Struts dynamic form application

This article explains the reference of DYNAFORMS in Struts1.1 in an instance code ?? Translator's note

If you have used Struts Previous versions, you will notice that you need to spend a lot of time to write an actionform class file, and these types of files are very critical for Struts (it acts as part of "View"), usually it The structure is Bean Properties plus a validate method (sometimes reset method).

With the launch of the Struts1.1, the developer has another way to complete the previous tasks: use Dynabeans. Dynabeans dynamically generate Java Beans. This means that we can configure (usually using XML)

To generate FormBean instead of hard coding in FormBean.

To learn how Dynabeans (Struts is DynaForms), let's take a simple form, the fields are: Name, Address, Telephone, etc., the following code is the usual way of writing (not using DynaForms).

Article1.customerform

Package article1;

import org.apache.struts.action.ActionForm; import org.apache.struts.action.ActionErrors; import org.apache.struts.action.ActionMapping; import org.apache.struts.action.ActionError; import javax.servlet.http .HttpservletRequest;

Public class customerform extends actionform {

protected boolean nullOrBlank (String str) {return ((str == null) || (str.length () == 0));} public ActionErrors validate (ActionMapping mapping, HttpServletRequest request) {ActionErrors errors = new ActionErrors (); IF (NullBLANK (Lastname)) {Errors.Add ("LastName", New Actionerror ("Article1.lastname.Missing"));}}} (Nulloblank (Firstname)) {Errors.Add ("Firstname", New Actionerror (" Article1.firstname.Missing "));} {Errors.Add (" street ", new actionerror (" article1.street.missing ");}} f (nulloblank (city) {Errors. Add ("City", New Actionerror ("Article1.city.Missing"));}} (NullorBLANK (State)) {Errors.Add ("State", New Actionerror ("Article1.State.Missing");} IF (NULLORBLANK ("Postalcode", new actionerror ("article1.postalcode.missing));}} f (Nulloblank (Phone) {Errors.Add (" Phone ", New Actionerror (" Article1.phone.missing "));} Return Errors; Private String Firstname; Private String Street; Private Stri Ng city; private string postalcode; private string phone; privat

Public string getlastname () {return Lastname;}

Public void setlastname (String lastname) {this.lastname = lastname;

Public string getfirstname () {return firstname;}

Public void setfirstname (string firstname) {this.firstname = firstname;}

Public string getStreet () {return street;}

Public void setstreet (string street) {this.street = street;

PUBLIC STRING GETCITY () {Return City;}

Public void setcity (string city) {this.city = city;}

Public string getState () {return state;}

Public void setState (string state) {this.state = state;} public string getpostalcode () {return postalcode;}

Public void setpostalcode (string postalcode) {this.postalcode = postalcode;

Public String getphone () {return phone;}

Public void setphone (string phone) {this.Phone = phone;}}

Seeing the write method in the upper side (such a long code [Although most of the tools can automatically generate SET and GET methods] What is it? If you want to match a formbean for each form, then a painful thing? ? Translator's note), you know that it is a standard JavaBean, just a validate method, the Validate method ensures that the Client break is legal.

The corresponding JSP page is also very simple, as follows:

Customer.jsp

<% @ Taglib Uri = "/ Web-INF / C.TLD" prefix = "c"%> <% @ Taglib prefix = "FMT" URI = "/ Web-INF / FMT.TLD"%> <% @ Taglib URI = "/ Web-inf / struts-tiles.tld" prefix = "tiles"%> <% @ taglib URI = "/ web-inf / struts-html.tld" prefix = "html"%>