Why does ListView JSP tag serialize entire data object?

[Jane]

The ListViewTag class serialises the entire data object, even if those fields aren't used in the ListView.  I'm using a Hibernate entity which uses a list of objects from a many-to-many relationship and I only want to retrieve these when I need them.  When the Serializer class tries to serialise the  object then Hibernate tries to populate the list but it can't because there is no database session open.

Is there any way fields can be ignored by the com.kendoui.taglib.json.Serializer?

See stack trace:

org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.syngenta.combichem.model.CcwEnumeration.buildingBlocks, could not initialize proxy - no Session
    org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:575)
    org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:214)
    org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:554)
    org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:142)
    org.hibernate.collection.internal.PersistentSet.iterator(PersistentSet.java:180)
    com.kendoui.taglib.json.Serializer.serializeIterable(Serializer.java:171)
    com.kendoui.taglib.json.Serializer.serialize(Serializer.java:109)
    com.kendoui.taglib.json.Serializer.serializeMap(Serializer.java:158)
    com.kendoui.taglib.json.Serializer.serialize(Serializer.java:121)
    com.kendoui.taglib.json.Serializer.serializeIterable(Serializer.java:174)
    com.kendoui.taglib.json.Serializer.serialize(Serializer.java:109)
    com.kendoui.taglib.json.Serializer.serializeMap(Serializer.java:158)
    com.kendoui.taglib.json.Serializer.serialize(Serializer.java:113)
    com.kendoui.taglib.json.Serializer.serializeMap(Serializer.java:158)
    com.kendoui.taglib.json.Serializer.serialize(Serializer.java:111)
    com.kendoui.taglib.WidgetTag.script(WidgetTag.java:101)
    com.kendoui.taglib.WidgetTag.doEndTag(WidgetTag.java:61)
    com.kendoui.taglib.ListViewTag.doEndTag(ListViewTag.java:82)

[Alex Hajigeorgieva]

Hi Jane,

Unfortunately, the Serializer class does not afford such functionality of skipping properties. You can check the source code which serialises at:

https://github.com/telerik/kendo-ui-core/blob/a2c7ec547302c4741103f1f1bb034b57eb201f45/wrappers/java/kendo-taglib/src/main/java/com/kendoui/taglib/json/Serializer.java#L97

One way to go around this could be to create a ViewModel (or in your case a couple of ViewModels) which includes the required properties only.

I hope this helps.

Kind Regards,
Alex Hajigeorgieva
Telerik by Progress

[Jane]

Thanks Alex, we found another workaround.  The Jackson JSON library has an annotation which can be used  so that it's deserializer ignores missing fields.  A similar annotation would be useful for the Kendo Serializer to ignore certain fields. 

[Alex Hajigeorgieva]

Hello Jane,

Thank you very much for getting back to share your solution here.

It seems like it would be a useful enhancement of the JSP wrappers Serializer.

We care what our clients have to say and record the popularity of new ideas in our UserVoice portal. Ideas which get upvoted the most are reviewed by the team and prioritised for future development.

The Kendo UI JSP ideas section is available at:

http://kendoui-feedback.telerik.com/forums/127393-kendo-ui-feedback/category/63709-jsp-wrappers

Kind Regards,
Alex Hajigeorgieva
Telerik by Progress