question about ActionForm parameter of Action.execute() method
Can the ActionForm parameter of the Action.execute method be null? Under what circumstances will it be null and when will it be not-null? Is this described anywhere? In the struts-example source, some of the actions check the form parameter and will instantiate (and put it into scope) if it is null. Is that something that has to be done? Why doesn't Struts do the instantiation and putting into scope? Thanks, Kevin. __ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! http://platinum.yahoo.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: question about ActionForm parameter of Action.execute() metho d
--- Wendy Smoak [EMAIL PROTECTED] wrote: Kevin wrote: Can the ActionForm parameter of the Action.execute method be null? Under what circumstances will it be null and when will it be not-null? If there is no form bean associated with the action in struts-config.xml, then the ActionForm parameter will be null. And this association is done using the 'name' attribute of action to refer to a form-bean element? Thanks for your help, Kevin. __ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! http://platinum.yahoo.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: question about findForward()
--- Emmanuel Boudrant [EMAIL PROTECTED] wrote: You need a redirection. In a redirection, the request (who containt the form) is not propagate. Just put in forward declaration : forward name=toto path=/path_to_toto.jsp redirect=true/ If your form is stored in session scope, you need to call reset(); -emmanuel and --- Karr, David [EMAIL PROTECTED] wrote: Do you just mean you want to do a redirect? If so, you can do this without changing your code, just change the forward definition (in your action, or global) to have 'redirect=true'. Thank you both. The strange thing is, I tried the redirect attribute before I posted my question last night. I must have done something wrong because I tried it again this morning after seeing your responses and it works just as you said. As a note, it seems to work the same whether I reset() the form or not (it is in session scope). Emmanuel, why do you say that I need to call reset()? Thanks again, Kevin __ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
html:submit question
I have a couple of html:submit elements on one html:form. How do I distinguish between the different buttons? Specifically, I have html:submit property=operationEdit Loan/html:submit html:submit property=operationReject Loan/html:submit The form bean has a setOpereration(String) setter method which is called with the text of the button (ie, Edit Loan) when the form is submitted. When I look at the HTML that is rendered in the browser, I see that the property attribute becomes the name attribute of the input element. The way it works now, I have to compare the value of the operation property of the form bean against the string that is displayed to the user. That seems a bit fragile - suppose the customer wants the Reject Loan to be Cancel Loan instead. I'd have to change code in my action to effect the change. I'm looking for an attribute to html:submit that is the value that gets set to the property (operation). Is there such a thing. I want to avoid having a different form-bean-attribute for each submit tag (like operation1, operation2, etc.). Thanks, Kevin. __ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Re: html:submit question
--- Gemes Tibor [EMAIL PROTECTED] wrote: 2002. december 3. 16:30 dátummal Kevin HaleBoyes ezt írtad: The way it works now, I have to compare the value of the operation property of the form bean against the string that is displayed to the user. That seems a bit fragile - suppose the customer wants the Reject Loan to be Cancel Loan instead. I'd have to change code in my action to effect the change. Use LookupDispatchAction then. Wonderful! That is it exactly! Thanks Tib Kevin. __ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
question about findForward()
I'm having trouble explaining what I want but I'll have a go
of it anyway...
I'm in a Save action as a result of the POSTing of a form
via a html:cancel button. I do the test:
if (isCancelled(request)) {}
and detect the cancel. I'd like to go to another Action but
I don't want to propagate the POST. I want it to be a GET
where the input ActionForm is empty.
I'm calling
ActionForward forward = mapping.findForward(forwardName);
return forward;
to go to the new action but it propagates the POST.
Is there anyway turn the POST into a GET?
Should I just call form.reset() manually?
I hope this makes sense.
Kevin.
