private Path installApplicationPath() {
        Optional<String> variable = optionalInstallVariable(APPLICATION_LOCATION_INSTALL_VARIABLE);

        return variable.map(Paths::get)
                .orElseThrow(() -> new IllegalStateException("Environment variable not set: " + APPLICATION_LOCATION_INSTALL_VARIABLE));
    }
@author Tony Vaagenes
@author gjoranv
@author ollivir
standalone-container/src/main/java/com/yahoo/container/standalone/StandaloneContainerApplication.java