public Application getForVersion(ApplicationId applicationId, Optional<Version> vespaVersion, Instant now) throws VersionDoesNotExistException {
        return applicationVersions(applicationId).getForVersionOrLatest(vespaVersion, now);
    }
Retrieve the Application corresponding to this application id and specified vespa version.

@return the matching application, or null if none matches
configserver/src/main/java/com/yahoo/vespa/config/server/application/ApplicationMapper.java