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Hibernate result list cast to get rows

Hello I had problem with iterate Hibernate ResultList
I had followed query that I got from external class:
queryContent = "select distinct c.identity, c.number, c.status, ctr.name, aab.paymentConditions.currency from AgreementStateBean ast join ast.currentAgreement aab join conagr.contract c where c.agreementStateId = ? and con.mainContractor = true ? "
And I must sum whole aab.paymentConditions.currency, check numbers of statutes and names.
I want to do this by iterate list of results:
Query q = session.createQuery(queryContent);
List result = q.list();
Long wholeCurrency, numberOfStatutes;
for(Object res : result){
//wholeCurrency += res.getColumnName?
}
My question is how to cast res Object to have possibility to get concrete column values? I had read about create map inside hibernate query but I don't know it is good practice to modyfied query string by adding
"new map(" prefix and then ")"
before from sql statement
Solution:
After All I decided to use map in my query. I modified my external query by adding hibernate map statement by replacing select by 'select new map(' and from by ') from'.
Additional thing is to add 'as' statement with name of key because without them column keys are integer.
So after all my query looks like follow:
"select new map( distinct c.identity, c.number, c.status as status, ctr.name as name, aab.paymentConditions.currency as currency ) from AgreementStateBean ast join ast.currentAgreement aab join conagr.contract c where c.agreementStateId = ? and con.mainContractor = true ? "
That was the most siutable solution for me, I tried with 'NEW com.example.MyClass' as Kostja suggested but in my case I didn't have control for incoming query so I can not rely on pernament constructor.
new List( select...
Is also interest but it also didn't tell me on with position I have my field that give me information.

If I understand correctly, you want to have a typed representation of your result without it being an entity itself. For this, you can use constructor queries:
"SELECT NEW com.example.MyClass( e.name, e.data) FROM Entity e"
MyClass has to have a matching constructor. Full qualification (com.example) is not mandatory AFAIK.
If you are using this query often, creating a view in the DB may be a good idea. You can map a view to an entity just as if it were a regular table, but please note that you cannot store changes to you data over a mapped view.
EDIT: Turns out, mapping to an unspecified Map is alright with Hibernate:
select new map( mother as mother, offspr as offspr, mate as mate )

As per http://docs.jboss.org/hibernate/orm/4.2/devguide/en-US/html/ch11.html#ql-select-clause
you can use
queryContent = "select new list(distinct c.identity, c.number, c.status, ctr.name, aab.paymentConditions.currency) from AgreementStateBean ast join ast.currentAgreement aab join conagr.contract c where c.agreementStateId = ? and con.mainContractor = true ? "
And you get List<List> as result.

Using sub queries

I am trying to access a data in a table using a sub query.
The table 1 contains a foreign key to table 2 , which means i can use that key to access the data in table 2.
My problem is after i return the array list from the below shown method , the arraylist is null.
This is what i have done:
LogEntry logBookDates;
List<LogEntry> bookList =new ArrayList();
try{
PreparedStatement getSummaryStmt=con.prepareStatement("SELECT * FROM LOGENTRYTABLE WHERE DIARYCODE =(SELECT Diarycode FROM LOGBOOKTABLE WHERE STUDENTUSERNAME=? OR SUPERVISORUSERNAME=? AND PROJECT_APPROVE_STATUS=?)");
//the above statment is the sub query which i have created, i get the diary code from log book table and then access the log entry table.
getSummaryStmt.setString(1,userName);
getSummaryStmt.setString(2,userName);
getSummaryStmt.setString(3,"Accepted");
ResultSet rs=getSummaryStmt.executeQuery();
while(rs.next())
{
logBookDates=new LogEntry(rs.getString("STUDENTUSERNAME"),rs.getString("SupervisorUsername"),rs.getString("projecttitle"),rs.getString("projectDescription"),rs.getDate("startDate"),rs.getDate("enddate"),rs.getString("project_approve_status"),rs.getString("diarycode"),rs.getString("projectcode"),rs.getInt("Index"),rs.getString("log_Entry"),rs.getDate("logentry_date"),rs.getString("supervisor_comment"),rs.getString("project_progress"));
bookList.add(logBookDates);
}
}catch(Exception e){}
return bookList;
}
I have not used sub queries before and this is the first time am using them.
What seems to be the problem here ?
Thank you for your time.
Edit : Sample data of logbook table
Sample Data of logentry table
Expected output:
I don't have a screen shot of that but what i need is just to iterate through the arraylist which will be returned from the above method.

Here is the problem, the LOGENTRYTABLE table doesn't contain a column with STUDENTUSERNAME, SupervisorUsername, projecttitle, projectDescription, startDate, etc...
rs.getString("STUDENTUSERNAME"), rs.getString("SupervisorUsername"), etc...
probably, you need JOIN query
"SELECT * FROM LOGENTRYTABLE LT
INNER JOIN LOGBOOKTABLE LB ON LT.DIARYCODE=LB.DIARYCODE
WHERE LT.DIARYCODE =
(SELECT DIARYCODE FROM LOGBOOKTABLE
WHERE (STUDENTUSERNAME=? OR SUPERVISORUSERNAME=?)
AND PROJECT_APPROVE_STATUS=?)"

