Sling Models Default value returned for all properties

[Former Community Member]

I am experimenting with Sling Models. I followed Justin Edelson's advice about installing the API / Impl package from ACS, adding the instruction to the maven-bundle-plugin to generate the appropriate manifest header ... yadda, yadda

I defined an interface thus (note: the @Default values) :-

package com.aviva.aem.sling.models.telephonecontact; import javax.inject.Inject; import org.apache.sling.models.annotations.*; import org.apache.sling.api.resource.Resource; @Model(adaptables=Resource.class) public interface ITelephoneContact { @Inject @Optional @Default(values="Call Us") String getTitle(); @Inject @Optional @Default(values="TBA") String getContent(); @Inject @Optional @Default(values="For our joint protection all calls will be monitored.") String getMessage(); @Inject @Optional @Default(values="Calls to 0844 numbers are charged at 12p per minute. Calls to other numbers may vary.") String getCallCharges(); }

Packaged and installed my bundle then crufted up this JSPx to use it :-

<sling:findResources query="/jcr:root ... @sling:resourceType = 'avivapocs/components/telephone']" language="xpath" var="resources" /> <c:forEach var="telephoneResource" items="${resources}"> <sling:adaptTo adaptable="${resource}" adaptTo="com.aviva.aem.sling.models.telephonecontact.ITelephoneContact" var="model"/> <c:out value="${model.content}"/> </c:forEach>

So that you know, the findResources query DOES appear to find the FOUR telephone resources that are present in the location I used.

When I run this JSP I get :  TBA TBA TBA TBA (i.e. four default values)

If I change to ${model.title} I get : Call Us Call Us Call Us Call Us (default values again).

Looking in the JCR, there ARE different values for some of these, but none come thru.

I haven't mapped every property for the telephone resource in my interface yet (assumed I don't need to).

What am I doing wrong ??

Kind Regards

Fraser.

[Sham_HC]

Could you declare a name using @Named and verify. 

[justin_at_adobe · Accepted solution]

Hi,

There's a typo in your code.

<sling:adaptTo adaptable="${resource}" adaptTo="com.aviva.aem.sling.models.telephonecontact.ITelephoneContact" var="model"/>

should be

<sling:adaptTo adaptable="${telephoneResource}" adaptTo="com.aviva.aem.sling.models.telephonecontact.ITelephoneContact" var="model"/>

Justin

[Former Community Member]

Thx Justin, missing that was a bit embarassing !

Next problem is how to specify the 'openingHours' collection in the telephone model interface.

OpeningHours is a collection of Day,startTime and EndTime values where the Day is an enum (Monday, Tuesday, ... Sunday). This is what the dialog looks like :-

[img]slingModels2.jpg[/img]

and this is the content structure created :-

[img]slingModels1.jpg[/img]

But how do I model this on the interface. Maybe some sort of List ... but of what type ... do I need to create a second model interface with @Inject annotations ??

@Model(adaptables=Resource.class) public interface ITelephoneContact { ...     @Inject     List<IOpeningHours> openingHours @Model(adaptables=Resource.class) public interface IOpeningHours { @Inject @Optional @Named("Day") String getDay(); @Inject @Optional @Named("startTime") String getStartTime(); @Inject @Optional @Named("endTime") String getEndTime(); }

Does that make any sense or am I completely off track ?

Fraser.

[Former Community Member]

Good idea. Interface now looks like this (unfortunately same result though) :-

package com.aviva.aem.sling.models.telephonecontact; import javax.inject.Inject; import javax.inject.Named; import org.apache.sling.models.annotations.*; import org.apache.sling.api.resource.Resource; @Model(adaptables=Resource.class) public interface ITelephoneContact { @Inject @Optional @Default(values="Call Us")  @Named("title") String getTitle(); @Inject @Optional @Default(values="TBA") @Named("Content") String getContent(); @Inject @Optional @Default(values="For our joint protection all calls will be monitored.")  @Named("Message") String getMessage(); @Inject @Optional @Default(values="Calls to 0844 numbers are charged at 12p per minute. Calls to other numbers may vary.")  @Named("CallCharges") String getCallCharges(); }

I assume that the value of @Named should be the ACTUAL name of the JCR property ??

This is what that these are :-

[img]telephonecontacts.jpg[/img]

In the JSP I MUST use lower camelcase method names like this otherwise an exception occurs :-

${model.title} ${model.message} ${model.content} ${model.callCharges}

Fraser.