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how to handle empty form fields
I have a form field that is to represent a Date value. I input it using a html:text tag html:text property=assignedDate size=12/ and it corresponds to a String field in the form bean. It is an optional field and not usually filled in. In the business logic I call BeanUtils.copyProperties(lrdto, lrform); to copy from the form bean to the DTO. In the DTO the assignedDate property has the type java.sql.Date. When the field is left empty on the form I get a org.apache.commons.beanutils.ConversionException exception from copyProperties() that was generated by SqlDateConverter. I'm wondering how to avoid the exception. If I set a value into the field before I submit the form then it works fine. I only run into the exception when I leave the field blank but my business requirements state that this field is optional. There are a __lot__ of questions regarding Date input and validation in the archives but I didn't find anything about this exception or optional Date fields. Thanks for any help, Kevin. __ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
question about empty form fields
I have a FormBean that has all strings as the datatypes. I then have a DTO bean that has the proper datatypes for the different properties - java.sql.Date, int, etc. In my JSP form I have an input field that is supposed to represent a date field. It is not a required field. I'm not using the Validator framework. html:text property=assignedDate size=12/ So, when the form is submitted with the assignedDate field have not been set, the value in the FormBean is the empty string . After validating the fields in the FormBean, I call BeanUtils.copyProperties() to move the values from the FormBean into the DTO but I get a ConversionException on this empty field. I've attached the exception report below. If I fill in the field with a properly formed date then everything works fine. It is only when I leave the field empty that I get the exception. Am I doing something I shouldn't? Just as an empty string field is valid and handled properly, I feel that an empty date field is valid and should be handled properly. How can I fix it? I could check the value of the date fields and if they are empty then I could set them to null (which SqlDateConverter handles correctly) but this is a hack! I could also register my own converter that handles an empty string for input but I feel that this is such a common use case for input date strings I'm confused that it isn't handled. Thanks for any help, Kevin. org.apache.commons.beanutils.ConversionException at org.apache.commons.beanutils.converters.SqlDateConverter.convert(SqlDateConverter.java:162) at org.apache.commons.beanutils.BeanUtils.copyProperty(BeanUtils.java:359) at org.apache.commons.beanutils.BeanUtils.copyProperties(BeanUtils.java:265) at com.illuminat.cml.LoanRequestSaveAction.execute(LoanRequestSaveAction.java:130) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:446) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:266) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1292) at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:510) at javax.servlet.http.HttpServlet.service(HttpServlet.java:760) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at com.illuminat.cml.IdentityFilter.doFilter(IdentityFilter.java:101) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:260) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:527) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2396) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:469) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at
Re: struggling with indexed/repeating input fields
From: Leonardo Maciel [EMAIL PROTECTED] I GOT IT! I forgot to send the struts-config.xml and there were the difference VERY-IMPORTANT if I set the action scope=request I get: javax.servlet.ServletException: BeanUtils.populate ... Caused by: java.lang.IndexOutOfBoundsException: Index: 2, Size: 0 or Caused by: java.lang.NullPointerException make sure you don't have scope=request in your action ... /action /VERY-IMPORTANT You have really made my day!!! Thanks. I took the code you gave me and the code from the original link (yes, thanks Dave). I couldn't get either of them to work since I just automatically put in the scope=request into the configuration entry. I was getting a similar error message: javax.servlet.ServletException: BeanUtils.populate at org.apache.struts.util.RequestUtils.populate(RequestUtils.java:980) at org.apache.struts.action.RequestProcessor.processPopulate(RequestProcessor.java:779) ... - Root Cause - java.lang.ArrayIndexOutOfBoundsException: 0 = 0 at java.util.Vector.elementAt(Vector.java:427) Which is similar to every other attempt I've made. The array/vector/list/collection wasn't initialized to have the correct size before the indexed setters were called. I kind of consider it to be a bug in BeanUtils but I'm not sure. It would never have occurred to me that the scope would effect it. As soon as I made that change and restarted, it worked! I've not tried the nested tags but I suspect the crucial element is the scope of the form bean. I do agree with [EMAIL PROTECTED] about having to put the bean into session scope - I'll have to manage that very carefully or implement the indexed setter that you gave and that Jim Krygowski mentioned. I'll also look at the lazyList from Commons Collection. Thanks again! Also, thanks to everyone else who helped. Kevin. __ Do you Yahoo!? Yahoo! Web Hosting - Let the expert host your site http://webhosting.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
