Question

i have an app where i need to fire a jpql query with sum() and Func(year,…) functions, which means only 2 fields are to be fetched and stored into a collection and then this collection is to be returned to the managed bean. now my question is that how do i use this collection to retrieve each value. below is the session bean and managed bean code:

    public Collection getScripQtyYearWise(Integer scripID)
 {
    try
    {
     Collection coll=em.createQuery("select sum(t.tradeExecutedQuantity), FUNC('YEAR',t.tradeDateTime) from TradeStock t where t.scripID.scripID = :scripID group by FUNC('YEAR',t.tradeDateTime) ").setParameter("scripID", scripID).getResultList();
     return coll;
    }catch(Exception e){return null;}
 }

eg of data returned: sum(qty) year
210 2011
198 2012
i need to extract each of the values in each record returned in followinf managed bean:

  objejb=(StockCommodityEJBStateless) new InitialContext().lookup("StockCommodityTest");
 Collection coll=objejb.getScripQtyYearWise(scripID1); // how to use this collection?

Answer 1

coll is a Collection of Object[], so you can parse it like this:

    for (Object o : coll) {
        Object[] res = (Object[]) o;
        Object sum = res[0];
        Object year = res[1];

    }

If you want a List instead of Object[] you can change your select like this:

Collection coll=em.createQuery("select new list(sum(t.tradeExecutedQuantity), FUNC('YEAR',t.tradeDateTime)) from TradeStock t where t.scripID.scripID = :scripID group by FUNC('YEAR',t.tradeDateTime) ").setParameter("scripID", scripID).getResultList();

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