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Posted to user@struts.apache.org by "Givler, Eric" <eg...@state.pa.us> on 2006/10/11 20:32:56 UTC
Code reduction for Action classes
I've been trying to get the hang of struts now for the past few months, and am wondering how people write "re-usable" base classes for Struts. If you have the time, I'd really appreciate your thoughts on this - bear with me, as it's a lot of reading:
My actions tend to be "similar" but making them "reusable" seems to be eluding me.
What I would like to have is a set of reusable actions that handle the following standard application features:
1. A wizard (multiple jsps, one form bean, data formatting, validation specific per page, with persistence when any navigation occurs, not just at the end). I've seen an example of an "at-the-end" wizard in the sample Chapter from Struts Recipes by George Franciscus and Danilo Gurovich.
2. A multi-record screen ( one jsp, array of items, formatting of data, validation w/ messages, and persistence)
Are these already written, so I can save some time?
So far, I've tried to write a re-usable piece of code for #2.
Based on ideas in the ObjectSource Struts Survival Guide, Chapter 10:
#1: I wrote my own mapping. Here are the properties:
public class CRUDActionMapping extends ActionMapping{
private String formType;
private String formMultiRecordProperty;
private String formDefConfig;
private String databaseBeanClassName;
private String saveServiceMethod;
private String retrieveServiceMethod;
private String serviceName;
#2: My struts-config.xml for the action for this class is defined as:
<action path="/cbdeqr_engcodehours"
className="dep.ccdreporting.view.mappings.CRUDActionMapping"
type="dep.ccdreporting.view.actions.cbp.CbdeqrEngCodeHoursAction"
name="CbdeqrEngCodeHoursForm"
input="/WEB-INF/jsp/cbp/cbdeqr_engcodehours.jsp"
scope="session"
validate="false"
parameter="event_save=save,event_codehours=initializePage,
event_reportInProgress=previous,event_countyHours=next,
default=unspecified">
<set-property property="cancellable" value="true"/>
<set-property property="formType" value="MultiRecord"/>
<set-property property="formMultiRecordProperty" value="codehours"/>
<set-property property="formDefConfig" value="CbdeqrEngCodeHoursForm"/>
<set-property property="databaseBeanClassName" value="dep.ccdreporting.model.vo.cbp.CbdeqrCodeHours"/>
<set-property property="saveServiceMethod" value="saveCbdeqrCodeHours"/>
<set-property property="retrieveServiceMethod" value="getEngCodeHours"/>
<set-property property="serviceName" value="dep.ccdreporting.model.service.cbp.CBPDaoService"/>
<forward name="hourspercounty" path="/cbdeqr_engcountyhours.do"/>
<forward name="cbdeqr_main" path="/cbdeqr.do"/>
<forward name="success" path="/WEB-INF/jsp/cbp/cbdeqr_engcodehours.jsp"/>
</action>
#3: The action class CbdeqrEngCodeHoursAction is reduced to two overridden methods (save and initializePage, due to calling a calculation) of a base class, and one method that gets the parameters to retrieve the data, which is:
public HashMap getRetrieveServiceMethodParams( HttpServletRequest request ) {
HttpSession session = request.getSession();
UserBean userbean = (UserBean) session.getAttribute("usrbean");
HashMap codeparams = new HashMap();
codeparams.put("report_id" , userbean.getReport_id());
return codeparams;
} // getRetrieveServiceMethodParams
#4: The base class handles the initialization of the page and the save. Here's the save() call so this message doesn't get too wordy:
public ActionForward save(ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
throws Exception,
ServletException
{
ActionForward fwd = mapping.getInputForward();
if (isFormValid(mapping, form, request)) {
if ( mapping instanceof CRUDActionMapping ) {
CRUDActionMapping myMapping = (CRUDActionMapping) mapping;
if (myMapping.getFormType().equalsIgnoreCase("MULTIRECORD")) {
saveMultiRecordForm ( mapping, form, request );
...
and the save code -- this is where I'm confused - is this a reasonable approach, or am I really missing the boat. Specifically: Should I be creating the service like this? Also, I really want the ability to log who is performing the service methods as well - i.e. request.getRemoteUser(), so do I have to pass this to the service method, or can I get it another way??
public void saveMultiRecordForm ( ActionMapping mapping,
ActionForm form,
HttpServletRequest request )
throws Exception
{
// get all the action-mapping properties
CRUDActionMapping crudMapping = (CRUDActionMapping) mapping;
String formPropertyName = crudMapping.getFormMultiRecordProperty();
String formDefConfigName = crudMapping.getFormDefConfig();
String databaseBeanClass = crudMapping.getDatabaseBeanClassName();
String saveServiceMethodName = crudMapping.getSaveServiceMethod();
// form-def returns an array of dynaActionForms, which is stored in the: formPropertyName
DynaActionForm dynaform = (DynaActionForm ) form;
ArrayList listOfFormDetails = (ArrayList) dynaform.get( formPropertyName );
// db bean array needed for all our service method calls
Class classOfDbBean = Class.forName( databaseBeanClass );
Object[] details = (Object[]) Array.newInstance( classOfDbBean, listOfFormDetails.size() );
// Create an instance of the service class.