struggling with indexed/repeating input fields
I've asked this question several times on this mailing list but I've never received an answer that would help. I've dug a bit deeper and understand more about the problem but I'm still really struggling with indexed/repeating input fields so I thought I'd ask again. I'm starting to wonder if it is possible. In my ActionForm I have an array property that is initialized to null (I don't know the values until the Action executes). I have a getter that returns the entire array and a setter that takes an array. I also have indexed getters and setters. The array is of another class (that simply has two strings in it with the default/empty constructor and getters and setters). In my (edit) action I construct an array and call the setter in the action form instance (that I just created). I then forward to a JSP page that has a logic:iterate tag and html:text tags all within a form tag. The form has a html:submit that calls my save action. The save action simply forwards to a confirmation JSP page that has a similar iteration to display the input values. The initial edit form gets displayed properly - the expected number of iterations are performed and the expected values of the input fields is shown. When I press the submit button things break. I know that isn't terribly descriptive but how it breaks depends on how I form the html:text tags - there are two cases that I've tried. In the first case, I use the following in the edit JSP form: logic:iterate id=li name=IndexedForm property=lineItem html:text name=li property=itemNo indexed=true/ html:text name=li property=desc indexed=true/ /logic:iterate As I said, it displays properly. I change the desc text and hit the submit button and end up getting an exception: ApplicationDispatcher[/cml] Servlet.service() for servlet jsp threw exception org.apache.jasper.JasperException: No collection found In the save action I printed the toString() of the input form before forwarding to the JSP page and can see that the array is in fact null. Why is it null? Who is responsible for instantiating an array for that field - struts or the application? If it is the application, how can it know how big to make the array? In the second case, I use the following in the edit JSP form: logic:iterate id=li name=IndexedForm property=lineItem indexId=i % String prop1 = lineItem[ + i + ].itemNo; % html:text property=%= prop1 % size=30/ % String prop2 = lineItem[ + i + ].desc; % html:text property=%= prop2 % size=30/ /logic:iterate Again, it displays properly. I change the desc text and hit the submit button and end up getting an exception: StandardWrapperValve[action]: Servlet.service() for servlet action threw exception javax.servlet.ServletException: BeanUtils.populate ... Caused by: java.lang.NullPointerException at com.illuminat.cml.IndexedForm.getLineItem(IndexedForm.java:286) This happens even before it calls the save action. So, I'm at a loss as to how to handle indexed or repeating fields. I've looked at the code in html-setters.jsp and TestBean from the exercise-taglib in the distribution but that uses fixed size arrays and static initializers. It hasn't been simple to go from that to a variable number of array elements and non-static (from a database) initialization. I've also looked in the archives and on the current mailing list and found nothing. Actually, I've been seeing more questions regarding indexed properties lately (mostly using DynaBeans) but they are generally going un-answered or not coming up with solutions, just more questions. This is not a complaint as I know everyone is very busy but it does mean that I've not found anything in the archives. Help would be most appreciated. Sample code would be even nicer! Is it even possible with Struts (version 1.1b2)? I can furnish code or a better explaination if needed. Kevin __ Do you Yahoo!? Yahoo! Web Hosting - Let the expert host your site http://webhosting.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
need help with indexed properties
I have a Forms Bean
public class IndexedForm {
private String items[] = new String[] {one, two};
public String[] getItems() { return items; }
public void setItems( String[] v ) { items = v; }
}
and a JSP page to display/edit the items:
logic:iterate id=i name=IndexedForm property=items
bean:write name=i/ br
html:text property=items indexed=true/
/logic:iterate
The bean:write tag displays the contents correctly but
the html:text tag doesn't. Instead, I get
[Ljava.lang.String;de530a
which looks like the address of the items array.
Why doesn't this work?
I've tried adding indexed getters and setters but that didn't
work. I've also searched the archives since this seems like a
common problem but I've not come across an answer - similar things
but nothing that shed any light on my problem.
In fact this
http://www.mail-archive.com/struts-user;jakarta.apache.org/msg47247.html
is very similar but there was never a reply to the last post.
I'm running Struts 1.1b2 on Tomcat 4.1.10.
I'm really at a loss and would appreciate any help.
Kevin.
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repeating input fields
I know this has been asked before but I'm unable to find anything
in the archive - probably not using the right search terms...
I'm trying to create a form that allows the user to input a list
of strings. Kind of like a detail block (of a master-detail
relationship).
