FastThreadLocal#set remove duplicate isIndexedVariableSet call

Scottmitch · Scottmitch · commit f8a0eea7657c · 2017-12-22T09:42:12.000-08:00
Motivation:
FastThreadLocal#set calls isIndexedVariableSet to determine if we need to register with the cleaner, but the set(InternalThreadLocalMap, V) method will also internally do this check so we can share code and only do the check a single time.

Modifications:
- extract code from set(InternalThreadLocalMap, V) so it can be called externally to determine if a new item was created

Result:
Less code duplication in FastThreadLocal#set.
diff --git a/common/src/main/java/io/netty/util/concurrent/FastThreadLocal.java b/common/src/main/java/io/netty/util/concurrent/FastThreadLocal.java
@@ -16,8 +16,8 @@
 package io.netty.util.concurrent;
 
 import io.netty.util.internal.InternalThreadLocalMap;
-import io.netty.util.internal.PlatformDependent;
 import io.netty.util.internal.ObjectCleaner;
+import io.netty.util.internal.PlatformDependent;
 
 import java.util.Collections;
 import java.util.IdentityHashMap;
@@ -195,10 +195,7 @@ private V initialize(InternalThreadLocalMap threadLocalMap) {
     public final void set(V value) {
         if (value != InternalThreadLocalMap.UNSET) {
             InternalThreadLocalMap threadLocalMap = InternalThreadLocalMap.get();
-            boolean alreadySet = threadLocalMap.isIndexedVariableSet(index);
-            set(threadLocalMap, value);
-
-            if (!alreadySet) {
+            if (setKnownNotUnset(threadLocalMap, value)) {
                 registerCleaner(threadLocalMap);
             }
         } else {
@@ -211,14 +208,23 @@ public final void set(V value) {
      */
     public final void set(InternalThreadLocalMap threadLocalMap, V value) {
         if (value != InternalThreadLocalMap.UNSET) {
-            if (threadLocalMap.setIndexedVariable(index, value)) {
-                addToVariablesToRemove(threadLocalMap, this);
-            }
+            setKnownNotUnset(threadLocalMap, value);
         } else {
             remove(threadLocalMap);
         }
     }
 
+    /**
+     * @return see {@link InternalThreadLocalMap#setIndexedVariable(int, Object)}.
+     */
+    private boolean setKnownNotUnset(InternalThreadLocalMap threadLocalMap, V value) {
+        if (threadLocalMap.setIndexedVariable(index, value)) {
+            addToVariablesToRemove(threadLocalMap, this);
+            return true;
+        }
+        return false;
+    }
+
     /**
      * Returns {@code true} if and only if this thread-local variable is set.
      */
