# HG changeset patch # User sjiang # Date 1410517167 -7200 # Node ID b561a19107c732d36f38ce6c58edb554922c2b86 # Parent 9d0e6639a4d71b63507dd94b1a028e963b27e798 8049303: Transient network problems cause JMX thread to fail silenty Reviewed-by: dfuchs, jbachorik diff -r 9d0e6639a4d7 -r b561a19107c7 jdk/src/java.management/share/classes/javax/management/remote/rmi/RMIConnector.java --- a/jdk/src/java.management/share/classes/javax/management/remote/rmi/RMIConnector.java Wed Jul 05 20:01:04 2017 +0200 +++ b/jdk/src/java.management/share/classes/javax/management/remote/rmi/RMIConnector.java Fri Sep 12 12:19:27 2014 +0200 @@ -1335,66 +1335,94 @@ int maxNotifications, long timeout) throws IOException, ClassNotFoundException { - IOException org; + boolean retried = false; while (true) { // used for a successful re-connection + // or a transient network problem try { return connection.fetchNotifications(clientSequenceNumber, maxNotifications, - timeout); + timeout); // return normally } catch (IOException ioe) { - org = ioe; + // Examine the chain of exceptions to determine whether this + // is a deserialization issue. If so - we propagate the + // appropriate exception to the caller, who will then + // proceed with fetching notifications one by one + rethrowDeserializationException(ioe); - // inform of IOException try { communicatorAdmin.gotIOException(ioe); - - // The connection should be re-established. - continue; + // reconnection OK, back to "while" to do again } catch (IOException ee) { - // No more fetch, the Exception will be re-thrown. - break; - } // never reached - } // never reached - } + boolean toClose = false; - // specially treating for an UnmarshalException - if (org instanceof UnmarshalException) { - UnmarshalException ume = (UnmarshalException)org; - - if (ume.detail instanceof ClassNotFoundException) - throw (ClassNotFoundException) ume.detail; + synchronized (this) { + if (terminated) { + // the connection is closed. + throw ioe; + } else if (retried) { + toClose = true; + } + } - /* In Sun's RMI implementation, if a method return - contains an unserializable object, then we get - UnmarshalException wrapping WriteAbortedException - wrapping NotSerializableException. In that case we - extract the NotSerializableException so that our - caller can realize it should try to skip past the - notification that presumably caused it. It's not - certain that every other RMI implementation will - generate this exact exception sequence. If not, we - will not detect that the problem is due to an - unserializable object, and we will stop trying to - receive notifications from the server. It's not - clear we can do much better. */ - if (ume.detail instanceof WriteAbortedException) { - WriteAbortedException wae = - (WriteAbortedException) ume.detail; - if (wae.detail instanceof IOException) - throw (IOException) wae.detail; + if (toClose) { + // JDK-8049303 + // We received an IOException - but the communicatorAdmin + // did not close the connection - possibly because + // the original exception was raised by a transient network + // problem? + // We already know that this exception is not due to a deserialization + // issue as we already took care of that before involving the + // communicatorAdmin. Moreover - we already made one retry attempt + // at fetching the same batch of notifications - and the + // problem persisted. + // Since trying again doesn't seem to solve the issue, we will now + // close the connection. Doing otherwise might cause the + // NotifFetcher thread to die silently. + final Notification failedNotif = + new JMXConnectionNotification( + JMXConnectionNotification.FAILED, + this, + connectionId, + clientNotifSeqNo++, + "Failed to communicate with the server: " + ioe.toString(), + ioe); + + sendNotification(failedNotif); + + try { + close(true); + } catch (Exception e) { + // OK. + // We are closing + } + throw ioe; // the connection is closed here. + } else { + // JDK-8049303 possible transient network problem, + // let's try one more time + retried = true; + } + } } - } else if (org instanceof MarshalException) { + } + } + + private void rethrowDeserializationException(IOException ioe) + throws ClassNotFoundException, IOException { + // specially treating for an UnmarshalException + if (ioe instanceof UnmarshalException) { + throw ioe; // the fix of 6937053 made ClientNotifForwarder.fetchNotifs + // fetch one by one with UnmarshalException + } else if (ioe instanceof MarshalException) { // IIOP will throw MarshalException wrapping a NotSerializableException // when a server fails to serialize a response. - MarshalException me = (MarshalException)org; + MarshalException me = (MarshalException)ioe; if (me.detail instanceof NotSerializableException) { throw (NotSerializableException)me.detail; } } - // Not serialization problem, simply re-throw the orginal exception - throw org; + // Not serialization problem, return. } protected Integer addListenerForMBeanRemovedNotif()