[logback-dev] svn commit: r1602 - in logback/trunk/logback-core/src/main/java/ch/qos/logback/core: . util

[noreply.ceki at qos.ch]

Author: ceki
Date: Tue Nov 13 11:41:22 2007
New Revision: 1602

Modified:
   logback/trunk/logback-core/src/main/java/ch/qos/logback/core/BasicStatusManager.java
   logback/trunk/logback-core/src/main/java/ch/qos/logback/core/util/StatusPrinter.java

Log:
Synchronizing on ConcurrentModificationException in order to avoid ConcurrentModificationException
exceptions on the list maintained by ConcurrentModificationException, as shown below

java.util.ConcurrentModificationException
        at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:449)
        at java.util.AbstractList$Itr.next(AbstractList.java:420)
        at ch.qos.logback.core.util.StatusPrinter.print(StatusPrinter.java:47)
        at ch.qos.logback.core.util.StatusPrinter.print(StatusPrinter.java:38)
        at ch.qos.logback.audit.server.AuditServerTest.testUnreachable(AuditServerTest.java:137)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        
This can happen if multiple thread access BasicStatusManager simultaneously.

Modified: logback/trunk/logback-core/src/main/java/ch/qos/logback/core/BasicStatusManager.java
==============================================================================
--- logback/trunk/logback-core/src/main/java/ch/qos/logback/core/BasicStatusManager.java	(original)
+++ logback/trunk/logback-core/src/main/java/ch/qos/logback/core/BasicStatusManager.java	Tue Nov 13 11:41:22 2007
@@ -9,7 +9,6 @@
  */
 package ch.qos.logback.core;
 
-
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
@@ -20,19 +19,22 @@
 public class BasicStatusManager implements StatusManager {
 
   public static final int MAX_COUNT = 200;
-  
+
   int count = 0;
   List<Status> statusList = new ArrayList<Status>();
   int level = Status.INFO;
-  
-  public void add(Status newStatus) {
-    //System.out.println(newStatus);
-    if(count > MAX_COUNT) {
+
+  // This method is synchronized on the instance.
+  // Code iterating on this.iterator is expected to
+  // also synchronize on this (the BasicStatusManager instance)
+  public synchronized void add(Status newStatus) {
+    // System.out.println(newStatus);
+    if (count > MAX_COUNT) {
       return;
     }
     count++;
-    
-    if(newStatus.getLevel() > level) {
+
+    if (newStatus.getLevel() > level) {
       level = newStatus.getLevel();
     }
     statusList.add(newStatus);
@@ -47,8 +49,7 @@
   }
 
   public int getCount() {
-	return count;
+    return count;
   }
 
-  
 }

Modified: logback/trunk/logback-core/src/main/java/ch/qos/logback/core/util/StatusPrinter.java
==============================================================================
--- logback/trunk/logback-core/src/main/java/ch/qos/logback/core/util/StatusPrinter.java	(original)
+++ logback/trunk/logback-core/src/main/java/ch/qos/logback/core/util/StatusPrinter.java	Tue Nov 13 11:41:22 2007
@@ -41,12 +41,12 @@
   }
 
   public static void print(StatusManager sm) {
-
-    Iterator it = sm.iterator();
-    while (it.hasNext()) {
-      Status s = (Status) it.next();
-      print("", s);
-     
+    synchronized (sm) {
+      Iterator it = sm.iterator();
+      while (it.hasNext()) {
+        Status s = (Status) it.next();
+        print("", s);
+      }
     }
   }