private static final long serialVersionUID = 1L;

public static boolean validate(String username,String password,String npass) {

    boolean status = false;
    ChangePass cp = new ChangePass();
    try {
        Connection con = DBConnection.getConnection();
        PreparedStatement ps = con.prepareStatement("select * from doctable where username=? and password=?");

        ps.setString(1, username);
        ps.setString(2, password);

        ResultSet rs= ps.executeQuery();
        status = rs.next();
        if(true) {
            PreparedStatement ps1 = con.prepareStatement("update details set password=? where username=?");
            ps1.setString(1, cp.getNpass());
            ps1.setString(2, cp.getUsername());
            ps1.executeUpdate();
        }
    }

    catch (Exception ex) {
        ex.printStackTrace();

        return status;
    }
    return status;
}