486930 - Selector does not correctly handle rejected execution exception

Improved comments and unit test

jetty-io/src/test/java/org/eclipse/jetty/io/SelectChannelEndPointTest.java

@@ -777,11 +777,45 @@ public class SelectChannelEndPointTest
             }.start();
         }
 
+        // unblock the handling
         latch.countDown();
+        
+        // wait for all clients to complete or fail
         closed.await();
+        
+        // assert some clients must have been rejected
         Assert.assertThat(rejections.get(),Matchers.greaterThan(0));
+        // but not all of them
         Assert.assertThat(rejections.get(),Matchers.lessThan(10));
+        // none should have timed out
         Assert.assertThat(timeout.get(),Matchers.equalTo(0));
-        Assert.assertThat(echoed.get(),Matchers.equalTo(10-rejections.get()));        
+        // and the rest should have worked
+        Assert.assertThat(echoed.get(),Matchers.equalTo(10-rejections.get())); 
+        
+        // and the selector is still working for new requests
+        try(Socket client = newClient();)
+        {
+            client.setSoTimeout(5000);
+
+            SocketChannel server = _connector.accept();
+            server.configureBlocking(false);
+
+            _manager.accept(server);
+
+            // Write client to server
+            client.getOutputStream().write("HelloWorld".getBytes(StandardCharsets.UTF_8));
+            client.getOutputStream().flush();
+            client.shutdownOutput();
+
+            // Verify echo server to client
+            for (char c : "HelloWorld".toCharArray())
+            {
+                int b = client.getInputStream().read();
+                assertTrue(b > 0);
+                assertEquals(c, (char)b);
+            }
+            assertEquals(-1,client.getInputStream().read());
+        }
+        
     }
 }

jetty-util/src/main/java/org/eclipse/jetty/util/thread/strategy/ExecuteProduceConsume.java

@@ -147,6 +147,7 @@ public class ExecuteProduceConsume implements ExecutionStrategy, Runnable
                 }
                 catch(Throwable e)
                 {
+                    // just warn if lowresources execute fails and keep producing
                     LOG.warn(e);
                 }
             }
@@ -218,7 +219,7 @@ public class ExecuteProduceConsume implements ExecutionStrategy, Runnable
                 }
                 catch(RejectedExecutionException e)
                 {
-                    // If we cannot execute, the close or discard the task and keep producing
+                    // If we cannot execute, then discard/reject the task and keep producing
                     LOG.debug(e);
                     LOG.warn("RejectedExecution {}",task);
                     try

jetty-util/src/main/java/org/eclipse/jetty/util/thread/strategy/ProduceExecuteConsume.java

@@ -62,7 +62,7 @@ public class ProduceExecuteConsume implements ExecutionStrategy
             }
             catch(RejectedExecutionException e)
             {
-                // Close or discard tasks that cannot be executed
+                //  Discard/reject tasks that cannot be executed
                 if (task instanceof Rejectable)
                 {
                     try