jpa 2.0 - Is it possible to implement an exists query based on @ElementCollection using Jpa criteria query? -

i'm learning jpa criteria query , have no idea of how implement this:

i have entity called restaurant:

@entity @table(name = "t_f2g_restaurant",      uniqueconstraints = @uniqueconstraint(columnnames = { "name" })) public class restaurant {     @embeddedid     @attributeoverrides(         { @attributeoverride(name = "value", column = @column(name = "id")) })     private restaurantidentity id;      @column(name = "name")     private string name;      @elementcollection     @collectiontable(name = "t_f2g_restaurant_srv_area",          joincolumns = @joincolumn(name = "restaurant_id"))     @column(name = "zip_code")     private list<string> serviceareas = new arraylist<string>(); } 

now want count restaurants filtering serviceareas, below native sql implentation:

private boolean delegatetonativequery(address deliveryaddress {     string sqlstring = "select count(*) t_f2g_restaurant r "         + "where exists (select * t_f2g_restaurant_srv_area sa "         + "where sa.zip_code = ? , r.id = sa.restaurant_id) ";      query query = entitymanager.createnativequery(sqlstring);     query.setparameter(1, deliveryaddress.getzipcode());     return ((number) query.getsingleresult()).longvalue() > 0; } 

but how implement criteria query?

below attempt:

private boolean delegatetocriteriaquery(address deliveryaddress) {     criteriabuilder criteriabuilder = entitymanager.getcriteriabuilder();     criteriaquery<long> query = criteriabuilder.createquery(long.class);     root<restaurant> restaurant = query.from(restaurant.class);      subquery<long> serviceareasubquery = query.subquery(long.class);      /* causes t_f2g_restaurant, t_f2g_restaurant_srv_area join      root<restaurant> servicearearoot = serviceareasubquery         .from(restaurant.class);      listjoin<restaurant, string> serviceareas = servicearearoot         .joinlist("serviceareas");     serviceareasubquery.select(criteriabuilder.count(servicearearoot))         .where(criteriabuilder.             //servicearea represented string, what's attribute name?             equal(serviceareas.get("servicearea"), deliveryaddress.getzipcode()));      query.select(criteriabuilder.count(restaurant)).         where(criteriabuilder.exists(serviceareasubquery));      return entitymanager.createquery(query).getsingleresult() > 0; } 

i made now. hope answer helps someone.

criteriabuilder criteriabuilder = entitymanager.getcriteriabuilder(); criteriaquery<restaurant> query = criteriabuilder     .createquery(restaurant.class);  root<restaurant> restaurants = query.from(restaurant.class);  subquery<restaurant> serviceareasfiltering = query     .subquery(restaurant.class);  listjoin<object, object> serviceareas = serviceareasfiltering     .correlate(restaurants).joinlist("serviceareas"); //correlate joins t_f2g_restaurant , t_f2g_restaurant_srv_area  serviceareasfiltering.where(criteriabuilder.or(     criteriabuilder.equal(serviceareas, deliveryaddress.getstreet1()),     //equal against serviceareas use list<string> serviceareas     criteriabuilder.equal(serviceareas, deliveryaddress.getstreet2())));  query.where(criteriabuilder.exists(serviceareasfiltering));  return entitymanager.createquery(query).getresultlist(); 

frankly speaking, don't think criteria api easy read in case. won't switch criteria api unless need return list of restaurants(i need write result mapper if using native sql query).