why do I get : Exception in thread “AWT-EventQueue-0” java.lang.RuntimeException: Uncompilable source code – illegal start of expression

private void Client_Save_jButton9ActionPerformed(java.awt.event.ActionEvent evt) {

if (!="".equals(DNI_Client_jTextField8.getText()) || !="".equals(Name_Client_jTextField9.getText()) || !="".equals(Phone_Client_jTextField10.getText()) || !="".equals(Address_Client_jTextField11.getText()) ){
                cl.setDni(DNI_Client_jTextField8.getText());
                cl.setNombre(Name_Client_jTextField9.getText());
                cl.setTelefono(Phone_Client_jTextField10.getText());
                cl.setDireccion(Address_Client_jTextField11.getText());
                cl.setRazon(Razon_Social_Client_jTextField12.getText());
                client.RegistrarCliente(cl);
                JOptionPane.showMessageDialog(null, "your textRegister Client");
        }else{
            JOptionPane.showMessageDialog(null, "The fields are empty");
        }


}