So I have
public class LoanPurpose {
private String id;
private String description;
public String getId() {return id;}
public void setId( String v ) { id = v; }
public String getDescription() {return description;}
public void setDescription( String v ) {description = v;}
}
and a Form bean
public class LoansForm extends ActionForm {
private LoansPurpose[] purposes = null;
public LoanPurpose[] getPurposes() {return purposes;}
public void setPurposes( LoanPurpose[] v ) {purposes = v;}
public void reset(ActionMapping mapping,
HttpServletRequest request) {purposes = null;}
}
In my JSP form I have:
html:form action=/saveLoanPurps method=post
table
logic:iterate id=p name=LoansForm property=purposes
trtd
html:text name=p property=id size=15/
/tdtd
bean:write name=p property=description filter=true/
/td/tr
/logic:iterate
/table
html:submitSave/html:submit
/html:form
If I stuff a few values into the purposes array in the edit
action they properly get displayed when the form is rendered.
This is where I get lost though. When I hit the Save submit
button I don't get the results I expect. In the Save action I
print the contents of the LoansForm.purposes array and it is null,
instead of having the contents of the input fields.
What am I missing?
Any help would be most appreciated.
Thanks,
Kevin.
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RE: repeating input fields
instead of:
property=id
property=description
use:
property=purposes[1].id
property=purposes[1].description
That makes sense! I made the changes to the JSP file and also
added indexed getter/setter to the form bean.
public class LoansForm extends ActionForm {
private LoansPurpose[] purposes = null;
public LoanPurpose[] getPurposes()
{return purposes;}
public void setPurposes( LoanPurpose[] v )
{purposes = v;}
public LoanPurpose getPurposes( int idx )
{return purposes[idx];}
public void setPurposes( int idx, LoanPurpose v )
{purposes[idx] = v;}
public void reset(ActionMapping mapping,
HttpServletRequest request) {purposes = null;}
}
But now when I submit the Save I'm getting an exception
javax.servlet.ServletException: BeanUtils.populate
...
- Root Cause -
java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor16.invoke(Unknown
Source)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at
org.apache.commons.beanutils.PropertyUtils.getIndexedProperty(PropertyUtils.java:475)
at
org.apache.commons.beanutils.PropertyUtils.getIndexedProperty(PropertyUtils.java:410)
at
org.apache.commons.beanutils.PropertyUtils.getNestedProperty(PropertyUtils.java:749)
at
org.apache.commons.beanutils.PropertyUtils.getProperty(PropertyUtils.java:780)
at
org.apache.commons.beanutils.BeanUtils.setProperty(BeanUtils.java:793)
at
org.apache.commons.beanutils.BeanUtils.populate(BeanUtils.java:726)
at
org.apache.struts.util.RequestUtils.populate(RequestUtils.java:978)
Caused by: java.lang.NullPointerException
at
com.illuminat.cml.LoansForm.getPurposes(LoansForm.java:1420)
... 49 more
(obviously, I've trimmed the exception report)
Line 1420 of LoansForm.java is the indexed getter. So my purposes
array is null and I'm trying to get the value at a particular index
(idx=3 in this test run).
The array is null because I set it to that in the reset() method.
That's what I'm supposed to do though, isn't it?
How can I know to allocate the array and what size it should be?
I'm missing something here! For instance, I'm executing a Save
so why is the indexed getter being called and not the indexed
setter?
This should get you started...
It did indeed, and I thank you for that. Unfortunately, it has
raised more questions and I'm at a loss as to how to proceed!
