From 1f35e7c99b66b8d46c4ad96558e694a10aa38062 Mon Sep 17 00:00:00 2001
From: Matthew Jason Benson <mbenson@apache.org>
Date: Sun, 7 Feb 2010 03:14:09 +0000
Subject: [PATCH] [LANG-586] Clear ThreadLocal for HashCodeBuilder as well

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@907373 13f79535-47bb-0310-9956-ffa450edef68
---
 .../lang3/builder/HashCodeBuilder.java        | 29 ++++++++++++-------
 .../lang3/builder/HashCodeBuilderTest.java    |  2 ++
 2 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/src/main/java/org/apache/commons/lang3/builder/HashCodeBuilder.java b/src/main/java/org/apache/commons/lang3/builder/HashCodeBuilder.java
index 547676ccb..9f7e8903b 100644
--- a/src/main/java/org/apache/commons/lang3/builder/HashCodeBuilder.java
+++ b/src/main/java/org/apache/commons/lang3/builder/HashCodeBuilder.java
@@ -101,14 +101,7 @@ public class HashCodeBuilder {
      * 
      * @since 2.3
      */
-    private static final ThreadLocal<Set<IDKey>> registry = new ThreadLocal<Set<IDKey>>() {
-        @Override
-        protected Set<IDKey> initialValue() {
-            // The HashSet implementation is not synchronized,
-            // which is just what we need here.
-            return new HashSet<IDKey>();
-        }
-    };
+    private static final ThreadLocal<Set<IDKey>> REGISTRY = new ThreadLocal<Set<IDKey>>();
 
     /*
      * N.B. we cannot store the actual objects in a HashSet, as that would use the very hashCode()
@@ -136,7 +129,7 @@ public class HashCodeBuilder {
      * @since 2.3
      */
     static Set<IDKey> getRegistry() {
-        return registry.get();
+        return REGISTRY.get();
     }
 
     /**
@@ -151,7 +144,8 @@ public class HashCodeBuilder {
      * @since 2.3
      */
     static boolean isRegistered(Object value) {
-        return getRegistry().contains(new IDKey(value));
+        Set<IDKey> registry = getRegistry();
+        return registry != null && registry.contains(new IDKey(value));
     }
 
     /**
@@ -521,6 +515,11 @@ public class HashCodeBuilder {
      *            The object to register.
      */
     static void register(Object value) {
+        synchronized (HashCodeBuilder.class) {
+            if (getRegistry() == null) {
+                REGISTRY.set(new HashSet<IDKey>());
+            }
+        }
         getRegistry().add(new IDKey(value));
     }
 
@@ -537,7 +536,15 @@ public class HashCodeBuilder {
      * @since 2.3
      */
     static void unregister(Object value) {
-        getRegistry().remove(new IDKey(value));
+        Set<IDKey> s = getRegistry();
+        if (s != null) {
+            s.remove(new IDKey(value));
+            synchronized (HashCodeBuilder.class) {
+                if (s.isEmpty()) {
+                    REGISTRY.remove();
+                }
+            }
+        }
     }
 
     /**
diff --git a/src/test/java/org/apache/commons/lang3/builder/HashCodeBuilderTest.java b/src/test/java/org/apache/commons/lang3/builder/HashCodeBuilderTest.java
index f6af5f035..64b34f907 100644
--- a/src/test/java/org/apache/commons/lang3/builder/HashCodeBuilderTest.java
+++ b/src/test/java/org/apache/commons/lang3/builder/HashCodeBuilderTest.java
@@ -521,7 +521,9 @@ public class HashCodeBuilderTest extends TestCase {
         // at org.apache.commons.lang.builder.HashCodeBuilder.append(HashCodeBuilder.java:422)
 
         a.hashCode();
+        assertNull(HashCodeBuilder.getRegistry());
         b.hashCode();
+        assertNull(HashCodeBuilder.getRegistry());
     }
 
     /**