private static int randomClientPort() {
        return ThreadLocalRandom.current().nextInt(32768, 65536);
    }
Sets the local socket address of the connection. If not set, it is auto-generated with the localhost
IP address (e.g. {@code "127.0.0.1"} or {@code "::1"}).
core/src/main/java/com/linecorp/armeria/common/AbstractRequestContextBuilder.java