swing - INSERT stsement not working in java program -

hi have program connects embedded derby database , should reference database data. trying test database out using simple insert statement, not working. please help.

import java.awt.borderlayout;  import java.awt.eventqueue; import java.awt.label;  import javax.swing.jframe; import javax.swing.jpanel; import javax.swing.border.emptyborder; import javax.swing.jtabbedpane; import javax.swing.jlabel; import javax.swing.jtextfield; import javax.swing.buttongroup; import javax.swing.jcombobox; import javax.swing.jradiobutton; import java.awt.button; import java.awt.event.actionlistener; import java.awt.event.actionevent; import javax.swing.jbutton; import javax.swing.jlist; import java.awt.list; import java.sql.connection; import java.sql.drivermanager; import java.sql.resultset; import java.sql.sqlexception; import java.sql.statement; import java.sql.resultsetmetadata;  public class auto extends javax.swing.jframe implements actionlistener  {      /**      *       */     private static final long serialversionuid = -5777093322764526515l;     private jpanel contentpane;     private jtextfield f_name;     private jtextfield l_name;     private jtextfield f_name2;     private jtextfield l_name2;     private jtextfield age;     private jtextfield issuing;     private jtextfield liscense_num;     private jtextfield rental;     private jtextfield return_d;     private jtextfield total;     private jtextfield age2;     private jtextfield issuing2;     private jtextfield liscense_num2;     private jtextfield rental2;     private jtextfield return_d2;     private jtextfield total2;     private jtextfield agreement_id;     private button submit_button;     private button clear_button;     private jbutton load_button;     private button update_button;     private button return_car;     private jcombobox<?> car_select, car_select2;     private jradiobutton cc_button;     private jradiobutton cc_button2;     private jradiobutton debit_button;     private jradiobutton debit_button2;     private static string url;     private string com;     private static connection myconnection;     private static statement mystatement;       /**      * launch application.      */     public static void main(string[] args) throws sqlexception, classnotfoundexception {         eventqueue.invokelater(new runnable() {             public void run() {                 try {                     class.forname("org.apache.derby.jdbc.embeddeddriver");                     url = "jdbc:derby:mydb;create=true";                     myconnection = drivermanager.getconnection(url);                     mystatement = myconnection.createstatement( );                     auto frame = new auto();                     frame.setvisible(true);                 } catch (exception e) {                     e.printstacktrace();                 }              }         });     }      /**      * create frame.      */     public auto() {         setdefaultcloseoperation(jframe.exit_on_close);         setbounds(100, 100, 694, 497);         contentpane = new jpanel();         contentpane.setborder(new emptyborder(5, 5, 5, 5));         setcontentpane(contentpane);         contentpane.setlayout(null);          jtabbedpane auto_pane = new jtabbedpane(jtabbedpane.top);         auto_pane.setbounds(5, 5, 422, 432);         contentpane.add(auto_pane);          jpanel new_rent = new jpanel();         auto_pane.addtab("new rental", null, new_rent, null);         new_rent.setlayout(null);          jlabel first_name = new jlabel("first name: ");         first_name.setbounds(12, 8, 84, 16);         new_rent.add(first_name);          f_name = new jtextfield(15);         f_name.setbounds(97, 5, 116, 22);         new_rent.add(f_name);         f_name.setcolumns(10);          l_name = new jtextfield(15);         l_name.setbounds(97, 40, 116, 22);         l_name.setcolumns(10);         new_rent.add(l_name);          jlabel last_name = new jlabel("last name: ");         last_name.setbounds(12, 43, 84, 16);         new_rent.add(last_name);          jlabel age = new jlabel("age: ");         age.setbounds(12, 76, 84, 16);         new_rent.add(age);          age = new