public Configuration getConfiguration(LoggerContext, String, List<URI>);

private Configuration getConfiguration(@Nullable URI requestedLocation) {
    final LoggerContext ctx = getLoggerContext();
    final ConfigurationFactory factory = ConfigurationFactory.getInstance();

    final URI main = resolveMainConfigLocation(requestedLocation, ctx, factory);
	final List<URI> overrides = getOverrides();

    // For version `2.25.x` or earlier the existing `mergeConfigurations` method can be used
    final List<URI> locations = new ArrayList<>(overrides.size() + 1);
    locations.add(main);
    locations.addAll(overrides);

    return factory.getConfiguration(ctx, null, locations);
}

private URI resolveMainConfigLocation(@Nullable URI requestedLocation,
                                      LoggerContext ctx,
                                      ConfigurationFactory factory) {
    // 1) Explicit override from caller
    if (requestedLocation != null) {
        return requestedLocation;
    }

    // 2) Current configuration (if it has a source URI)
    final Configuration current = ctx.getConfiguration();
    final URI currentUri = current.getConfigurationSource().getURI();
    if (currentUri != null) {
        return currentUri;
    }

    // 3) Named "-spring" configuration (if available)
    final Configuration springCfg = factory.getConfiguration(ctx, "-spring", null);
    if (springCfg != null) {
        final URI springUri = springCfg.getConfigurationSource().getURI();
        if (springUri != null) {
            return springUri;
        }
    }

    // 4) Fallback default
    return URI.create("classpath:org/springframework/boot/logging/log4j2/log4j2.xml");
}

// Replaced by checking the URI of the current Log4j Core configuration
// No need to know the details of which URI's are checked
protected @Nullable String getSelfInitializationConfig();
protected String[] getStandardConfigLocations();
// Replaced by `getConfiguration(ctx, "-spring", null)`
protected @Nullable String getSpringInitializationConfig();
protected String[] getSpringConfigLocations();
// 
protected void loadConfiguration(LoggingInitializationContext initializationContext, String location, @Nullable LogFile logFile);