From ad636a8035cc19f5a412b6b97b3f95ba37d0fe9a Mon Sep 17 00:00:00 2001
From: Matthew Swift <matthew.swift@forgerock.com>
Date: Fri, 30 Aug 2013 14:25:48 +0000
Subject: [PATCH] Back-port fix for OPENDJ-1112: LoadBalancing connection factories need better diagnostic messages
---
opendj-ldap-sdk/src/main/java/org/forgerock/opendj/ldap/AbstractLoadBalancingAlgorithm.java | 89 +++++++++++++++++++++++++++++++++++---------
1 files changed, 71 insertions(+), 18 deletions(-)
diff --git a/opendj-ldap-sdk/src/main/java/org/forgerock/opendj/ldap/AbstractLoadBalancingAlgorithm.java b/opendj-ldap-sdk/src/main/java/org/forgerock/opendj/ldap/AbstractLoadBalancingAlgorithm.java
index a868df4..cd99442 100644
--- a/opendj-ldap-sdk/src/main/java/org/forgerock/opendj/ldap/AbstractLoadBalancingAlgorithm.java
+++ b/opendj-ldap-sdk/src/main/java/org/forgerock/opendj/ldap/AbstractLoadBalancingAlgorithm.java
@@ -162,12 +162,17 @@
}
private void notifyOffline(final ErrorResultException error) {
+ // Save the error in case the load-balancer is exhausted.
+ lastFailure = error;
+
if (isOperational.getAndSet(false)) {
// Transition from online to offline.
- if (DEBUG_LOG.isLoggable(Level.WARNING)) {
- DEBUG_LOG.warning(String.format(
- "Connection factory '%s' is no longer operational: %s", factory, error
- .getMessage()));
+ synchronized (listenerLock) {
+ try {
+ listener.handleConnectionFactoryOffline(factory, error);
+ } catch (RuntimeException e) {
+ handleListenerException(e);
+ }
}
synchronized (stateLock) {
@@ -189,9 +194,12 @@
private void notifyOnline() {
if (!isOperational.getAndSet(true)) {
// Transition from offline to online.
- if (DEBUG_LOG.isLoggable(Level.INFO)) {
- DEBUG_LOG.info(String.format("Connection factory'%s' is now operational",
- factory));
+ synchronized (listenerLock) {
+ try {
+ listener.handleConnectionFactoryOnline(factory);
+ } catch (RuntimeException e) {
+ handleListenerException(e);
+ }
}
synchronized (stateLock) {
@@ -207,6 +215,13 @@
}
}
}
+
+ private void handleListenerException(RuntimeException e) {
+ if (DEBUG_LOG.isLoggable(Level.SEVERE)) {
+ DEBUG_LOG.log(Level.SEVERE,
+ "A run-time error occurred while processing a load-balancer event", e);
+ }
+ }
}
private final class MonitorRunnable implements Runnable {
@@ -222,9 +237,54 @@
}
}
+ /**
+ * A default event listener which just logs the event.
+ */
+ private static final LoadBalancerEventListener DEFAULT_LISTENER =
+ new LoadBalancerEventListener() {
+
+ @Override
+ public void handleConnectionFactoryOnline(ConnectionFactory factory) {
+ // Transition from offline to online.
+ if (DEBUG_LOG.isLoggable(Level.INFO)) {
+ DEBUG_LOG.info(String.format("Connection factory'%s' is now operational",
+ factory));
+ }
+ }
+
+ @Override
+ public void handleConnectionFactoryOffline(ConnectionFactory factory,
+ ErrorResultException error) {
+ if (DEBUG_LOG.isLoggable(Level.WARNING)) {
+ DEBUG_LOG.warning(String.format(
+ "Connection factory '%s' is no longer operational: %s", factory,
+ error.getMessage()));
+ }
+ }
+ };
+
private final List<MonitoredConnectionFactory> monitoredFactories;
private final ReferenceCountedObject<ScheduledExecutorService>.Reference scheduler;
private final Object stateLock = new Object();
+
+ /**
+ * The last connection failure which caused a connection factory to be
+ * marked offline. This is used in order to help diagnose problems when the
+ * load-balancer has exhausted all of its factories.
+ */
+ private volatile ErrorResultException lastFailure = null;
+
+ /**
+ * The event listener which should be notified when connection factories go
+ * on or off-line.
+ */
+ private final LoadBalancerEventListener listener;
+
+ /**
+ * Ensures that events are notified one at a time.
+ */
+ private final Object listenerLock = new Object();
+
/**
* Guarded by stateLock.
*/
@@ -237,17 +297,9 @@
private ScheduledFuture<?> monitoringFuture;
private AtomicBoolean isClosed = new AtomicBoolean();
- AbstractLoadBalancingAlgorithm(final Collection<ConnectionFactory> factories) {
- this(factories, 1, TimeUnit.SECONDS, null);
- }
-
AbstractLoadBalancingAlgorithm(final Collection<ConnectionFactory> factories,
- final long interval, final TimeUnit unit) {
- this(factories, interval, unit, null);
- }
-
- AbstractLoadBalancingAlgorithm(final Collection<ConnectionFactory> factories,
- final long interval, final TimeUnit unit, final ScheduledExecutorService scheduler) {
+ final LoadBalancerEventListener listener, final long interval, final TimeUnit unit,
+ final ScheduledExecutorService scheduler) {
Validator.ensureNotNull(factories, unit);
this.monitoredFactories = new ArrayList<MonitoredConnectionFactory>(factories.size());
@@ -258,6 +310,7 @@
this.scheduler = DEFAULT_SCHEDULER.acquireIfNull(scheduler);
this.monitoringInterval = interval;
this.monitoringIntervalTimeUnit = unit;
+ this.listener = listener != null ? listener : DEFAULT_LISTENER;
}
@Override
@@ -335,6 +388,6 @@
* timeout period.
*/
throw newErrorResult(ResultCode.CLIENT_SIDE_CONNECT_ERROR,
- "No operational connection factories available");
+ "No operational connection factories available", lastFailure);
}
}
--
Gitblit v1.10.0