}
        return UNASSIGNED
    }

    void requireHttpPort(int occurrence) {
        if (httpPort == UNASSIGNED) {
            if (parseHttpPort(occurrence) == UNASSIGNED) {
                throw new IllegalStateException("Could not parse Play http port from gradle output!")
            }
        }
    }

    void requireHttpPort() {
        requireHttpPort(0)
    }

    void initialize(GradleHandle gradle) {