Left_Join on same tables in Hibernate Criteria API

I have a table and a class marked as #Entity with
#Table(name="Employee")
It has two fields, Id and Name
i want to do left join on same table like,
Select t2.name, count(*)
from Employee t1 left join Employee t2 on t1.Id = t2.Id
where t1.Name = 'asd'
group by t2.Name

I had a workaround, I converted that query into sub query
Select EmployeeID From Employee
Where ManagerID in (Select EmployeeID where performance >= 4 )
And used DetachedCriteria and i got it worked. But this will reduce my performance. SO i will try your method and see if i can get it worked
Ref
https://forum.hibernate.org/viewtopic.php?p=2389790

How to flatten the results of a Hibernate query

Say I executed a theoretical HQL query like FROM Customer. And in Customer is a getOrders() getter returning a ManyToOne collection of Order objects. This executes a SQL statement selecting from Customer with a left join to Order.
Through the object model, I can programmaticly iterate over Customers and then iterate over Orders.
However, I want to convert the hierarchical object model to a flat tabular result of the left join so that the results would look much like that of this SQL query:
SELECT *
FROM Customer
LEFT JOIN Order on Customer.customerId = Order.customerId
Sample result:
Customer.customerId ... Order.orderId Order.customerId ...
1 200 1
2 201 2
2 202 2
3 NULL NULL
Is there an easy way to do this with Hibernate?

Depends what you want at the "scalar" level which you control through using an explicitl select clause.
select c, o
from Customer c left join c.orders o
returns you List of (Customer, Order) tuples. Or:
select c.id, c.name, o.id, ...
from Customer c left join c.orders o
which returns you a scalar projection of the atomic pieces.
In both cases you get back a List. You can use "dynamic instantiation" in both cases (though really its more useful in the second case imho):
select new CustomerOrderSummary( c.id, c.name, o.id, ... )
from Customer c left join c.orders o
where CustomerOrderSummary is just a plain class with matching constructor.

Possible you can do this via expressing of result set. http://docs.jboss.org/hibernate/orm/4.0/hem/en-US/html/query_native.html
From the example:
#SqlResultSetMapping(name="GetNightAndArea", entities={
#EntityResult(name="org.hibernate.test.annotations.query.Night", fields = {
#FieldResult(name="id", column="nid"),
#FieldResult(name="duration", column="night_duration"),
#FieldResult(name="date", column="night_date"),
#FieldResult(name="area", column="area_id")
}),
#EntityResult(name="org.hibernate.test.annotations.query.Area", fields = {
#FieldResult(name="id", column="aid"),
#FieldResult(name="name", column="name")
})
})

I think you can try retrieving results in Object[] e.g. below:
EntityManager entityManager = EntityManager.getEntityManager();
Query query= entityManager.createQuery("select cust, ord from Customer cust left outer join cust.orders ord where cust.customerId = :customerId");
tradeQuery.setParameter("customerId", aCustomerId);
List<Object[]> resultList = (List<Object[]>)query.getResultList();
The retrieved resultsList will be list of Object array containing Customer and Order objects in flat.
if(!resultList.isEmpty()){
Iterator<Object[]> iter = resultList.iterator();
while(iter.hasNext()){
Object[] resultObj = (Object[])iter.next();
Customer customer= (Customer )resultObj[0];
Order order = (Order)resultObj[1];
}
}
Hope this helps!

Select data from two tables using SQL

I have two tables linked by another table like this:
ROLES(RoleID, RoleName)
EMPLOYEES(EmployeeID, E_Name, Address)
ROLE_EMPLOYEES(RoleID#,EmployeeID#).
I want a query that retrieves all from EMPLOYEES and RoleID from ROLES and displays on Java form.
I have tried this but does not work:
rs=st.executeQuery("SELECT EMPLOYEES.*, ROLES.* FROM EMPLOYEES JOIN ROLES");
while(rs.next()){
//MOVE THE CURSOR TO THE FIRST RECORD AND GET DATA
int employeeid=rs.getInt("EmployeeID");
String id=Integer.toString(employeeid);
String name=rs.getString("E_Name");
String addr=rs.getString("Address");
String s = rs.getString("RoleID");
jComboBox1.addItem(s.trim());
//DISPLAY THE FIRST RECORD IN THE TEXT FIELD
txtEmpNumber.setText(id);
txtEmpName.setText(name);
txtEmpAddress.setText(addr);
jComboBox1.setSelectedItem(s);
}

You may try this:
SELECT
EM.*, RL.*
FROM
EMPLOYEES EM
INNER JOIN
ROLE_EMPLOYEES REM ON REM.EmployeeID = EM.EmployeeID
INNER JOIN
ROLES RL ON RL.RoleID = REM.RoleID
Just by writing the keyword JOIN the db-engine does not know in which way it should join the data of the tables; unless you want to retrieve a cartesian product (that's not your case), you need to explicitly set the criteria by using the ON clause.