From 3d1ce65a6e0c466bfd0c2c8dd4978a730ec4cf1a Mon Sep 17 00:00:00 2001
From: Ryan McKinley <ryan@apache.org>
Date: Mon, 7 Jul 2008 20:19:37 +0000
Subject: [PATCH] SOLR-605 -- adding thread safety comment

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/trunk@674619 13f79535-47bb-0310-9956-ffa450edef68
---
 src/java/org/apache/solr/core/SolrCore.java   | 22 +++++++++++++++++++
 .../org/apache/solr/update/UpdateHandler.java | 14 ++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/src/java/org/apache/solr/core/SolrCore.java b/src/java/org/apache/solr/core/SolrCore.java
index 903366ecb1d..0f3eadb9da4 100644
--- a/src/java/org/apache/solr/core/SolrCore.java
+++ b/src/java/org/apache/solr/core/SolrCore.java
@@ -44,6 +44,7 @@ import org.apache.solr.update.processor.UpdateRequestProcessorFactory;
 import org.apache.solr.util.RefCounted;
 import org.apache.solr.util.plugin.AbstractPluginLoader;
 import org.apache.solr.util.plugin.NamedListPluginLoader;
+import org.apache.solr.util.plugin.SolrCoreAware;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 import org.xml.sax.SAXException;
@@ -207,16 +208,37 @@ public final class SolrCore {
     newSearcherListeners = parseListener("//listener[@event=\"newSearcher\"]");
   }
   
+  /**
+   * NOTE: this function is not thread safe.  However, it is safe to call within the
+   * <code>inform( SolrCore core )</code> function for <code>SolrCoreAware</code> classes.
+   * Outside <code>inform</code>, this could potentially throw a ConcurrentModificationException
+   * 
+   * @see SolrCoreAware
+   */
   public void registerFirstSearcherListener( SolrEventListener listener )
   {
     firstSearcherListeners.add( listener );
   }
 
+  /**
+   * NOTE: this function is not thread safe.  However, it is safe to call within the
+   * <code>inform( SolrCore core )</code> function for <code>SolrCoreAware</code> classes.
+   * Outside <code>inform</code>, this could potentially throw a ConcurrentModificationException
+   * 
+   * @see SolrCoreAware
+   */
   public void registerNewSearcherListener( SolrEventListener listener )
   {
     newSearcherListeners.add( listener );
   }
 
+  /**
+   * NOTE: this function is not thread safe.  However, it is safe to call within the
+   * <code>inform( SolrCore core )</code> function for <code>SolrCoreAware</code> classes.
+   * Outside <code>inform</code>, this could potentially throw a ConcurrentModificationException
+   * 
+   * @see SolrCoreAware
+   */
   public void registerResponseWriter( String name, QueryResponseWriter responseWriter ){
     responseWriters.put(name, responseWriter);
   }
diff --git a/src/java/org/apache/solr/update/UpdateHandler.java b/src/java/org/apache/solr/update/UpdateHandler.java
index e84daf14924..9b4f8acd42d 100644
--- a/src/java/org/apache/solr/update/UpdateHandler.java
+++ b/src/java/org/apache/solr/update/UpdateHandler.java
@@ -179,11 +179,25 @@ public abstract class UpdateHandler implements SolrInfoMBean {
   }
 
 
+  /**
+   * NOTE: this function is not thread safe.  However, it is safe to call within the
+   * <code>inform( SolrCore core )</code> function for <code>SolrCoreAware</code> classes.
+   * Outside <code>inform</code>, this could potentially throw a ConcurrentModificationException
+   * 
+   * @see SolrCoreAware
+   */
   public void registerCommitCallback( SolrEventListener listener )
   {
     commitCallbacks.add( listener );
   }
 
+  /**
+   * NOTE: this function is not thread safe.  However, it is safe to call within the
+   * <code>inform( SolrCore core )</code> function for <code>SolrCoreAware</code> classes.
+   * Outside <code>inform</code>, this could potentially throw a ConcurrentModificationException
+   * 
+   * @see SolrCoreAware
+   */
   public void registerOptimizeCallback( SolrEventListener listener )
   {
     optimizeCallbacks.add( listener );