Using parametric Resource Bundle keys in EL expressions

Sometimes we have the need of defining parametric keys in a resource bundle file, to make the EL expressions in our ADF pages/fragments more readable and maintainable.

For this purpose, ADF provides EL functions which support both positional and named parameters.

• af:formatString : for formatting a string with a positional parameter. 
• af:formatString2 : for formatting a string with two positional parameters.
• af:formatString3 : for formatting a string with three positional parameters.
• af:formatString4 : for formatting a string with four positional parameters. 
• af:formatNamed : for formatting a string with a named parameter. 
• af:formatNamed2 : formatting a string with two named parameters. 
• af:formatNamed3 : for formatting a string with three named parameters. 
• af:formatNamed4 : for formatting a string with four named parameters. 

If we use named parameters in our resource bundles:

SCAN_DURATION_VALUE={HOURS} hours, {MINS} minutes 

We can use the formatNamed functions:

<af:outputText value="#{af:formatNamed2(myBundle.SCAN_DURATION_VALUE,
                                                 'HOURS', varHours, 
                                                 'MINS', varMins)}"/>

If we use positional parameters instead:

 
TASK_CURRENT_STEP=Currently executing step {0} of {1}

Then we can use the formatString functions:

<af:outputText value="#{af:format2(myBundle.TASK_CURRENT_STEP, var1, var2)}"/>

In alternative, we can use the JSF outputformat component, which uses a positional approach:

  
<h:outputFormat value="#{myBundle.TASK_CURRENT_STEP}" id="of2">
     <f:param value="#{pageFlowScope.var1}" id="p1"/>
     <f:param value="#{pageFlowScope.var2}" id="p3"/>
</h:outputFormat>