This is an automated email from the ASF dual-hosted git repository.
dlmarion pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/accumulo-classloaders.git
The following commit(s) were added to refs/heads/main by this push:
new 0dadf6c Remove ContextDefinition on unhandled exception in Monitor
task (#50)
0dadf6c is described below
commit 0dadf6cc89809c0dd6035b3b3c07df0d7776a2d5
Author: Dave Marion <[email protected]>
AuthorDate: Tue Jan 20 16:59:26 2026 -0500
Remove ContextDefinition on unhandled exception in Monitor task (#50)
Closes #46
---
.../lcc/LocalCachingContextClassLoaderFactory.java | 42 ++++++++++++++++++----
1 file changed, 35 insertions(+), 7 deletions(-)
diff --git
a/modules/local-caching-classloader/src/main/java/org/apache/accumulo/classloader/lcc/LocalCachingContextClassLoaderFactory.java
b/modules/local-caching-classloader/src/main/java/org/apache/accumulo/classloader/lcc/LocalCachingContextClassLoaderFactory.java
index 94fed63..2c185a6 100644
---
a/modules/local-caching-classloader/src/main/java/org/apache/accumulo/classloader/lcc/LocalCachingContextClassLoaderFactory.java
+++
b/modules/local-caching-classloader/src/main/java/org/apache/accumulo/classloader/lcc/LocalCachingContextClassLoaderFactory.java
@@ -99,7 +99,7 @@ public class LocalCachingContextClassLoaderFactory implements
ContextClassLoader
private static final Logger LOG =
LoggerFactory.getLogger(LocalCachingContextClassLoaderFactory.class);
- private final ScheduledExecutorService EXECUTOR =
Executors.newScheduledThreadPool(0);
+ private final ScheduledExecutorService executor =
Executors.newScheduledThreadPool(0);
// stores the latest seen ContextDefinition for a remote URL location;
String types are used here
// for the key instead of URL because URL.hashCode could trigger network
activity for hostname
@@ -119,13 +119,24 @@ public class LocalCachingContextClassLoaderFactory
implements ContextClassLoader
/**
* Schedule a task to execute at {@code interval} seconds to update the
LocalCachingContext if the
* ContextDefinition has changed. The task schedules a follow-on task at the
update interval value
- * (if it changed).
+ * (if it changed) and the task is successful or throws a handled exception.
When an unhandled
+ * exception is thrown, then the corresponding entry in the contextDefs map
is cleared. The next
+ * call to {@code #getClassLoader(String)} will recreate the contextDefs map
entry and schedule
+ * the monitor task.
*/
private void monitorContext(final String contextLocation, long interval) {
LOG.trace("Monitoring context definition file {} for changes at {} second
intervals",
contextLocation, interval);
- EXECUTOR.schedule(() -> checkMonitoredLocation(contextLocation, interval),
interval,
- TimeUnit.SECONDS);
+ executor.schedule(() -> {
+ try {
+ checkMonitoredLocation(contextLocation, interval);
+ } catch (Throwable t) {
+ LOG.error("Unhandled exception occurred in context definition monitor
thread. Removing"
+ + " context definition {}.", contextLocation, t);
+ contextDefs.remove(contextLocation);
+ throw t;
+ }
+ }, interval, TimeUnit.SECONDS);
}
@Override
@@ -268,6 +279,15 @@ public class LocalCachingContextClassLoaderFactory
implements ContextClassLoader
} else {
LOG.trace("Context definition for {} has not changed",
contextLocation);
}
+ // reschedule this task to run if the context definition exists.
+ // Atomically lock on the context key and only reschedule if the context
is present.
+ final long finalMonitorInterval = nextInterval;
+ contextDefs.compute(contextLocation, (k, v) -> {
+ if (v != null) {
+ monitorContext(contextLocation, finalMonitorInterval);
+ }
+ return v;
+ });
} catch (IOException | RuntimeException e) {
LOG.error("Error parsing updated context definition at {}. Classloader
NOT updated!",
contextLocation, e);
@@ -294,10 +314,18 @@ public class LocalCachingContextClassLoaderFactory
implements ContextClassLoader
LOG.trace("Failing to update classloader for context {} within the
grace period",
contextLocation, e);
}
- } finally {
- monitorContext(contextLocation, nextInterval);
+ // reschedule this task to run if the context definition exists.
+ // Don't put this in finally block as we only want to reschedule
+ // on success or handled exception
+ // Atomically lock on the context key and only reschedule if the context
is present.
+ final long finalMonitorInterval = nextInterval;
+ contextDefs.compute(contextLocation, (k, v) -> {
+ if (v != null) {
+ monitorContext(contextLocation, finalMonitorInterval);
+ }
+ return v;
+ });
}
-
}
public static Map<String,List<String>> getReferencedFiles() {
