public List<String> validate() {
        LOGGER.info("Validating CAS property sources and configuration for active profiles [{}]. Please wait...",
            Arrays.toString(applicationContext.getEnvironment().getActiveProfiles()));
        val validationResults = validateCasConfiguration();
        if (validationResults.isEmpty()) {
            LOGGER.info("Validated CAS property sources and configuration successfully.");
        } else {
            var message = String.join("\n", validationResults);
            message += "\n\nListed settings above are no longer recognized by CAS "
                       + CasVersion.getVersion() + ". They may have been renamed, removed, or relocated "
                       + "to a new namespace in the CAS configuration schema. CAS will ignore such settings to proceed with its normal initialization sequence. "
                       + "Please consult the CAS documentation to review and adjust each setting to find an alternative or remove the "
                       + "definition from the property source. Failure to do so puts the server stability in danger and complicates future upgrades.\n";
            LOGGER.error(message);
        }
        return validationResults;
    }
Validate the cas configuration properties
from property sources found in the application
context and report back results..

@return the list
core/cas-server-core-configuration-api/src/main/java/org/apereo/cas/configuration/CasConfigurationPropertiesValidator.java