public ServerBuilder clientAddressSources(ClientAddressSource... clientAddressSources) {
        this.clientAddressSources = ImmutableList.copyOf(
                requireNonNull(clientAddressSources, "clientAddressSources"));
        return this;
    }
Sets a list of {@link ClientAddressSource}s which are used to determine where to look for the
client address, in the order of preference. {@code Forwarded} header, {@code X-Forwarded-For} header
and the source address of a PROXY protocol header will be used by default.
core/src/main/java/com/linecorp/armeria/server/ServerBuilder.java