jtextfield(2);         age.setbounds(97, 75, 35, 22);         age.setcolumns(10);         new_rent.add(age);          jlabel liscense = new jlabel("license #: ");         liscense.setbounds(12, 113, 84, 16);         new_rent.add(liscense);           jlabel issuing_st = new jlabel("issuing state: ");         issuing_st.setbounds(12, 146, 84, 16);         new_rent.add(issuing_st);          issuing = new jtextfield(2);         issuing.setbounds(97, 143, 116, 22);         issuing.setcolumns(10);         new_rent.add(issuing);          liscense_num = new jtextfield(13);         liscense_num.setbounds(97, 110, 116, 22);         liscense_num.setcolumns(10);         new_rent.add(liscense_num);          string[] carstrings = { "compact", "midsized", "standard", "full size", "suv", "mini van" };         car_select = new jcombobox<object>(carstrings);         car_select.setbounds(97, 178, 112, 22);         new_rent.add(car_select);          jlabel car_type = new jlabel("car type:");         car_type.setbounds(12, 181, 84, 16);         new_rent.add(car_type);          jlabel rent_date = new jlabel("rental date:");         rent_date.setbounds(12, 216, 84, 16);         new_rent.add(rent_date);          rental = new jtextfield(10);         rental.setbounds(97, 213, 116, 22);         rental.setcolumns(10);         new_rent.add(rental);          jlabel return_date = new jlabel("return date:");         return_date.setbounds(12, 251, 84, 16);         new_rent.add(return_date);          return_d = new jtextfield(10);         return_d.setbounds(97, 248, 116, 22);         return_d.setcolumns(10);         new_rent.add(return_d);          jlabel total_num = new jlabel("total:");         total_num.setbounds(12, 283, 84, 16);         new_rent.add(total_num);          total = new jtextfield(7);         total.setbounds(97, 280, 116, 22);         total.setcolumns(10);         new_rent.add(total);          jlabel payment_type = new jlabel("payment type:");         payment_type.setbounds(12, 317, 100, 16);         new_rent.add(payment_type);          cc_button = new jradiobutton("credit card");         cc_button.setbounds(128, 313, 127, 25);         new_rent.add(cc_button);          debit_button = new jradiobutton("debit");         debit_button.setbounds(259, 313, 127, 25);         new_rent.add(debit_button);          buttongroup group = new buttongroup();         group.add(debit_button);         group.add(cc_button);          submit_button = new button("submit");         submit_button.setbounds(12, 356, 99, 24);         submit_button.addactionlistener(this);         new_rent.add(submit_button);          clear_button = new button("clear form");         clear_button.setbounds(128, 356, 99, 24);         clear_button.addactionlistener(this);         new_rent.add(clear_button);          jpanel current_rent = new jpanel();         auto_pane.addtab("current rental", null, current_rent, null);         current_rent.setlayout(null);          load_button = new jbutton("load current rental agreements");         load_button.addactionlistener(this);         load_button.setbounds(12, 13, 393, 25);         current_rent.add(load_button);          list load_list = new list();         load_list.setbounds(12, 54, 393, 229);         current_rent.add(load_list);          jpanel rental_ret = new jpanel();         auto_pane.addtab("rental details", null, rental_ret, null);         rental_ret.setlayout(null);          jlabel first_name2 = new jlabel("first name: ");         first_name2.setbounds(15, 48, 71, 16);         rental_ret.add(first_name2);          f_name2 = new jtextfield(15);         f_name2.setbounds(109, 45, 116, 22);         rental_ret.add(f_name2);         f_name2.setcolumns(10);          l_name2 = new jtextfield(15);         l_name2.setbounds(109, 74, 116, 22);         l_name2.setcolumns(10);         rental_ret.add(l_name2);          jlabel last_name2 = new jlabel("last name: ");         last_name2.setbounds(15, 77, 69, 16);         rental_ret.add(last_name2);          age2 = new jtextfield(2);         age2.setbounds(109, 109, 116, 22);         age2.setcolumns(10);         rental_ret.add(age2);          jlabel liscense2 = new jlabel("license #: ");         liscense2.setbounds(15, 141, 