public static CompositePropertySource configureEnvironmentPropertySources(final ConfigurableEnvironment environment) {
        val nativePropertySources = new CompositePropertySource("casNativeCompositeSource");
        val propertySources = environment.getPropertySources();
        FunctionUtils.doIfNotNull(propertySources.get("commandLineArgs"), nativePropertySources::addFirstPropertySource);
        FunctionUtils.doIfNotNull(propertySources.get("systemProperties"), nativePropertySources::addPropertySource);
        FunctionUtils.doIfNotNull(propertySources.get("systemEnvironment"), nativePropertySources::addPropertySource);
        return nativePropertySources;
    }
Configure environment property sources property source.

@param environment the environment
@return the property source
core/cas-server-core-configuration-api/src/main/java/org/apereo/cas/configuration/CasConfigurationPropertiesEnvironmentManager.java