[justin_at_adobe]

Hi Fraser,

There's an open feature request at https://issues.apache.org/jira/browse/SLING-3516 which I think covers what you are describing. I haven't had a chance to review it fully, but it might be worth a look. Certainly something like what you are describing could be done with a custom injector.

Regards,

Justin

[Former Community Member]

Hey Justin,

still struggling with this, so any pointers much appreciated. Here's where I am.

I created a new model interface thus :-

package com.aviva.aem.sling.models.telephonecontact; import javax.inject.Inject; import javax.inject.Named; import org.apache.sling.models.annotations.*; import org.apache.sling.api.resource.Resource; @Model(adaptables=Resource.class) public interface IOpeningHours { @Inject @Optional @Named("day") String getDay(); @Inject @Optional @Named("startTime") String getStartTime(); @Inject @Optional @Named("endTime") String getEndTime(); }

and in the parent model I used :-

@Inject @Optional @Named("typeconfigs") @Source("child-resources") List<IOpeningHours> getOpeningHours();

I used @Named("typeconfigs") because this is the name of the JCR content node that contains the collection of Item_n (e.g Item_1, Item_2, etc.  - see picture above) and have tried with and without the named injector @Source("child-resources") but with the same results.

In the JSP if I use :-

<c:out value="Opening Hours: ${model.openingHours}"/>

I just get Opening Hours:  (i.e. no value comes through but no exception either - not surprising since getOpeningHours appears on the parent model interface I guess - if I use $model.XopeningHours obviously an exception occurs).

If in the JSP I use :-

<c:out value="Opening Hours: ${model.openingHours}"/> <c:out value="Day: ${model.openingHours.day}"/> <c:out value="Day: ${model.openingHours[0].day}"/> <c:out value="StartTime: ${model.openingHours[0].startTime}"/> <c:out value="EndTime: ${model.openingHours[0].endTime}"/> <c:out value="Opening Hours: ${fn:length(model.openingHours)}"/>

I get :   Opening Hours: Day: Day: StartTime: EndTime: Opening Hours: 0

So from that I conclude that the child resource is just not being found, and I've probably not got the model interfaces quite right too. Even if I use a non-existant property name like : ${model.openingHours[0].IDONTEXIST} I don't get an exception, which would re-enforce the fact that the child resource is just not mapped.

Documentation (particularly examples) is a bit scarce for Sling Models (at least beyond the simple ones). I could continue with trial an error but if anyone's got any further ideas or has some sample code, it would be most welcome.

Regards

Fraser.

[justin_at_adobe]

Hi Fraser,

Did you implement a custom injector to handle the List<?> method? Because, as I wrote above, that case currently isn't supported OOTB.

Happy to do whatever I can to update the documentation, but in this case, you appear to be trying to use a feature which doesn't exist. So the shouldn't be any surprise that it isn't documented. 

Justin

[Former Community Member]

Hi Justin,

No I didn't do that yet. I thought that might already be supported since in the Sling Models docs here it said :-

Lists and arrays are supported:

@Model(adaptables=Resource.class) public class MyModel { @Inject private List<Servlet> servlets; }

Also, when I read your earlier post I thought you were referring to the 'child-resources' injector, but as it turns out that doesn't appear to be needed.

I have had some further success with the OOTB functionality. Specifically I can reach each of the items below the typeconfigs, BUT, only by using their actual names (item_1, item2, etc..) so this JSP code now returns what is there in the JCR :-

<h3>Telephone resource : ${telephoneResourceStatus.count}</h3> <p> <c:out value="Day: ${model.typeConfigs.item1.day}"/> <c:out value="startTime: ${model.typeConfigs.item1.startTime}"/> <c:out value="endTime: ${model.typeConfigs.item1.endTime}"/> </p> <p> <c:out value="Day: ${model.typeConfigs.item2.day}"/> <c:out value="startTime: ${model.typeConfigs.item2.startTime}"/> <c:out value="endTime: ${model.typeConfigs.item2.endTime}"/> </p> <p> <c:out value="Day: ${model.typeConfigs.item3.day}"/>     <c:out value="startTime: ${model.typeConfigs.item3.startTime}"/>     <c:out value="endTime: ${model.typeConfigs.item3.endTime}"/> </p>

But as you say, the final problem to crack is to be able to return a List of these items regardless of their names.

Are there any docs on creating a custom injector ?

Regards

Fraser.