1) Generating the bind parameter accessors for the ViewObjectImpl and overriding the bind parameter setters to convert all string values to uppercase. This wasn't suitable as it looks like ADF Faces RC doesn't make use of the accessors via the default ADF bindings.
2) Overriding the applyViewCriteria() method in the ViewObjectImpl - which however isn't appropriate as it applies to search fields entered as view criteria, not bind parameters.
3) Overriding the executeQueryForCollection() method in the ViewObjectImpl - I thought I was on a winner here as I could retrieve the bind parameters via a call to getNamedWhereClauseParams(), modify the bind params and then call setNamedWhereClauseParams() to set them back. Unfortunately to really set the params I then need to call executeQuery() inside executeQueryForCollection() which puts the VO in a loop. You can see my sample code below:
@Override
protected void executeQueryForCollection(Object queryCollection,
                                         Object[] bindParams,
                                         int noUserParams) {
  AttributeList bindParamList = getNamedWhereClauseParams();
  String[] bindParamNames = bindParamList.getAttributeNames();
  Object[] bindParamValues = bindParamList.getAttributeValues();
  boolean valueChange = false;
  if (bindParamNames != null && bindParamValues != null) {
    String bindParamName = null;
    Object bindParamValue = null;
    for (int i = 0, j = bindParamNames.length; i < j; i++) {
      bindParamName = bindParamNames;
bindParamValue = bindParamValues[i];
if (bindParamName != null && !bindParamName.equals("")) {
if (bindParamValue instanceof String) {
if (bindParamValue != null && !bindParamValue.equals("")) {
bindParamList.setAttribute(bindParamName, (Object)((String)bindParamValue).toUpperCase());
valueChange = true;
} // else do nothing; null String
} // else do nothing; only interested in converting Strings to upper case
} // else do nothing; bind parameter name is null
} // else do nothing; bind parameter name or value list is null
if (valueChange) {
setNamedWhereClauseParams(bindParamList);
// executeQuery(); // we can't do this; causes an infinite loop
super.executeQueryForCollection(queryCollection, bindParams, noUserParams);
I can think of a number of solutions/hacks in ADF Faces RC to get around this issue, but ideally I'd like to keep the solution in the model layer. Does anybody have a better idea of how I could do this? Your help appreciated.
Thanks & regards,
CM.
PS. JDev 11g Boxer 5188: ADF BC + ADF Faces RC

Answer 1

Hi Chris,
have you tried modifying the passed-in bindParams argument to work around the need to call executeQuery()?
That's what I would've done:
I would have set the named where clause params (like you do) and after that I would have tried to get a new parameters Object[] back by calling ViewRowSetImpl.getParametersAsStorageType() and pass that to the super call.
Sascha