Composite Component with f:convertNumber won't work

问题

I made a JSF composite component which uses f:convertNumber. However, it cannot convert value. How is this caused and how can I solve it?

currency.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:composite="http://java.sun.com/jsf/composite"
    xmlns:f="http://java.sun.com/jsf/core">

    <composite:interface>
    </composite:interface>

    <composite:implementation>
        <f:convertNumber pattern="#,###" currencyCode="\\"/> 
    </composite:implementation>
</html>

index.xhtml

...

<h:outputText value="10000000">
  <mycomp:currency />
</h:outputText>

...

result

10000000

回答1:

This will indeed not work.

Composite components are interpreted as UI components. The <f:convertNumber>, however, is a taghandler, not an UI component. Basically, it will get applied on the composite itself (and render as useless), not on the target component as you intented.

You've at least two options:

Move <h:outputText> into the composite too,

<composite:interface>
    <composite:attribute name="value" />
</composite:interface>
<composite:implementation>
    <h:outputText value="#{cc.attrs.value}">
        <f:convertNumber pattern="#,###" currencyCode="\\" />
    </h:outputText>
</composite:implementation>

so you can ultimately use it as below.

<mycomp:currency value="10000000" />

Subclass NumberConverter with default values set in constructor and use it instead.

@FacesConverter("defaultCurrencyConverter")
public class DefaultCurrencyConverter extends NumberConverter {

    public DefaultCurrencyConverter() {
        setPattern("#,###");
        setCurrencyCode("\\");
    }

}

<h:outputText value="10000000" converter="defaultCurrencyConverter" />

When you register this converter in a tagfile as described here Creating custom tag for Converter with attributes,

<tag>
    <tag-name>currency</tag-name>
    <converter>
        <converter-id>defaultCurrencyConverter</converter-id>
    </converter>
</tag>

then you can ultimately use it as intented.

<h:outputText value="10000000">
    <mycomp:currency />
</h:outputText>

Composite Component with f:convertNumber won't work

问题

回答1:

See also: