What type is returned form HQL query using count(*).

This worked in Hibernate 2 versions and I've recently upgraded to 3 and noticed this no longer works.

When using a query that is using the syntax

select new com.foo.Bah(f.name, count(*))
from Foo
Where condition = condition
grouby something

Bah old working constructors don't seem to be recognised anymore which makes me think the type returned from count(*) has changed? if I removed the count(*) from the query, the Bah(string) constructor is found no problem.

Bah(String, int); // doesn't work
Bah(String, Integer); //doesn't work



Hibernate version: Hibernate-Version: 3.2.0.ga

Mapping documents: Snippet


<query name="getStats">

Select new new com.somecompany.db.model.TestStats(testcaseresult.className, count(*), sum(testcaseresult.runTime), testcaseresult.result)
from TestCaseResult as testcaseresult
where testcaseresult.testSuiteRunId = :testSuiteRunId
group by testcaseresult.className, testcaseresult.result
</query>


Full stack trace of any exception that occurs:

Nov 20, 2006 6:16:04 PM org.hibernate.hql.ast.ErrorCounter reportError
SEVERE: Unable to locate appropriate constructor on class [com.bea.test.results.db.model.TestCaseResultsClassStats]
[cause=org.hibernate.PropertyNotFoundException: no appropriate constructor in class: com.bea.test.results.db.model.TestCaseResultsClassStats]
Nov 20, 2006 6:16:04 PM org.hibernate.hql.ast.ErrorCounter reportError
SEVERE: Unable to locate appropriate constructor on class [com.bea.test.results.db.model.TestCaseResultsClassStats]
[cause=org.hibernate.PropertyNotFoundException: no appropriate constructor in class: com.bea.test.results.db.model.TestCaseResultsClassStats]
Nov 20, 2006 6:16:04 PM org.hibernate.impl.SessionFactoryImpl <init>
SEVERE: Error in named query: getTestCaseResultsClassStats
org.hibernate.hql.ast.QuerySyntaxException: Unable to locate appropriate constructor on class [com.bea.test.results.db.model.TestCaseResultsClassStats] [
select new com.bea.test.results.db.model.TestCaseResultsClassStats(testcaseresult.className, count(*), sum(testcaseresult.runTime), testcaseresult.result)
from com.bea.test.results.db.model.TestCaseResult as testcaseresult
where testcaseresult.testSuiteRunId = :testSuiteRunId
group by testcaseresult.className, testcaseresult.result
]
at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:31)
at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:24)
at org.hibernate.hql.ast.ErrorCounter.throwQueryException(ErrorCounter.java:59)
at org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:235)
at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:160)
at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:111)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:77)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:56)
at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:72)
at org.hibernate.impl.SessionFactoryImpl.checkNamedQueries(SessionFactoryImpl.java:400)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:351)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1218)
at com.bea.test.results.db.hibernate.SessionFactory.currentSession(SessionFactory.java:49)
at com.bea.test.results.db.TestClient.doStuff(TestClient.java:29)
at com.bea.test.results.db.TestClient.main(TestClient.java:74)
Nov 20, 2006 6:16:04 PM org.hibernate.impl.SessionFactoryImpl <init>
SEVERE: Error in named query: getTestClassResultStats
org.hibernate.hql.ast.QuerySyntaxException: Unable to locate appropriate constructor on class [com.bea.test.results.db.model.TestCaseResultsClassStats] [
select new com.bea.test.results.db.model.TestCaseResultsClassStats(testcaseresult.className, count(*), sum(testcaseresult.runTime), testcaseresult.result)
from com.bea.test.results.db.model.TestCaseResult as testcaseresult
where testcaseresult.className = :className
and testcaseresult.testSuiteRunId = :testSuiteRunId
group by testcaseresult.className, testcaseresult.result
]
at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:31)
at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:24)
at org.hibernate.hql.ast.ErrorCounter.throwQueryException(ErrorCounter.java:59)
at org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:235)
at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:160)
at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:111)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:77)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:56)
at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:72)
at org.hibernate.impl.SessionFactoryImpl.checkNamedQueries(SessionFactoryImpl.java:400)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:351)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1218)
at com.bea.test.results.db.hibernate.SessionFactory.currentSession(SessionFactory.java:49)
at com.bea.test.results.db.TestClient.doStuff(TestClient.java:29)
at com.bea.test.results.db.TestClient.main(TestClient.java:74)
%%%% Error Creating SessionFactory %%%%
org.hibernate.HibernateException: Errors in named queries: getTestCaseResultsClassStats, getTestClassResultStats
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:364)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1218)
at com.bea.test.results.db.hibernate.SessionFactory.currentSession(SessionFactory.java:49)
at com.bea.test.results.db.TestClient.doStuff(TestClient.java:29)
at com.bea.test.results.db.TestClient.main(TestClient.java:74)
Exception in thread "main" java.lang.NullPointerException
at com.bea.test.results.db.TestClient.doStuff(TestClient.java:30)
at com.bea.test.results.db.TestClient.main(TestClient.java:74)


Name and version of the database you are using: MySql 5

Did you enable the debug level to see if Query parser outputs any more information.
Another way is to make the constructor something like
public Bah (String, Object)
and try and print out the actual Object that it returns.

According to the Hibernate migration guide for 3.2 (http://www.hibernate.org/250.html), count(*) now returns long.

Curtis ...

this was a fantastic solution, thnx for this solution, it worked, i changed my type from short to long and it worked for me !!!!!

one more question, is it compulsory to use pojo class in hibernate query?

eg- my query is :
select new UpdateCountDataBean(count(actionId), pname) from ActivityMaster group by pname

where UpdateCountDataBean is not a POJO. instead if i use a pojo class named "UpdateCount", it works, so is it like tht we have to use pojo compulsorily?