ياربي انت العليم الحكيم

اخواني والله مللت من هده المشكلة

عندما احاول ان اقوم باضافة البيانات الى الجدول احصل على هده المشكلة

 اقصد جدول البيانات الموجود في phpmyadmin وانا اريد ان ادخل البيانات عن طريق الفورم التي انشئتها في netbeans
هل الخطا في القاعدة البيانية ام في الكود حفظ البيانات .وهده المشكلة :

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
    at closs.saveMouseClicked(closs.java:136)
    at closs.access$300(closs.java:6)
    at closs$4.mouseClicked(closs.java:84)
    at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:270)
    at java.awt.Component.processMouseEvent(Component.java:6508)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
    at java.awt.Component.processEvent(Component.java:6270)
    at java.awt.Container.processEvent(Container.java:2229)
    at java.awt.Component.dispatchEventImpl(Component.java:4861)
    at java.awt.Container.dispatchEventImpl(Container.java:2287)
    at java.awt.Component.dispatchEvent(Component.java:4687)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4501)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
    at java.awt.Container.dispatchEventImpl(Container.java:2273)
    at java.awt.Window.dispatchEventImpl(Window.java:2719)
    at java.awt.Component.dispatchEvent(Component.java:4687)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735)
    at java.awt.EventQueue.access$200(EventQueue.java:103)
    at java.awt.EventQueue$3.run(EventQueue.java:694)
    at java.awt.EventQueue$3.run(EventQueue.java:692)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
    at java.awt.EventQueue$4.run(EventQueue.java:708)
    at java.awt.EventQueue$4.run(EventQueue.java:706)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

 وهدا هو الكود المستعمل مع العلم اني قمت بالاتصال بالقاعدة وليست هناك مشكلة

 private void saveMouseClicked(java.awt.event.MouseEvent evt) {                                  
    String sql ="insert into las (id,nom,prenom)values(?,?,?)";
    try{
    st=con.prepareStatement(sql);
    st.setString(1,txtid.getText());
    st.setString(2,txtnom.getText());
    st.setString(3,txtprenom.getText());
    st.execute();
    JOptionPane.showMessageDialog(null, "save");
    
    
    }catch(Exception e){JOptionPane.showMessageDialog(null,e);}
    
    }