which is the best option to validate if an ActionForm has changed?

[facundo martin rodriguez]

which is the best option to validate if an ActionForm has changed (the user changed one or more values in it inputs on the jsp) in Struts?

the ActionForm has a lot of instance variables, including lists.

[David Newton]

Maybe a hash code, if you don't need to know *what* changed?

[facundo martin rodriguez]

David Newton wrote:Maybe a hash code, if you don't need to know *what* changed?

your solution is very promising, but, i can't deal with the collisions of the hascode(), i haven't the 2 ActionForm's instance in the same time to applie the equal() method if i have a collisions with the hascode ( when i tell you collisions i refer to have the same hascode but with diferents values in the intance variables of the ActionForm's intances).

[David Newton]

Pass the original hashcode in the form submission.

If you're hashing correctly the chances of a collision are *extremely* small.

[facundo martin rodriguez]

David Newton wrote:Pass the original hashcode in the form submission.

If you're hashing correctly the chances of a collision are *extremely* small.

Hi David,

Thanks for your interest.

I don't have the code of the hasCode redefinition, i didn't do it yet. But my idea is get all the hashcode of the differents intance variables of the ActionForm and multiply that by a fix number (may be 13) and then add all .

May be something like that

    

int hasCode= (this.getMail1.hasCode()*13)  + (this.getMail2.hasCode()*13) .....

that is my ActionForm:

  public class FacturaElectronicaForm extends ActionForm {

	private String mail1;
	private String mail2;
	private String mail3;	
	private String[] alertasSeleccionadas;
	private String sms1;
	private String sms2;
	private String sms3;
	private String customerCode;
	private Long customerId;
	private Long idRegistroAtencion;
	private List<AlertaFacturaElectronica> alertas;
	private boolean adheridoAFe;//estado actual
	private boolean estadoAnteriorFE;//estado anterior de adhesion a FE
      .
      .
      .
	  

I can't allow any chance of collition, it is a core funcionality of the application.