How does EL empty operator work in JSF?

Question

In JSF an component can be rendered or not using the EL empty operator

rendered=\"#{not empty myBean.myList}\"

As I\'ve understood the ope

Answer 1

Using BalusC's suggestion of implementing Collection i can now hide my primefaces p:dataTable using not empty operator on my dataModel that extends javax.faces.model.ListDataModel

Code sample:

import java.io.Serializable;
import java.util.Collection;
import java.util.List;
import javax.faces.model.ListDataModel;
import org.primefaces.model.SelectableDataModel;

public class EntityDataModel extends ListDataModel implements
        Collection, SelectableDataModel, Serializable {

    public EntityDataModel(List data) { super(data); }

    @Override
    public Entity getRowData(String rowKey) {
        // In a real app, a more efficient way like a query by rowKey should be
        // implemented to deal with huge data
        List entitys = (List) getWrappedData();
        for (Entity entity : entitys) {
            if (Integer.toString(entity.getId()).equals(rowKey)) return entity;
        }
        return null;
    }

    @Override
    public Object getRowKey(Entity entity) {
        return entity.getId();
    }

    @Override
    public boolean isEmpty() {
        List entity = (List) getWrappedData();
        return (entity == null) || entity.isEmpty();
    }
    // ... other not implemented methods of Collection...
}