How to Access Columns generated by projection criteria in Hibernate(pseudo columns)?

Question

This is criteria which returns 6 columns.
ProjectionList projList = Projections.projectionList();

    projList.add(Projections.property("se.ticker"),"ticker");
    projList.add(Projections.property("cl.firstName"),"firstName");
    projList.add(Projections.property("cl.middleName"),"middleName");
    projList.add(Projections.property("tr.client"),"client");
    projList.add(Projections.sum("tr.cumulativeQty"),"cumulativeQty");
    projList.add(Projections.sum("tr.cumulativeBalance"),"cumulativeBalance");
    projList.add(Projections.groupProperty("tr.securityId"));

    Criteria criteria = createEntityCriteria(TransactionDetails.class, "tr")
            .createAlias("tr.client", "cl")
            .createAlias("tr.security", "se")
            .add(Restrictions.eq("cl.id", clientId))
            .setProjection(projList);




    return (List<TransactionDetails>) criteria.list();

How to access column details(data with column). I have given the alias name but its of no use. Please Suggest me the way to access the column data.

score 0 · Answer 1 · edited May 23 '17 at 12:05

You have two options

1 > You will get result as a list of array. you can iterate though them and get the columns.

List<Object[]> criteria = criteria.list();

for (Object[] result : results) {
    String ticker = (String)result[0];
    String firstName = (String)result[1];
    // other properties same way

}

2 > You can specify result transformer, hibernate will do the rest. You have to map columns in the projections with the VO object columns.

In you case you can have a VO object as below.

class TransactionDetailVO{
    String ticker;
    String firstName;
    String lastName;
    //other properties. these properties map to the alias in projection      projList.add(Projections.property("cl.firstName"),"firstName"). here it is `firstName`.
}


Criteria criteria = createEntityCriteria(TransactionDetails.class, "tr")
            .createAlias("tr.client", "cl")
            .createAlias("tr.security", "se")
            .add(Restrictions.eq("cl.id", clientId))
            .setProjection(projList)
            .setResultTransformer(Transformers.aliasToBean(TransactionDetailVO.class));


List criteria = criteria.list();

for (Object result : results) {
    TransactionDetailVO transactionDetailVO = (TransactionDetailVO)result;
    // access the properties.
}

Here is an example.

score 0 · Accepted Answer · edited Jun 20 '20 at 09:12

I used Iterator to get the data. Its working now.

transactionDetailsList = transactionDetailsDao.getClientHoldingsBySecurityIdClientId(securityId, clientId);

        List list = transactionDetailsList;
        Iterator it = list.iterator();
        if (!it.hasNext()) {
            System.out.println("No any data!");
        } else {
            while (it.hasNext()) {
                TransactionDetailsDto transactionDetailsDto = new TransactionDetailsDto();
                Object[] row = (Object[]) it.next();
                int count=0;
                for (int i = 0; i < row.length; i++) {

                    switch (i) {
                        case 0:
                            transactionDetailsDto.setClientMasterId(Long.valueOf(row[i].toString()));
                            Client client = clientDAO.load(transactionDetailsDto.getClientMasterId());
                            transactionDetailsDto.setClientDto(new ClientTransformer().transform(client));
                            break;
                                }
                      }

}

How to Access Columns generated by projection criteria in Hibernate(pseudo columns)?

2 Answers2