Java SQL Server Application Stuck On statement.executeUpdate() -

i have rather annoying issue. in piece of code below, trying insert new row "revisiondispersion" table in database. however, whenever call stmt.executeupdate() program freezes , there ends being no transaction database. no matter how long wait; database won't updated. below code of interest:

private static final string insert_dispersion = "insert revisiondispersion("                                                + assignments.id + ", "                                                + persons.email + ", "                                                + handins.id + ")"                                                + " values(?, ?, ?)";  public static void disperse(datasource source, assignment assignment) throws exception {     list<string> handins = assignment.gethandins();      //used decide checks assignment     int maxrng = math.max(1, handins.size() / assignment.getpeercount());     int rng = new random().nextint(maxrng);      preparedstatement stmt = null;     connection con = null;      try{         //get connection, set transaction_serializable , set autocommit false         con = source.getconnection();         configureconnection(con);          //prepare statement insert new dispersion         stmt = con.preparestatement(insert_dispersion);         stmt.setstring(1, assignment.getid());          //iterate on hand-ins , decide peer peer receives feedback         for(int = 0; < handins.size(); i++)         {             handin handin = new handin(source.getconnection(), handins.get(i));             string student = handin.getemail();              stmt.setstring(2, student);              for(int j = 1; j <= assignment.getpeercount(); j++)             {                 handin otherhandin =  new handin(source.getconnection(), handins.get(j * rng));                 stmt.setstring(3, otherhandin.getid());                 stmt.executeupdate();             }         }          con.commit();     }catch(exception e){         throw e;     }finally{         closequietly(con, stmt);     } }  //this method in dbao class, put here folks. protected static void configureconnection(connection connection) throws sqlexception {     connection.setautocommit(false);     connection.settransactionisolation(connection.transaction_serializable); } 

this problem occurs in no other places in application. whenever run sql statement in sql server management studio, identical parameters, not stuck , inserts new rows fine. after deleting rows , trying same in application, gets stuck.

can point me in right direction of going wrong? i've been trying 3 hours straight now...

stuff tried

-use stmt.addbatch() rather executeupdate() (did not make difference. stuck @ executebatch())

-check if connections being closed properly; are.

-check if other statements/resultsets still open use revisiondispersion table (there none still open. if there were, should not make difference think?)

-completely delete database , set up

i solved issue...

in different piece of code had following:

private static final string get_not_dispersed = "select * assignments "                                             + assignments.close_date + "<=? , "                                              + assignments.peer_start_date + ">=? , "                                             + assignments.id + " not in(select " + assignments.id + " revisiondispersion)"; private void makemaildispersion() throws exception {     datetime currentdate = datetime.getcurrentdatetime();      preparedstatement assignmentsstmt = null;     resultset assignments = null;     connection con = null;      try{         con = source.getconnection();         configureconnection(con);         assignmentsstmt = con.preparestatement(get_not_dispersed);         assignmentsstmt.setstring(1, currentdate.tostring());         assignmentsstmt.setstring(2, currentdate.tostring());          assignments = assignmentsstmt.executequery();          arraylist<assignment> requiresdispersion = new arraylist<>();          assignments.close();         assignmentsstmt.close();         while(assignments.next())         {             assignment assignment = new assignment(source.getconnection(), assignments.getstring(assignments.id));             assignmentdisperser.disperse(source, assignment);         }     }catch(exception e){         throw e;     }finally{         closequietly(con, assignmentsstmt, assignments);     } } 

in piece of code, closed variables 'assignments' , 'assignmentsstmt'. thought sufficient unlock table after having used get_not_dispersed query. apparently not: table still locked.

what had in order fix it: aside calling assignments.close() , assignmentsstmt.close() had call con.close(). unlocked table , allowed code run properly.