java - How can I handle this exception within this method? -

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i have jdbc connection code similiar following java jdbc tutorial:

public static void viewtable(connection con) throws sqlexception {     statement stmt = null;     string query = "select cof_name, sup_id, price, sales, total " + dbname + ".coffees";     try {       stmt = con.createstatement();       resultset rs = stmt.executequery(query);       while (rs.next()) {         string coffeename = rs.getstring("cof_name");         int supplierid = rs.getint("sup_id");         float price = rs.getfloat("price");         int sales = rs.getint("sales");         int total = rs.getint("total");         system.out.println(coffeename + "\t" + supplierid + "\t" + price + "\t" + sales + "\t" + total);       }     } catch (sqlexception e ) {       jdbctutorialutilities.printsqlexception(e);     } {       stmt.close();     }   }

my problem way of handling connection closes statement in finally block , method throws sqlexception may occur. don't want that, because want problems handled within class. however, do want statement#close() call in block closed.

right i'm placing code in separate method returns hashmap of fields returned exception handled in-class. there another, possibly better way handle this?

edit: close() sqlexception 1 concerned with. if possible i'd handle within method. write try/catch in finally, seems awkward.

you have several problems:

  • you need close resultset explicitly. drivers less forgiving forgetting close resultset others, doesn't hurt sure close it.

  • you ought catch sqlexception thrown statement.close, because it's not interesting , serves mask interesting exception (if have in method throw exception, throws exception on way out, exception block , lose first exception). there isn't can if close method call throws exception, log , go on, not concerned about.

  • you should give on idea of handling sqlexceptions in method, sqlexception thrown statement.executequery 1 worthwhile , ought propagated if goes wrong. it's other code in application want know if sql here succeeded or not , that's throwing exceptions for.

personally i'd suggest using library ibatis or spring-jdbc this. jdbc error-prone , tedious , it's better take advantage of existing tools.


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