default String getAppId() {
        return getAsString(APP_ID).orElseThrow(
            () -> new SpeedmentConfigException(
                "All applications must have an 'appId' property."
            )
        );
    }
Returns the unique id for this application. This is usually generated on
application launch. The value should be formatted as a
{@link java.util.UUID}.

@return  the app id
runtime-parent/runtime-config/src/main/java/com/speedment/runtime/config/Project.java