Internationalization enhancements for Java 9 include enabling of CLDR Locale Data by Default.
There are four distinct sources for locale data identified by using the below keywords:
In Java 8 and previous versions, JRE is default locale data. Java 9 sets CLDR as the highest priority by default. We select a locale data source in preferred order by using java.locale.providers system property. If a provider has failed to request locale data, the next provider can be processed.
If we don’t set the property, the default behavior is:
To make compatible with Java 8, keep COMPAT ahead of CLDR.