httpserver does not close connections when RejectedExecutionException occurs

[Chris Hegarty]

Hi Yuji,

On 05/11/16 18:27, KUBOTA Yuji wrote:
> Hi all,
>
> com.sun.net.httpserver in jdk9 does not catch
> RejectedExecutionException and it does not close connections. We must
> catch this exception to close a socket.
>
> Please review the following patch and reproduce steps.
> If you agree with that this is an issue of jdk9, I create a new issue
> on JBS. (I'm author)

Please file an issue for this.

> * patch
> diff --git a/src/jdk.httpserver/share/classes/sun/net/httpserver/ServerImpl.java
> b/src/jdk.httpserver/share/classes/sun/net/httpserver/ServerImpl.java
> --- a/src/jdk.httpserver/share/classes/sun/net/httpserver/ServerImpl.java
> +++ b/src/jdk.httpserver/share/classes/sun/net/httpserver/ServerImpl.java
> @@ -442,10 +442,13 @@
>                  logger.log (Level.TRACE, "Dispatcher (4)", e1);
>                  closeConnection(conn);
>              } catch (IOException e) {
>                  logger.log (Level.TRACE, "Dispatcher (5)", e);
>                  closeConnection(conn);
> +            } catch (RejectedExecutionException e) {
> +                logger.log (Level.TRACE, "Dispatcher (9)", e);
> +                closeConnection(conn);
>              }
>          }
>      }
> _
>      static boolean debug = ServerConfig.debugEnabled ();

This looks ok. I wonder if some of these exceptions could be refactored
into a catch clause with several exception types?

-Chris.


> * steps to reproduce
>  1. java -Djava.util.logging.config.file=logging.properties SmallHttpServer
>  2. post tcp connections by curl or other ways
>      e.g.: while true; do curl -XPOST --noproxy 127.0.0.1
> http://127.0.0.1:8080/; done
>  3. wait RejectedExecutionException occurs as below and then
> SmallHttpServer stops by this issue.
> ----
> Nov 05, 2016 12:01:48 PM sun.net.httpserver.ServerImpl$Dispatcher run
> FINER: Dispatcher (7)
> java.util.concurrent.RejectedExecutionException: Task
> sun.net.httpserver.ServerImpl$Exchange at 37b50d9e rejected from
> java.util.concurrent.ThreadPoolExecutor at 1b3178d4[Running, pool size =
> 1, active threads = 0, queued tasks = 0, completed tasks = 7168]
>         at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(java.base/ThreadPoolExecutor.java:2076)
>         at java.util.concurrent.ThreadPoolExecutor.reject(java.base/ThreadPoolExecutor.java:842)
>         at java.util.concurrent.ThreadPoolExecutor.execute(java.base/ThreadPoolExecutor.java:1388)
>         at sun.net.httpserver.ServerImpl$Dispatcher.handle(jdk.httpserver/ServerImpl.java:440)
>         at sun.net.httpserver.ServerImpl$Dispatcher.run(jdk.httpserver/ServerImpl.java:405)
>         at java.lang.Thread.run(java.base/Thread.java:844)
> (SmallHttpServer is stopping by not closing socket)
> ----
>
> *logging.properties
> handlers = java.util.logging.ConsoleHandler
> com.sun.net.httpserver.level = FINEST
> java.util.logging.ConsoleHandler.level = FINEST
> java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter
>
> * SmallHttpServer.java
> import com.sun.net.httpserver.HttpExchange;
> import com.sun.net.httpserver.HttpHandler;
> import com.sun.net.httpserver.HttpServer;
>
> import java.net.InetSocketAddress;
> import java.util.Scanner;
> import java.util.concurrent.LinkedBlockingQueue;
> import java.util.concurrent.ThreadPoolExecutor;
> import java.util.concurrent.TimeUnit;
>
> public class SmallHttpServer {
>
>     public static void main(String[] args) throws Exception {
>         int POOL_SIZE = 1;
>         String HOST = args.length < 1 ? "127.0.0.1" : args[0];
>         int PORT = args.length < 2 ? 8080 : Integer.valueOf(args[1]);
>
>         // Setup a minimum thread pool to rise
> RejectExecutionException in httpserver
>         ThreadPoolExecutor miniHttpPoolExecutor
>                 = new ThreadPoolExecutor(POOL_SIZE, POOL_SIZE, 0L,
> TimeUnit.MICROSECONDS,
>                         new LinkedBlockingQueue<>(1), (Runnable r) -> {
>                             return new Thread(r);
>                         });
>         HttpServer httpServer = HttpServer.create(new
> InetSocketAddress(HOST, PORT), 0);
>         httpServer.setExecutor(miniHttpPoolExecutor);
>
>         HttpHandler res200handler = (HttpExchange exchange) -> {
>             exchange.sendResponseHeaders(200, 0);
>             exchange.close();
>         };
>         httpServer.createContext("/", res200handler);
>
>         httpServer.start();
>         // Wait stdin to exit
>         Scanner in = new Scanner(System.in);
>         while (in.hasNext()) {
>             System.out.println(in.nextLine());
>         }
>         httpServer.stop(0);
>         miniHttpPoolExecutor.shutdownNow();
>     }
> }
>
>
> Thanks,
> Yuji
>