java.lang.UnsupportedOperationException: getRowData(String rowKey) must be implemented when basic rowKey algorithm is not used

Question

I have upgraded PrimeFaces from 5.1 final to 5.2 final (the Community Release). I have a which is lazily loaded as follows (a minimal exampl

Answer 1

As mentioned in this link pointing to the PrimeFaces Community Forum,

We changed that part by design cause the rowKey attribute handling with a LazyDataModel is not correct.

Those two methods getRowKey() and getRowData() need to be implemented in the associated managed bean whenever LazyDataModel<T> is used as shown in the question.

From PrimeFaces User Guide (PDF) - (5.1 (page 164) and 5.2 (page 166)) :

Lazy Loading is an approach to deal with huge datasets efficiently, regular ajax based pagination works by rendering only a particular page but still requires all data to be loaded into memory. Lazy loading datatable renders a particular page similarly but also only loads the page data into memory not the whole dataset. In order to implement this, you’d need to bind a org.primefaces.model.LazyDataModel as the value and implement load method and enable lazy option. Also it is required to implement getRowData and getRowKey if you have selection enabled.

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The attribute rowKey may be used, when lazy is disabled -- is set to false (default) and row selection is enabled.

From PrimeFaces User Guide (PDF) - (5.1 (page 159) and 5.2 (page 161)) :

RowKey should a unique identifier from your data model and used by datatable to find the selected rows. You can either define this key by using the rowKey attribute or by binding a data model which implements org.primefaces.model.SelectableDataModel.

Such as,

<p:dataTable var="car"
             value="#{carBean.cars}"
             selection="#{carBean.selectedCars}"
             rowKey="#{car.id}">

    <p:column selectionMode="multiple"/>
    <!--columns-->
</p:dataTable>