atom feed13 messages in org.apache.incubator.isis-usersRe: collection of similar types
FromSent OnAttachments
Stephen CameronNov 18, 2015 11:39 am 
Dan HaywoodNov 18, 2015 11:13 pm 
Stephen CameronNov 18, 2015 11:30 pm 
Stephen CameronNov 21, 2015 2:01 pm 
Dan HaywoodNov 22, 2015 6:23 am 
Vladimir Nišević Nov 23, 2015 5:16 am 
Dan HaywoodNov 23, 2015 5:25 am 
Vladimir Nišević Nov 23, 2015 7:19 am 
Dan HaywoodNov 23, 2015 7:30 am 
Vladimir Nišević Nov 24, 2015 7:11 am 
Dan HaywoodNov 24, 2015 7:14 am 
Dan HaywoodNov 26, 2015 7:11 am 
Vladimir NiševićNov 26, 2015 8:10 am 
Subject:Re: collection of similar types
From:Dan Haywood (
Date:Nov 26, 2015 7:11:45 am

Hi Vladimir,

thanks for pulling together that test case (though perhaps next time, just create a repo with just the simpleapp, rather than all of Isis?!?)

Anyway... the issue is a programming error, but easily made.

In some of your actions you are accessing fields directly, instead you should ALWAYS use the getters. This allows DataNucleus to perform its lazy loading of state.

For example, in

@Programmatic public boolean isFinishedOrInError() { // return status.isFinished() || status.isInError(); return getStatus().isFinished() || getStatus().isInError(); }

@Programmatic public boolean isProcessing() { // return this.status.isProcessing(); return this.getStatus().isProcessing(); }

@Programmatic public boolean isPlanned() { // return this.status.isPlanned(); return this.getStatus().isPlanned(); }


@Override protected List<String> checkForErrorsBeforeExecute() { List<String> errors = new ArrayList<>(); // if ( == null) if (getTechnology() == null) errors.add("No technology defined"); // if (this.dslamLocation == null) if (getDslamLocation() == null) errors.add("No DSLAM location defined"); return errors; }


@Override protected List<String> checkForErrorsBeforeExecute() { List<String> errors = new ArrayList<>(); // if (this.dslam == null) if (getDslam() == null) errors.add("No dslam defined"); // if (this.port == null) if (getPort() == null) errors.add("No port defined"); return errors; }

I suspect you've "got away with this" previously if you weren't using inheritance with each subtype in its own table. But for this example, they do, eg:

@javax.jdo.annotations.Inheritance(strategy = InheritanceStrategy.NEW_TABLE) /// this... public class StepSubtype1 extends Step {

Either way, always use getters. Moving actions into mixins (my new favorite feature of Isis) might be a way to help enforce this.

Cheers Dan

On 24 November 2015 at 15:11, Vladimir Nišević <> wrote:

Hi Dan, yes, that's exactly the problem.

I have adapted the simple-app trying to show my problem:

Meanwhile I understood that my integration test was wrong - I haven't used the wrapper. Now is my problem at least consistent through WebUI and Integration test, but I still have it.

To reproduce:

1. Start SampleAPP Webapp 2. Create new simple object 3. Execute action "Plan" on simple object (will add three steps of specific subtype). Two steps will have a specifc properties. 4. Exectute action "Execute" on simple object - status of first step change to processing, but since properties are not loaded, business logic prevent it from doing (my problem)


2015-11-23 16:30 GMT+01:00 Dan Haywood <>:

If I understand you correctly, sounds as if the query that you are using is only querying the supertype table, rather than doing left outer jobs for all subtypes.

But in guessing here... perhaps you could share some code that demonstrates the issue? On 23 Nov 2015 3:20 pm, "Vladimir Nišević" <> wrote:

Hi Dan, when I execute the action on order the steps instances are there, but the values of its properites are definitely empty - I've checked it thru debugging of webapp. When I open a view of single step, the values of that step are there.

I do not need to show additional values in a table, but have a problem with business logic when executing an action which uses a data on single step.

Any idea? Thanks, Vladimir

2015-11-23 14:25 GMT+01:00 Dan Haywood <>:

The objects are loaded, however the Wicket UI uses the compile time



the list to determine what columns to render.

I could imagine us allowing some sort of hint for the framework to be told to render the objects as per some other type (eg some "union interface" that combines all desired properties). But that would be a new feature, I think.

Dan. On 23 Nov 2015 1:16 pm, "Vladimir Nišević" <> wrote:

Hi, I have perhaps similar issue.

I have an object (Order) which contains a list of objects can be different type but all extend from the same superclass (Step). When I execute the action on order thru wicket UI, the properties of concrete classes StepType1 and StepType2 are not loaded. When I do the same thru Intergration Test, the values are there?

*class Order{* *.....* *//region > steps (collection)* *@Column(allowsNull = "true")* *@Persistent(mappedBy = "order", defaultFetchGroup = "true")* *private List<Step> steps = new ArrayList<>();*

*@Collection(editing = Editing.DISABLED)* *@CollectionLayout(render = RenderType.EAGERLY)* *public List<Step> getSteps() {* * return steps;* *}*

*public void setSteps(final List<Step> steps) {* * this.steps = steps;* *}* *....* *}*

*abstract class Step{* *....* *//region > order (property)* *@Persistent(defaultFetchGroup = "true")* *@Column(allowsNull = "false")* *private Order order;*

*@MemberOrder(name = "General", sequence = "1.1")* *@PropertyLayout(named = "Order", hidden = Where.PARENTED_TABLES)* *public Order getOrder() {* * return order;* *}*

*public void setOrder(final Order order) {* * this.order = order;* *}* *.....* *}*

*class StepType1 extends Step{* *//region > ipAdresse (property)* *private String ipAdresse;*

*@MemberOrder(sequence = "1")* *@javax.jdo.annotations.Column(allowsNull = "true")* *public String getIpAdresse() {* * return ipAdresse;* *}*

*public void setIpAdresse(final String ipAdresse) {* * this.ipAdresse = ipAdresse;* *}* *....* *} *

*class StepType2 extends Step{* *....* *private String dslam;*

*@MemberOrder(name = "Output", sequence = "1.0")* *@PropertyLayout(named = "DSLAM")* *@javax.jdo.annotations.Column(allowsNull = "true")* *public String getDslam() {* * return dslam;* *}*

*public void setDslam(final String dslamId) {* * this.dslam = dslamId;* *}* *.....* *} *

2015-11-22 15:23 GMT+01:00 Dan Haywood <


On 21 November 2015 at 22:01, Stephen Cameron <> wrote:

Actually, it already does have the behaviour that I wanted.

OK, that's good to hear.

I'll try individual icons for the subtypes and see if it uses



of the one for the base-type.

It should do. In the todoapp we use the similar cssClass() to

return a

CSS class name per instance, and then use application.css to



different values. This is how individual rows within a table



todo items "crossed-off", ie with a line through the centre.



also vary on a case by case basis.