64, 16);         rental_ret.add(liscense2);           jlabel issuing_st2 = new jlabel("issuing state: ");         issuing_st2.setbounds(15, 170, 83, 16);         rental_ret.add(issuing_st2);          issuing2 = new jtextfield(2);         issuing2.setbounds(109, 167, 116, 22);         issuing2.setcolumns(10);         rental_ret.add(issuing2);          liscense_num2 = new jtextfield(13);         liscense_num2.setbounds(109, 138, 116, 22);         liscense_num2.setcolumns(10);         rental_ret.add(liscense_num2);           car_select2 = new jcombobox<object>(carstrings);         car_select2.setbounds(109, 197, 116, 22);         rental_ret.add(car_select2);          jlabel car_type2 = new jlabel("car type:");         car_type2.setbounds(15, 199, 57, 16);         rental_ret.add(car_type2);          jlabel rent_date2 = new jlabel("rental date:");         rent_date2.setbounds(15, 234, 71, 16);         rental_ret.add(rent_date2);          jtextfield rental2 = new jtextfield(10);         rental2.setbounds(109, 231, 116, 22);         rental2.setcolumns(10);         rental_ret.add(rental2);          jlabel return_date2 = new jlabel("return date:");         return_date2.setbounds(15, 269, 73, 16);         rental_ret.add(return_date2);          jtextfield return_d2 = new jtextfield(10);         return_d2.setcolumns(10);         return_d2.setbounds(109, 266, 116, 22);         rental_ret.add(return_d2);          jlabel total_num2 = new jlabel("total:");         total_num2.setbounds(15, 298, 34, 16);         rental_ret.add(total_num2);          jtextfield total2 = new jtextfield(7);         total2.setcolumns(10);         total2.setbounds(109, 295, 116, 22);         rental_ret.add(total2);          jlabel payment_type2 = new jlabel("payment type:");         payment_type2.setbounds(15, 332, 86, 16);         rental_ret.add(payment_type2);          cc_button2 = new jradiobutton("credit card");         cc_button2.setbounds(109, 328, 93, 25);         rental_ret.add(cc_button2);          debit_button2 = new jradiobutton("debit");         debit_button2.setbounds(220, 326, 57, 25);         rental_ret.add(debit_button2);          buttongroup group2 = new buttongroup();         group2.add(debit_button);         group2.add(cc_button);          jlabel age2 = new jlabel("age: ");         age2.setbounds(15, 112, 31, 16);         rental_ret.add(age2);          update_button = new button("update");         update_button.setbounds(15, 368, 83, 24);         rental_ret.add(update_button);         update_button.addactionlistener(this);          jlabel agreement = new jlabel("agreement id: ");         agreement.setbounds(15, 13, 93, 16);         rental_ret.add(agreement);          agreement_id = new jtextfield();         agreement_id.setcolumns(10);         agreement_id.setbounds(109, 10, 116, 22);         rental_ret.add(agreement_id);          return_car = new button("return car");         return_car.setbounds(109, 368, 83, 24);         rental_ret.add(return_car);         return_car.addactionlistener(this);     }        public void actionperformed(actionevent action) {                if(action.getsource() == submit_button){                   try {                       mystatement.execute("insert customer (fname, lname, age, licnum, state, car_type, rentdate, returndate, total, paytype, returned) values('tony','mahan', 56,'s622-400-55-400-0', 'ak', 'a', '2016-04-07', '2016-04-10', 213.47, 'credit', true)");                 } catch (sqlexception e) {                     // todo auto-generated catch block                     e.printstacktrace();                 }                }               if(action.getsource() == load_button);               if(action.getsource() == clear_button);               if(action.getsource() == return_car);               if(action.getsource() == update_button);       } } 

i not sure in insert command

 mystatement.execute("insert customer (fname, lname, age, licnum, state, car_type, rentdate, returndate, total, paytype, returned) values('tony','mahan', 56,'s622-400-55-400-0', 'ak', 'a', '2016-04-07', '2016-04-10', 213.47, 'credit', true)"); 

if have defined returned field in database varchar think last value true should in between ' ' -> 'true'