Thanks again,
Kevin
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RE: struts-config.xml question
Victor and Emmanuel, thanks for your answers. With them, and the later discussion on similar topics I think I understand. Part of my confusion comes from a bug I've not been able to repeat. At one point in time I changed the 'attribute' property to 'name' and my application stopped working. It seems that I had done something else (not sure what) and the problem had nothing to do with using 'name'. I've just tried to repeat it in isolation and I can't. Again, thanks. Kevin. __ Do you Yahoo!? New DSL Internet Access from SBC Yahoo! http://sbc.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
RE: EL and the developer's roadmap
First time I've heard of EL too. Where can I get more info? Others have already noted http://java.sun.com/products/jsp/jstl/index.html Also have a look at a couple of OnJava articles (the printable versions) http://www.onjava.com/lpt/a/2611 http://www.onjava.com/lpt/a/2610 Kevin. __ Do you Yahoo!? New DSL Internet Access from SBC Yahoo! http://sbc.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
struts-config.xml question
I'm looking at the struts-example and its struts-config.xml file. In the action section for editRegistration, 'attribute' is set to 'registrationForm'. As I understand it (from the DTD), attribute is the name of the scoped (session or request) attribute that is used to access the ActionForm bean. Now in the action section for saveRegistration 'name' is set to 'registrationForm'. 'name' is the name of the form bean that is associated with this mapping. What is the difference between 'attribute' and 'name'? It seems that they are the same thing. Is this true? Looking at the source for the edit and save registration actions, they both call mapping.getAttribute() to get the name of the ActionForm bean. Why does that work for the saveRegistration action when it doesn't even have an 'attribute' defined for its action? Why doesn't saveRegistration use 'attribute' instead of 'name'? Thanks, Kevin. __ Do you Yahoo!? New DSL Internet Access from SBC Yahoo! http://sbc.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Re: MVC and Struts
Jin, thank you very much for your help. A question based on something you said... Your Xform would do basic validation ie format/type checking. The business validation of the values would be done in Xmaintainence. I've actually not implemented the validate() method of the (struts) form (XForm). In some cases the format and type of a field requires knowledge of the business logic. All of the fields in XForm are strings but do represent other data types. There is a date field for example. Should XForm really know that the takenOn field is a date? Should XForm really know that the takenOn field is required? I'm not so sure that XForm should know anything like that. Maybe it should but what if we consider a different, more complex, field. Maybe my XForm needs to collect a WidgetId field as input. WidgetIds are very specific to my business and the format and type of them probably differs from your WidgetIds. If I have XForm check the format or type of the incoming WidgetId then my view component knows a little too much about my model. Again, thanks for your help. Kevin. __ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
MVC and Struts
I have a struts application modelled after the struts-example.
It has
XForm.java as the form bean,
x.jsp to display the form, and
EditXAction.java and SaveXAction.java to process the actions.
Edit and Save actions need to use an XMaintainance class as it
provides the knowledge of the business logic.
In SaveXAction I've checked to make sure the request wasn't cancelled
and checked the transaction token (normal struts stuff). I need to
do additional validations when an XForm is being created so I've
added a validate() method to XMaintainance.
So the SaveXAction code does something like the following:
ActionErrors errors = new ActionErrors();
XForm xf = (XForm)form;
XMaintainance xm = new XMaintainance();
if ( ! xm.validate(xf) ) {
errors.add(error, new ActionError(Xerrors));
}
and later check to see if there have been any errors, and if so,
saveErrors() and saveToken() are called and we forward back to the
mapping.getInput().
That works great!
My question is:
XForm is considered to be a View component.
SaveXAction is considered to be a Controller component.
XMaintainance is a Model component.
By passing the XForm to XMaintainance haven't I mingled the two
components when there was no need? Mingled is the wrong word.
Instead,
SaveXAction could mediate the interaction between the view and
the model by copying values from the view into the controller:
xm.setXFormField1( xf.getField1() );
...
if ( ! xm.validate() ) {
errors.add(error, new ActionError(Xerrors));
}
Performance wise it would be wasteful to copy the values from
XForm to XMaintainance. But isn't one of the goal of MVC to
separate the Model from the View by way of the Controller?
Where do we make the split between the three components?
For instance,
how do report errors from XMaintainance? I could change the
code above to be:
ActionErrors errors = new ActionErrors();
XForm xf = (XForm)form;
XMaintainance xm = new XMaintainance();
if ( ! xm.validate(xf, errors) ) {
errors.add(error, new ActionError(Xerrors));
}
But now I've mingled a core Controller element (ActionError) to
the Business logic layer. If I don't do this though, I'll have to
use something similar to ActionErrors that XMaintainance knows about.
SaveXAction would have to copy these errors to the Struts
ActionErrors. It seems like a lot of copying is being done in order
to separate the components.
Does any of this make any sense? I guess I'm looking for advice,
on how to split the three MVC components and pass information
between the layers.
Thanks,
K.
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