Exporter breaks on complex value expressions

[rootkit007]

If my dataTable contains value expressions like:

<p:column>
    <h:outputText value="#{myBean.getData(var.property)}">
    </h:outputText>
</p:column>

it will render fine on the screen but throw 'Property getData not found on myBean' exception when exporting. This is apparently caused by this code in Exporter class:

//Try to guess else { ValueExpression expr = component.getValueExpression("value"); if (expr != null) { Class<?> valueType = expr.getType(context.getELContext()); if (valueType != null) { Converter converterForType = context.getApplication().createConverter(valueType);

                    if (converterForType != null)
                        return converterForType.getAsString(context, component, value);
                }
            }
        }

on line expr.getType

[ova2]

Assigned to Sudheer.

[gustavocampos]

Same problem here for any expression containing a method or something that is not a get/set property. I tried setting style="display: none;", but the outputText is read even if it's not shown.

Maybe data that is not visible on screen shouldn't be exported.

[sudheerj]

Could you please post your datatable and exporter code

[gustavocampos]

I'm using the default ExcelExporter (xlsx) and traced the problem to the same line as rootkit007, it happens when expr.getType() is called for a datatable component like:

h:outputText value="#{fundReturns.getFundClassName(fundReturns.navReturns[date][eCounter.index].idtLinkedTo)}"

The error happens when the code tries to get the expected type to find a converter, because getType is for properties and not for methods.

[rootkit007]

I remember seeing the same discussion about PF dataExporter component. One of proposed fixes was to change that call to getExpectedType(), but I havent tried this myself

[gustavocampos]

I have just tried and it works, but it returned me an Object, even with the return type of my method being a String, so I don't know whether it will break other things or not.

[ova2]

Hi,

We use getType() in other components too. The correct method is in ComponentsUtils.java. Sudheer, please use the method getConverter() from there. It works as follows:

public static Converter getConverter(final FacesContext fc, final UIComponent component) {
    if (!(component instanceof EditableValueHolder)) {
        return null;
    }

    Converter converter = ((EditableValueHolder) component).getConverter();
    if (converter != null) {
        return converter;
    }

    ValueExpression valueExpression = component.getValueExpression("value");
    if (valueExpression == null) {
        return null;
    }

    Class<?> converterType = valueExpression.getType(fc.getELContext());
    if (converterType == null || converterType == String.class || converterType == Object.class) {
        // no conversion is needed
        return null;
    }

    return fc.getApplication().createConverter(converterType);
}

[gustavocampos]

It works for me.

[ova2]

Do you mean my code above with "it works for me"?

[gustavocampos]

Yes, I called getConverter() from ComponentUtils.java

[ova2]

Good to hear. This is how it works in JSF impl. too. PF didn't have these lines

if (converterType == null || converterType == String.class || converterType == Object.class) {
    // no conversion is needed
    return null;
}

and it was the problem. Don't know about the current PF version.

So, Sudheer, please fix the Exporter asap :-)

[tandraschko]

The String type check isn't right in all cases because user can have string converter for trimming etc. Please just call our ComponentUtils#getConverter, i will later change it to PF ComponentUtils

[ova2]

Set for 0.7.1

[sudheerj]

Fixed.