Class serviceClass = Class.forName( crudMapping.getServiceName() );
Object service = serviceClass.newInstance();
// find the method that takes an array of data, and invoke it.
Object arguments[] = new Object[] { details };
Method svcMethod = serviceClass.getMethod(saveServiceMethodName, new Class[] { details.getClass()} );
Object result = svcMethod.invoke( service, arguments );
} // saveMultiRecordForm
Thanks for anyone who has made it this far!
Re: Code reduction for Action classes
Posted by Martin Gainty <mg...@hotmail.com>.
1)rewrite your save() logic to invoke form.getAction() and test on the returned parameter
if(form.getAction() == "save")
{
//do all your save logic here
return (mapping.findForward("save"));
}
//the last thing you need to do in your save method is to return the mapping for success as in
return (mapping.findForward("success"));
I cant speculate on any of the other classes as you havent displayed the code for those.
M-
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----- Original Message -----
From: "Givler, Eric" <eg...@state.pa.us>
To: "Struts Users Mailing List" <us...@struts.apache.org>
Sent: Wednesday, October 11, 2006 2:32 PM
Subject: Code reduction for Action classes
> I've been trying to get the hang of struts now for the past few months, and am wondering how people write "re-usable" base classes for Struts. If you have the time, I'd really appreciate your thoughts on this - bear with me, as it's a lot of reading:
>
> My actions tend to be "similar" but making them "reusable" seems to be eluding me.
>
> What I would like to have is a set of reusable actions that handle the following standard application features:
>
> 1. A wizard (multiple jsps, one form bean, data formatting, validation specific per page, with persistence when any navigation occurs, not just at the end). I've seen an example of an "at-the-end" wizard in the sample Chapter from Struts Recipes by George Franciscus and Danilo Gurovich.
> 2. A multi-record screen ( one jsp, array of items, formatting of data, validation w/ messages, and persistence)
>
> Are these already written, so I can save some time?
>
> So far, I've tried to write a re-usable piece of code for #2.
> Based on ideas in the ObjectSource Struts Survival Guide, Chapter 10:
>
> #1: I wrote my own mapping. Here are the properties:
>
> public class CRUDActionMapping extends ActionMapping{
> private String formType;
> private String formMultiRecordProperty;
> private String formDefConfig;
> private String databaseBeanClassName;
> private String saveServiceMethod;
> private String retrieveServiceMethod;
> private String serviceName;
>
> #2: My struts-config.xml for the action for this class is defined as:
>
> <action path="/cbdeqr_engcodehours"
> className="dep.ccdreporting.view.mappings.CRUDActionMapping"
> type="dep.ccdreporting.view.actions.cbp.CbdeqrEngCodeHoursAction"
> name="CbdeqrEngCodeHoursForm"
> input="/WEB-INF/jsp/cbp/cbdeqr_engcodehours.jsp"
> scope="session"
> validate="false"
> parameter="event_save=save,event_codehours=initializePage,
> event_reportInProgress=previous,event_countyHours=next,
> default=unspecified">
> <set-property property="cancellable" value="true"/>
> <set-property property="formType" value="MultiRecord"/>
> <set-property property="formMultiRecordProperty" value="codehours"/>
> <set-property property="formDefConfig" value="CbdeqrEngCodeHoursForm"/>
> <set-property property="databaseBeanClassName" value="dep.ccdreporting.model.vo.cbp.CbdeqrCodeHours"/>
> <set-property property="saveServiceMethod" value="saveCbdeqrCodeHours"/>
> <set-property property="retrieveServiceMethod" value="getEngCodeHours"/>
> <set-property property="serviceName" value="dep.ccdreporting.model.service.cbp.CBPDaoService"/>
> <forward name="hourspercounty" path="/cbdeqr_engcountyhours.do"/>
> <forward name="cbdeqr_main" path="/cbdeqr.do"/>
> <forward name="success" path="/WEB-INF/jsp/cbp/cbdeqr_engcodehours.jsp"/>
> </action>
>
> #3: The action class CbdeqrEngCodeHoursAction is reduced to two overridden methods (save and initializePage, due to calling a calculation) of a base class, and one method that gets the parameters to retrieve the data, which is:
>
> public HashMap getRetrieveServiceMethodParams( HttpServletRequest request ) {
> HttpSession session = request.getSession();
> UserBean userbean = (UserBean) session.getAttribute("usrbean");
> HashMap codeparams = new HashMap();
> codeparams.put("report_id" , userbean.getReport_id());
> return codeparams;
> } // getRetrieveServiceMethodParams
>
> #4: The base class handles the initialization of the page and the save. Here's the save() call so this message doesn't get too wordy:
>
> public ActionForward save(ActionMapping mapping,
> ActionForm form,
> HttpServletRequest request,
> HttpServletResponse response)
> throws Exception,
> ServletException
> {
> ActionForward fwd = mapping.getInputForward();
> if (isFormValid(mapping, form, request)) {
> if ( mapping instanceof CRUDActionMapping ) {
> CRUDActionMapping myMapping = (CRUDActionMapping) mapping;
> if (myMapping.getFormType().equalsIgnoreCase("MULTIRECORD")) {
> saveMultiRecordForm ( mapping, form, request );
> ...
