java Sqlit删除确实'；不起作用

这是我的代码，我调试并检查了很多，但我不明白为什么这不起作用。请帮我一个。

   if (msg.equals("succes")) 
  {
   Connection c = null;
   Statement stmt = null;
   Class.forName("org.sqlite.JDBC");
   c = DriverManager.getConnection("jdbc:sqlite:C:''Users''pk''Documents''NetBeansProjects''HRMS''employee.sqlite");
   c.setAutoCommit(false);
   stmt = c.createStatement();
   String sql = "DELETE FROM attendance";
   stmt.executeUpdate(sql);
   stmt.execute(sql);
   System.out.println(sql);
   JOptionPane.showMessageDialog(null, "data are sent to server and deleted from local sqlite");
   rs.close();
   stmt.close();
   c.close();
  } 
   else 
  {
   JOptionPane.showMessageDialog(null, msg);
  }