Java GUI example

// This is from Student.java
public static void javaOracleDelete(String sql)throws Exception,SQLException {
        String user = "jtan";
        String pass = "jtan";
        String dbUrl = "jdbc:oracle:thin:@localhost:1521:XE";
        Connection myConn = DriverManager.getConnection(dbUrl,user,pass);
        Statement myStmt = myConn.createStatement();
        try{
            myStmt.executeUpdate(sql);
            System.out.println("Row is deleted!");
        }
        catch(Exception e){System.out.println("Row is not deleted!");}
    }

    public static void javaOracleInsert(String sql)throws Exception,SQLException {
        String user = "jtan";
        String pass = "jtan";
        String dbUrl = "jdbc:oracle:thin:@localhost:1521:XE";
        Connection myConn = DriverManager.getConnection(dbUrl,user,pass);
        Statement myStmt = myConn.createStatement();
        try{
            myStmt.executeUpdate(sql);
            System.out.println("New row is inserted!");
        }
        catch(Exception e){System.out.println("New row is not inserted!");}
    }

    public static void javaOracleUpdate(String sql)throws Exception,SQLException {
        String user = "jtan";
        String pass = "jtan";
        String dbUrl = "jdbc:oracle:thin:@localhost:1521:XE";
        Connection myConn = DriverManager.getConnection(dbUrl,user,pass);
        Statement myStmt = myConn.createStatement();
        try{
            myStmt.executeUpdate(sql);
            System.out.println("Row is updated!");
        }
        catch(Exception e){System.out.println("Row is not updated!");}
    }

//StudentFrame.java
private void btnUpdateActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnUpdateActionPerformed
        String sql = "UPDATE STUDENT \n" +
                        "SET STUDENT_FNAME='"+this.txtUpdateFname.getText()+"', STUDENT_LNAME='"+this.txtUpdateLname.getText()+"' \n" +
                        "WHERE STUDENT_USN='"+this.txtUpdateUSN.getText()+"'";
        try {
            Student.javaOracleUpdate(sql);
            refreshTable();
            JOptionPane.showMessageDialog(null,"Updated Successfully!");
        } catch (Exception ex) {
            Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

private void btnCreateActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnCreateActionPerformed
        String sql = "INSERT INTO STUDENT VALUES\n" +
                        "(\n" +
                        "    '"+this.txtCreateUSN.getText()+"',\n" +
                        "    '"+this.txtCreateFname.getText()+"',\n" +
                        "    '"+this.txtCreateLname.getText()+"'\n" +
                        ")\n";
        try {
            Student.javaOracleInsert(sql);
            refreshTable();
            JOptionPane.showMessageDialog(null,"Created Successfully!");
        } catch (Exception ex) {
            Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

private void btnDeleteActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnDeleteActionPerformed
        String sql = "DELETE STUDENT\n" +
        "WHERE STUDENT_USN='"+this.txtDeleteUSN.getText() +"'";
        try {
            Student.javaOracleDelete(sql);
            refreshTable();
            JOptionPane.showMessageDialog(null,"Deleted Successfully!");
        } catch (Exception ex) {
            Logger.getLogger(StudentFrame.class.getName()).log(Level.SEVERE, null, ex);
        }
    }


public void refreshTable(){
        entityManager = java.beans.Beans.isDesignTime() ? null : javax.persistence.Persistence.createEntityManagerFactory("jdbc:oracle:thin:@localhost:1521:XEPU").createEntityManager();
        studentQuery = java.beans.Beans.isDesignTime() ? null : entityManager.createQuery("SELECT s FROM Student s");
        studentList = java.beans.Beans.isDesignTime() ? java.util.Collections.emptyList() : studentQuery.getResultList();

        org.jdesktop.swingbinding.JTableBinding jTableBinding = org.jdesktop.swingbinding.SwingBindings.createJTableBinding(org.jdesktop.beansbinding.AutoBinding.UpdateStrategy.READ_WRITE, studentList, jTable1);
        org.jdesktop.swingbinding.JTableBinding.ColumnBinding columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${studentUsn}"));
        columnBinding.setColumnName("Student Usn");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${studentFname}"));
        columnBinding.setColumnName("Student Fname");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${studentLname}"));
        columnBinding.setColumnName("Student Lname");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        bindingGroup.addBinding(jTableBinding);
        jTableBinding.bind();
        jScrollPane1.setViewportView(jTable1);
    }