public Class<? extends ServerDomainSocketChannel> domainServerChannelType() {
        return provider.domainServerChannelType();
    }
Returns the {@link ServerDomainSocketChannel} class that is available for this transport type.

@throws IllegalStateException if this {@link TransportType} is not currently available or
                              doesn't support Unix domain sockets.
core/src/main/java/com/linecorp/armeria/common/util/TransportType.java