SLING-3059 - Log stack trace when ClassLoaderFacade detects inactive manager
git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1522872 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/main/java/org/apache/sling/commons/classloader/impl/ClassLoaderFacade.java b/src/main/java/org/apache/sling/commons/classloader/impl/ClassLoaderFacade.java
index b3c2d20..84f54bd 100644
--- a/src/main/java/org/apache/sling/commons/classloader/impl/ClassLoaderFacade.java
+++ b/src/main/java/org/apache/sling/commons/classloader/impl/ClassLoaderFacade.java
@@ -43,6 +43,14 @@
/** Dynamic class loader manager which manages the dynamic class loader providers for this facade. */
private final DynamicClassLoaderManagerImpl manager;
+
+ /** Used to log stack traces in slf4j for non-critical errors */
+ @SuppressWarnings("serial")
+ static class StackTraceProbe extends Exception {
+ StackTraceProbe(String reason) {
+ super(reason);
+ }
+ }
/**
* Constructor
@@ -51,12 +59,24 @@
this.manager = manager;
}
+ /** Return false if our manager is not active, and log the stack trace
+ * when that happens, to ease troubleshooting.
+ */
+ private boolean checkManagerActive() {
+ if(!this.manager.isActive()) {
+ final String msg = "Dynamic class loader has already been deactivated.";
+ final StackTraceProbe p = new StackTraceProbe(msg);
+ logger.error(msg, p);
+ return false;
+ }
+ return true;
+ }
+
/**
* @see java.lang.ClassLoader#getResource(java.lang.String)
*/
public URL getResource(String name) {
- if ( !this.manager.isActive() ) {
- logger.error("Dynamic class loader has already been deactivated.");
+ if (!checkManagerActive()) {
return null;
}
final ClassLoader[] loaders = manager.getDynamicClassLoaders();
@@ -81,8 +101,7 @@
* @see java.lang.ClassLoader#getResources(java.lang.String)
*/
public Enumeration<URL> getResources(String name) throws IOException {
- if ( !this.manager.isActive() ) {
- logger.error("Dynamic class loader has already been deactivated.");
+ if(!checkManagerActive()) {
return Collections.enumeration(EMPTY_LIST);
}
final ClassLoader[] loaders = manager.getDynamicClassLoaders();
@@ -107,8 +126,7 @@
*/
protected synchronized Class<?> loadClass(String name, boolean resolve)
throws ClassNotFoundException {
- if ( !this.manager.isActive() ) {
- logger.error("Dynamic class loader has already been deactivated.");
+ if(!checkManagerActive()) {
throw new ClassNotFoundException(name);
}
final ClassLoader[] loaders = manager.getDynamicClassLoaders();
