8304557: java/util/concurrent/CompletableFuture/CompletableFutureOrTimeoutExceptionallyTest.java times out

Reviewed-by: jpai

Author: viktorklang-ora

test/jdk/java/util/concurrent/CompletableFuture/CompletableFutureOrTimeoutExceptionallyTest.java

@@ -25,39 +25,59 @@
  * @test
  * @bug 8303742
  * @summary CompletableFuture.orTimeout can leak memory if completed exceptionally
+ * @modules java.base/java.util.concurrent:open
  * @run junit/othervm -Xmx128m CompletableFutureOrTimeoutExceptionallyTest
  */
 
 import java.time.Duration;
+import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
 import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 class CompletableFutureOrTimeoutExceptionallyTest {
+    static final BlockingQueue<Runnable> delayerQueue;
+    static {
+        try {
+            var delayerClass = Class.forName("java.util.concurrent.CompletableFuture$Delayer",
+                                             true,
+                                             CompletableFuture.class.getClassLoader());
+            var delayerField = delayerClass.getDeclaredField("delayer");
+            delayerField.setAccessible(true);
+            delayerQueue = ((ScheduledThreadPoolExecutor)delayerField.get(null)).getQueue();
+        } catch (Throwable t) {
+            throw new ExceptionInInitializerError(t);
+        }
+    }
+
     /**
      * Test that orTimeout task is cancelled if the CompletableFuture is completed Exceptionally
      */
     @Test
-    void testOrTimeoutWithCompleteExceptionallyDoesNotLeak() {
-        var count = 0L;
-        while (count++ < 2_000_000) {
-            new CompletableFuture<>()
-            .orTimeout(12, TimeUnit.HOURS)
-            .completeExceptionally(new RuntimeException("This is fine"));
-        }
+    void testOrTimeoutWithCompleteExceptionallyDoesNotLeak() throws InterruptedException {
+        assertTrue(delayerQueue.peek() == null);
+        var future = new CompletableFuture<>().orTimeout(12, TimeUnit.HOURS);
+        assertTrue(delayerQueue.peek() != null);
+        future.completeExceptionally(new RuntimeException("This is fine"));
+        while (delayerQueue.peek() != null) {
+            Thread.sleep(100);
+        };
     }
 
     /**
      * Test that the completeOnTimeout task is cancelled if the CompletableFuture is completed Exceptionally
      */
     @Test
-    void testCompleteOnTimeoutWithCompleteExceptionallyDoesNotLeak() {
-        var count = 0L;
-        while (count++ < 2_000_000) {
-            new CompletableFuture<>()
-            .completeOnTimeout(null, 12, TimeUnit.HOURS)
-            .completeExceptionally(new RuntimeException("This is fine"));
-        }
+    void testCompleteOnTimeoutWithCompleteExceptionallyDoesNotLeak() throws InterruptedException {
+        assertTrue(delayerQueue.peek() == null);
+        var future = new CompletableFuture<>().completeOnTimeout(null, 12, TimeUnit.HOURS);
+        assertTrue(delayerQueue.peek() != null);
+        future.completeExceptionally(new RuntimeException("This is fine"));
+        while (delayerQueue.peek() != null) {
+            Thread.sleep(100);
+        };
     }
 }