java - Filling dropdown list with related tables name in JSP -

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i have following structure of database created in hibernate4:

department (has fields: department_id , department_name) connected through department_institute (has department_id , institute_id) institute (has institute_id , institute_name) later connected through institute_teacher (by id's again) teacher (teacher_id, name, surname, title).

it has 1 many relationship 1 department can have many institutes , 1 institute can have many teachers.

i put object , through jstl put 1 dropdown menu (dropdown list doesn't need have few levels, can on same level). problem is, don't know:

  • how query data , put them 1 list,

  • use jstl in jsp put them in dropdown menu.

    could tell me how that? love understand that. here skeleton of method querying "everything":

[edit] here made method querying database, if have if it's solution or not, grateful

    public list<string> enlisteverything(){     session session = sessionfactory.opensession();     transaction tx = null;     list<string> toview = new arraylist<string>();     try{         tx = session.begintransaction();         hashset<department> departments = (hashset<department>)session.createquery("from department").list();         hashset<institute> institutes = new hashset<institute>();         hashset<teacher> teachers = new hashset<teacher>();          for(department d : departments){             toview.add(d.getdepartmentname());             institutes.addall(d.getinstitutes());          }         for(institute : institutes){             toview.add(i.getinstitutename());             teachers.addall(i.getteachers());     }     for(teacher t : teachers){             toview.add(t.getteachertitle() + t.getteachername() + t.getteachersurname());         }     }catch(hibernateexception e){         if (tx!=null) tx.rollback();         e.printstacktrace();     } {         session.close();     }     return toview;     }

i've done datamodel using particular tutorial: http://www.dzone.com/tutorials/java/hibernate/hibernate-example/hibernate-mapping-one-to-many-1.html inside department class there hashset institutes , in institutes there hashset teachers. thank in advance answers.

i put object , through jstl put 1 dropdown menu (dropdown list doesn't need have few levels, can on same level).

use toview map instead of list keep key-value pairs put dropdown menu.

map<string,string> toview = new linkedhashmap<string,string>(); .. .. toview.put(d.getdepartmentid()+"dept",d.getdepartmentname()); toview.put(i.getinstituteid()+"inst",i.getinstitutename()); toview.put(t.getteacherid()+"teach",t.getteachertitle() + t.getteachername() + t.getteachersurname());

add map request:

map<string, string> toview = yourdataprovider.enlisteverything(); request.setattribute("toview", toview);

now in jsp, use put values in dropdown menu:

<select name="mapdata">     <c:foreach items="${toview}" var="data">         <option value="${data.key}">${data.value}</option>     </c:foreach> </select>

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