// Implement the MiniAppProxy API
public class YourMiniAppProxyImpl extends BaseMiniAppProxyImpl {
    @Override
    public Locale getLocale() {
        // Return the language you want to set
        return Locale.SIMPLIFIED_CHINESE; // Simplified Chinese
        // or return Locale.US; // English
        // or return new Locale("ar", "SA"); // Arabic
        // or return new Locale("in", "ID"); // Indonesian
        // or return Locale.FRANCE; // French
    }
}