Comment on VarHandle

DaveCTurner · DaveCTurner · commit dbc155796530 · 2025-02-25T10:57:09.000Z
diff --git a/x-pack/plugin/write-load-forecaster/src/main/java/org/elasticsearch/xpack/writeloadforecaster/LicensedWriteLoadForecaster.java b/x-pack/plugin/write-load-forecaster/src/main/java/org/elasticsearch/xpack/writeloadforecaster/LicensedWriteLoadForecaster.java
@@ -166,6 +166,10 @@ public OptionalDouble getForecastedWriteLoad(IndexMetadata indexMetadata) {
         return indexMetadata.getForecastedWriteLoad();
     }
 
+    /**
+     * Used to atomically {@code getAndSet()} the {@link #hasValidLicence} field. This is better than an
+     * {@link java.util.concurrent.atomic.AtomicBoolean} because it takes one less pointer dereference on each read.
+     */
     private static final VarHandle VH_HAS_VALID_LICENCE_FIELD;
 
     static {

Original file line number	Diff line number	Diff line change
`@@ -166,6 +166,10 @@ public OptionalDouble getForecastedWriteLoad(IndexMetadata indexMetadata) {`
`166`	`166`	`return indexMetadata.getForecastedWriteLoad();`
`167`	`167`	`}`
`168`	`168`
	`169`	`+ /**`
	`170`	`+ * Used to atomically {@code getAndSet()} the {@link #hasValidLicence} field. This is better than an`
	`171`	`+ * {@link java.util.concurrent.atomic.AtomicBoolean} because it takes one less pointer dereference on each read.`
	`172`	`+ */`
`169`	`173`	`private static final VarHandle VH_HAS_VALID_LICENCE_FIELD;`
`170`	`174`
`171`	`175`	`static {`