Avoid leaking thread-locals in HikariBlockedTracker

mcculls · mcculls · commit 41f787cb77e5 · 2025-10-02T17:08:59.000+01:00
diff --git a/dd-java-agent/instrumentation/jdbc/src/main/java/datadog/trace/instrumentation/jdbc/HikariBlockedTracker.java b/dd-java-agent/instrumentation/jdbc/src/main/java/datadog/trace/instrumentation/jdbc/HikariBlockedTracker.java
@@ -1,18 +1,20 @@
 package datadog.trace.instrumentation.jdbc;
 
+import static java.lang.Boolean.TRUE;
+
 /** Shared blocked getConnection() tracking {@link ThreadLocal} for Hikari. */
 public class HikariBlockedTracker {
-  private static final ThreadLocal<Boolean> tracker = ThreadLocal.withInitial(() -> false);
+  private static final ThreadLocal<Boolean> tracker = new ThreadLocal<>();
 
   public static void clearBlocked() {
-    tracker.set(false);
+    tracker.remove();
   }
 
   public static void setBlocked() {
-    tracker.set(true);
+    tracker.set(TRUE);
   }
 
   public static boolean wasBlocked() {
-    return tracker.get();
+    return TRUE == tracker.get();
   }
 }
diff --git a/dd-java-agent/instrumentation/jdbc/src/main/java/datadog/trace/instrumentation/jdbc/HikariConcurrentBagInstrumentation.java b/dd-java-agent/instrumentation/jdbc/src/main/java/datadog/trace/instrumentation/jdbc/HikariConcurrentBagInstrumentation.java
@@ -99,8 +99,9 @@ public static void stopSpan(
         }
 
         span.finish();
+
+        HikariBlockedTracker.clearBlocked();
       }
-      HikariBlockedTracker.clearBlocked();
     }
   }
 }

Original file line number	Diff line number	Diff line change
`@@ -1,18 +1,20 @@`
`1`	`1`	`package datadog.trace.instrumentation.jdbc;`
`2`	`2`
	`3`	`+import static java.lang.Boolean.TRUE;`
	`4`	`+`
`3`	`5`	`/** Shared blocked getConnection() tracking {@link ThreadLocal} for Hikari. */`
`4`	`6`	`public class HikariBlockedTracker {`
`5`		`- private static final ThreadLocal<Boolean> tracker = ThreadLocal.withInitial(() -> false);`
	`7`	`+ private static final ThreadLocal<Boolean> tracker = new ThreadLocal<>();`
`6`	`8`
`7`	`9`	`public static void clearBlocked() {`
`8`		`- tracker.set(false);`
	`10`	`+ tracker.remove();`
`9`	`11`	`}`
`10`	`12`
`11`	`13`	`public static void setBlocked() {`
`12`		`- tracker.set(true);`
	`14`	`+ tracker.set(TRUE);`
`13`	`15`	`}`
`14`	`16`
`15`	`17`	`public static boolean wasBlocked() {`
`16`		`- return tracker.get();`
	`18`	`+ return TRUE == tracker.get();`
`17`	`19`	`}`
`18`	`20`	`}`
Original file line number	Diff line number	Diff line change
`@@ -99,8 +99,9 @@ public static void stopSpan(`
`99`	`99`	`}`
`100`	`100`
`101`	`101`	`span.finish();`
	`102`	`+`
	`103`	`+ HikariBlockedTracker.clearBlocked();`
`102`	`104`	`}`
`103`		`- HikariBlockedTracker.clearBlocked();`
`104`	`105`	`}`
`105`	`106`	`}`
`106`	`107`	`}`