From bf52eb035865353fdf5c6c242f9676a51dcc9e22 Mon Sep 17 00:00:00 2001
From: Brent Christian <bchristi@openjdk.org>
Date: Tue, 29 Apr 2025 20:15:00 +0000
Subject: [PATCH] 8355632: WhiteBox.waitForReferenceProcessing() fails assert
 for return type

Reviewed-by: kbarrett
---
 .../jdk/test/whitebox/WaitForRefProcTest.java | 30 +++++++++++++++++++
 test/lib/jdk/test/whitebox/WhiteBox.java      |  2 +-
 2 files changed, 31 insertions(+), 1 deletion(-)
 create mode 100644 test/lib-test/jdk/test/whitebox/WaitForRefProcTest.java

diff --git a/test/lib-test/jdk/test/whitebox/WaitForRefProcTest.java b/test/lib-test/jdk/test/whitebox/WaitForRefProcTest.java
new file mode 100644
index 00000000000..1a254775f77
--- /dev/null
+++ b/test/lib-test/jdk/test/whitebox/WaitForRefProcTest.java
@@ -0,0 +1,30 @@
+/*
+ * @test
+ * @summary Test WhiteBox.waitForReferenceProcessing
+ * @bug 8305186 8355632
+ * @library /test/lib
+ * @build jdk.test.whitebox.WhiteBox
+ * @modules java.base/java.lang.ref:open
+ * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
+ * @run main/othervm -ea -esa
+ *      -Xbootclasspath/a:.
+ *      -XX:+UnlockDiagnosticVMOptions
+ *      -XX:+WhiteBoxAPI
+ *      WaitForRefProcTest
+ */
+
+import jdk.test.whitebox.WhiteBox;
+
+public class WaitForRefProcTest {
+
+    public static void main(String[] args) {
+        WhiteBox.getWhiteBox().fullGC();
+        try {
+            boolean ret = WhiteBox.getWhiteBox().waitForReferenceProcessing();
+            System.out.println("wFRP returned " + ret);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+            throw new RuntimeException("test caught InterruptedException");
+        }
+    }
+}
diff --git a/test/lib/jdk/test/whitebox/WhiteBox.java b/test/lib/jdk/test/whitebox/WhiteBox.java
index bd68cf72cc3..4747740274e 100644
--- a/test/lib/jdk/test/whitebox/WhiteBox.java
+++ b/test/lib/jdk/test/whitebox/WhiteBox.java
@@ -569,7 +569,7 @@ public class WhiteBox {
       try {
         wfrp = Reference.class.getDeclaredMethod("waitForReferenceProcessing");
         wfrp.setAccessible(true);
-        assert wfrp.getReturnType() == Boolean.class;
+        assert wfrp.getReturnType().equals(boolean.class);
         Class<?>[] ev = wfrp.getExceptionTypes();
         assert ev.length == 1;
         assert ev[0] == InterruptedException.class;