Struts: JSP, Form and Action relationship

Struts: JSP, Form and Action relationship

1. Create:  (or convert an HTML page)
	JSP page  (Presentation layer on Browser)
		     (using struts tags) 
	add at least these 3 struts tag libraries at top before the <html> tag: 
		<%@ taglib uri="/WEB-INF/taglib/struts-bean.tld" prefix="bean" %>
		<%@ taglib uri="/WEB-INF/taglib/struts-html.tld" prefix="html" %>
		<%@ taglib uri="/WEB-INF/taglib/struts-logic.tld" prefix="logic" %>
	sometimes this one too:
		<%@ taglib uri="/WEB-INF/taglib/struts-nested.tld" prefix="nested" %>
	may need tags more - at times...
	
	change any <form> tags to
		<html:form action="/listSomething" method="get">  
		  (must be the same as <action path="/" in struts-config)
	add tags to view data held in ValueObject
		<bean:write name="someValueObject" property="someFieldName"/>


2. Create:
	Form Class  (Form.java)  (Form.class runs on Server)
	<form-bean .../>
	extends from ActionForm 	(a struts class)
	*default constructor
		sop("—someForm.constructed()—");
	*overwrite validate();		(for form level validations)
		preValidate(request);   (if needed)
		ActionErrors errors = new ActionErrors();
		return errors;
	*overwrite toString();
	
	(if needed...)
	*someValueObject 	(declare instance variable of ValueObject, 
	                          populate it with values from browser or database)
	*setters and getters for each parameter used
		someValueObject.fieldNames (parameters used/passed)
		action
	


3. Create:
	Action Class  (Action.java)  (Action.class runs on Server)
	extends from Action 	(a struts class)
	*overwrite execute();  	(core of the code...)
		sop("—someAction.execute()—");
		ActionForward forward = null;
		SomeForm someForm = (SomeForm)form;
		String action = someForm.getAction();
		forward = mapping.findForward("nextPage");  
		  (same as in <forward name="nextPage" in <action-mappings>)
		return forward;
	-Business rules     (for business logic validations)
	-Database connections & actions  
		(get/sets from SomeHandlerImpl.java using SomeValueObject.java)

4. Define <form-bean name="someForm".../> 
	in struts-config.xml

5. Define <action-mapping> <action path="" name="someForm" <forward name="nextPage" 
	in struts-config.xml
(<form-bean name="" must be exactly the same as <action name="")

struts-config.xml  "ties"  1-3 together with 4&5

More information: Apache struts , struts-api , java-api , struts-html , struts-bean , struts-logic , Husted struts , KeyBoardMonkey

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Lu's Notes

Struts: JSP, Form and Action relationship