>
> and the save code -- this is where I'm confused - is this a reasonable approach, or am I really missing the boat. Specifically: Should I be creating the service like this? Also, I really want the ability to log who is performing the service methods as well - i.e. request.getRemoteUser(), so do I have to pass this to the service method, or can I get it another way??
>
> public void saveMultiRecordForm ( ActionMapping mapping,
> ActionForm form,
> HttpServletRequest request )
> throws Exception
> {
> // get all the action-mapping properties
> CRUDActionMapping crudMapping = (CRUDActionMapping) mapping;
> String formPropertyName = crudMapping.getFormMultiRecordProperty();
> String formDefConfigName = crudMapping.getFormDefConfig();
> String databaseBeanClass = crudMapping.getDatabaseBeanClassName();
> String saveServiceMethodName = crudMapping.getSaveServiceMethod();
>
> // form-def returns an array of dynaActionForms, which is stored in the: formPropertyName
> DynaActionForm dynaform = (DynaActionForm ) form;
> ArrayList listOfFormDetails = (ArrayList) dynaform.get( formPropertyName );
>
> // db bean array needed for all our service method calls
> Class classOfDbBean = Class.forName( databaseBeanClass );
> Object[] details = (Object[]) Array.newInstance( classOfDbBean, listOfFormDetails.size() );
>
> // Create an instance of the service class.
> Class serviceClass = Class.forName( crudMapping.getServiceName() );
> Object service = serviceClass.newInstance();
>
> // find the method that takes an array of data, and invoke it.
> Object arguments[] = new Object[] { details };
> Method svcMethod = serviceClass.getMethod(saveServiceMethodName, new Class[] { details.getClass()} );
> Object result = svcMethod.invoke( service, arguments );
> } // saveMultiRecordForm
>
> Thanks for anyone who has made it this far!
>
>
>
Re: Code reduction for Action classes
Posted by Martin Gainty <mg...@hotmail.com>.
Eric
Take a look at the bottom save method
HTH
Martin --
> I've been trying to get the hang of struts now for the past few months, and am wondering how people write "re-usable" base classes for Struts. If you have the time, I'd really appreciate your thoughts on this - bear with me, as it's a lot of reading:
>
> My actions tend to be "similar" but making them "reusable" seems to be eluding me.
>
> What I would like to have is a set of reusable actions that handle the following standard application features:
>
> 1. A wizard (multiple jsps, one form bean, data formatting, validation specific per page, with persistence when any navigation occurs, not just at the end). I've seen an example of an "at-the-end" wizard in the sample Chapter from Struts Recipes by George Franciscus and Danilo Gurovich.
> 2. A multi-record screen ( one jsp, array of items, formatting of data, validation w/ messages, and persistence)
>
> Are these already written, so I can save some time?
>
> So far, I've tried to write a re-usable piece of code for #2.
