ResourceBundle properties not resolved since WildFly 14 (10-13 work fine)

[linuxexpert]

I am developing an application with JSF 2.2 and running it on WildFly. With WildFly 14.0.1, my i18n properties are not resolved properly. They are all shown as "???somekey???". The very same source code works fine on WildFly 10, 11, 12, and 13 though. Since the very same code stopped working with WildFly 14, it should be something within this version. Any idea what the problem could be?

My properties file is defined within faces-config.xml:

<?xml version="1.0" encoding="UTF-8"?>

<faces-config xmlns="http://xmlns.jcp.org/xml/ns/javaee"

    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-facesconfig_2_2.xsd"

    version="2.2">

  <application>

    <locale-config>

      <default-locale>en</default-locale>

    </locale-config>

    <resource-bundle>

      <base-name>messages</base-name>

      <var>msg</var>

    </resource-bundle>

  </application>

</faces-config>

[linuxexpert]

Well, I found the solution and I'm asking myself if the different behaviour in WildFly 14 is by design:

My i18n properties file was called messages.properties, which worked fine up to WildFly 13. With 14 it only works if I rename the file to messages_en.properties.

Can anyone clarify what the right behaviour would be here?

[jaikiran]

I suspect that's a bug. But I haven't checked the latest specifications to be sure. However, given that it was working in previous versions of WildFly, could you create a JIRA here - JBoss Issue Tracker  and provide the necessary details, including a link to this thread? Someone from the WildFly team could then look into it.

[brian.stansberry]

This is due to a flaw in Yasson: Consider renaming messages.properties · Issue #62 · eclipse-ee4j/yasson · GitHub

It has been fixed in master via an upgrade of Yasson. See [WFLY-11202] Default ResourceBundle fails to load - JBoss Issue Tracker