Re: [jetty-users] how does org.eclipse.jetty.client.HttpClient or org.ec

[Simone Bordet <sbordet@xxxxxxxxxxx>]

Hi,

On Fri, Feb 21, 2020 at 10:57 AM Cao, William (NSB - CN/Qingdao)
<william.cao@xxxxxxxxxxxxxxx> wrote:
>
> Hi Simone，
>
> Many thanks for your quick help.
> I plan to change code as below. Could you please help check if it is correct?
>
> ...
>              HttpClient client = new HttpClient(clientTLSFactory);
>             client.setBindAddress(new InetSocketAddress("10.9.101.100", 0)); //local IP
>
>             client.setSocketAddressResolver(new SocketAddressResolver() {
>                   @Override
>                   public void resolve(String host, int port, Promise<List<InetSocketAddress>> promise) {
>                       try
>                       {
>                           //above host is the FQDN of remote https server after SRV record resolving,
>                           //in this example, it is "www.eclipse.org"
>                           //DO DNS A/AAAA lookup for above host to get a list of IPs
>                           //select one IP from above IPs list according to some rule,
>                           //    and assign this IP to host
>                           host = <the selected IP>; //e.g, 198.41.30.198
>
>                           InetAddress[] addresses = InetAddress.getAllByName(host);
>
>                           List<InetSocketAddress> result = new ArrayList<>(addresses.length);
>                           for (InetAddress address : addresses)
>                               result.add(new InetSocketAddress(address, port));
>
>                           if (result.isEmpty())
>                               promise.failed(new UnknownHostException());
>                           else
>                               promise.succeeded(result);
>                       }
>                       catch (Throwable x)
>                       {
>                           promise.failed(x);
>                       }
>                   }
>               });
>
>             Request httpsreq = client.newRequest("https://www.eclipse.org/jetty/";)
>                                           .method(org.eclipse.jetty.http.HttpMethod.POST);
>
>             httpsreq.header(headerName, headerValue);
>             httpsreq.content(new BytesContentProvider("Hello Jetty"), "application/json");
>             httpsreq.send(new Response.Listener.Adapter() { ......});

More or less correct.

Since you have just one numeric address (the selected IP), there is no
point in calling getAllByteName() as getByName() is sufficient.
And because it's already a numeric address, you will not incur in
blocking DNS lookup by calling getByName().
Again because it's just one address, you can use Collections.singletonList().
Promise completion is correct.

-- 
Simone Bordet
----
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