> Based on ideas in the ObjectSource Struts Survival Guide, Chapter 10:
>
> #1: I wrote my own mapping. Here are the properties:
>
> public class CRUDActionMapping extends ActionMapping{
> private String formType;
> private String formMultiRecordProperty;
> private String formDefConfig;
> private String databaseBeanClassName;
> private String saveServiceMethod;
> private String retrieveServiceMethod;
> private String serviceName;
>
> #2: My struts-config.xml for the action for this class is defined as:
>
> <action path="/cbdeqr_engcodehours"
> className="dep.ccdreporting.view.mappings.CRUDActionMapping"
> type="dep.ccdreporting.view.actions.cbp.CbdeqrEngCodeHoursAction"
> name="CbdeqrEngCodeHoursForm"
> input="/WEB-INF/jsp/cbp/cbdeqr_engcodehours.jsp"
> scope="session"
> validate="false"
> parameter="event_save=save,event_codehours=initializePage,
> event_reportInProgress=previous,event_countyHours=next,
> default=unspecified">
> <set-property property="cancellable" value="true"/>
> <set-property property="formType" value="MultiRecord"/>
> <set-property property="formMultiRecordProperty" value="codehours"/>
> <set-property property="formDefConfig" value="CbdeqrEngCodeHoursForm"/>
> <set-property property="databaseBeanClassName" value="dep.ccdreporting.model.vo.cbp.CbdeqrCodeHours"/>
> <set-property property="saveServiceMethod" value="saveCbdeqrCodeHours"/>
> <set-property property="retrieveServiceMethod" value="getEngCodeHours"/>
> <set-property property="serviceName" value="dep.ccdreporting.model.service.cbp.CBPDaoService"/>
> <forward name="hourspercounty" path="/cbdeqr_engcountyhours.do"/>
> <forward name="cbdeqr_main" path="/cbdeqr.do"/>
> <forward name="success" path="/WEB-INF/jsp/cbp/cbdeqr_engcodehours.jsp"/>
> </action>
>
> #3: The action class CbdeqrEngCodeHoursAction is reduced to two overridden methods (save and initializePage, due to calling a calculation) of a base class, and one method that gets the parameters to retrieve the data, which is:
>
> public HashMap getRetrieveServiceMethodParams( HttpServletRequest request ) {
> HttpSession session = request.getSession();
> UserBean userbean = (UserBean) session.getAttribute("usrbean");
> HashMap codeparams = new HashMap();
> codeparams.put("report_id" , userbean.getReport_id());
> return codeparams;
> } // getRetrieveServiceMethodParams
>
> #4: The base class handles the initialization of the page and the save. Here's the save() call so this message doesn't get too wordy:
>
public ActionForward save(ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
throws Exception,
ServletException
{
/* ActionForward fwd = mapping.getInputForward(); */
/* if (isFormValid(mapping, form, request)) */
/*{ */
/* if ( mapping instanceof CRUDActionMapping ) */
/* { */
/* CRUDActionMapping myMapping = (CRUDActionMapping) mapping; */
/* if (myMapping.getFormType().equalsIgnoreCase("MULTIRECORD")) */
/* {*/
if(form.getAction() == 'save')
{
saveMultiRecordForm ( mapping, form, request );
return(mapping.findForward("save"));
}
//return back ActionForward defined for keyword success
return (mapping.findForward("success"));
}
> and the save code -- this is where I'm confused - is this a reasonable approach, or am I really missing the boat. Specifically: Should I be creating the service like this? Also, I really want the ability to log who is performing the service methods as well - i.e. request.getRemoteUser(), so do I have to pass this to the service method, or can I get it another way??
>
> public void saveMultiRecordForm ( ActionMapping mapping,
> ActionForm form,
> HttpServletRequest request )
> throws Exception
> {
> // get all the action-mapping properties
> CRUDActionMapping crudMapping = (CRUDActionMapping) mapping;
> String formPropertyName = crudMapping.getFormMultiRecordProperty();
> String formDefConfigName = crudMapping.getFormDefConfig();
> String databaseBeanClass = crudMapping.getDatabaseBeanClassName();
> String saveServiceMethodName = crudMapping.getSaveServiceMethod();
>
> // form-def returns an array of dynaActionForms, which is stored in the: formPropertyName
> DynaActionForm dynaform = (DynaActionForm ) form;
> ArrayList listOfFormDetails = (ArrayList) dynaform.get( formPropertyName );
>
> // db bean array needed for all our service method calls
> Class classOfDbBean = Class.forName( databaseBeanClass );
> Object[] details = (Object[]) Array.newInstance( classOfDbBean, listOfFormDetails.size() );
>
> // Create an instance of the service class.
> Class serviceClass = Class.forName( crudMapping.getServiceName() );
> Object service = serviceClass.newInstance();
>
> // find the method that takes an array of data, and invoke it.
> Object arguments[] = new Object[] { details };
> Method svcMethod = serviceClass.getMethod(saveServiceMethodName, new Class[] { details.getClass()} );
> Object result = svcMethod.invoke( service, arguments );
> } // saveMultiRecordForm
>
> Thanks for anyone who has made it this far!
>
>
>