Comment fixes

helix-core/src/main/java/org/apache/helix/task/TaskUtil.java

@@ -1040,8 +1040,6 @@ public static void purgeExpiredJobs(String workflow, WorkflowConfig workflowConf
   /**
    * The function that loops through the all existing workflow contexts and removes IdealState and
    * workflow context of the workflow whose workflow config does not exist.
-   * Try-catch has been used to avoid concurrent modification exception while doing deep copy. Since
-   * Map.keySet() can produce concurrent modification exception.
    * @param dataProvider
    * @param manager
    */
@@ -1050,11 +1048,17 @@ public static void workflowGarbageCollection(final WorkflowControllerDataProvide
     // Garbage collections for conditions where workflow context exists but config is missing.
 
     Set<String> existingWorkflowContexts;
+    /*
+     * Here try-catch is used to avoid concurrent modification exception while doing deep copy.
+     * Map.keySet() can produce concurrent modification exception.
+     * Reason: If the map is modified while an iteration over the set is in progress, concurrent
+     * modification exception will be thrown.
+     */
     try {
       existingWorkflowContexts = new HashSet<>(dataProvider.getContexts().keySet());
     } catch (Exception e) {
       LOG.warn(
-          "Exception occurred while creating a list of all existing contexts with missing config!",
+          "Exception occurred while creating a list of all workflow context names!",
           e);
       return;
     }