From f91869d89d0e65911b700d75299f74f90dbd1355 Mon Sep 17 00:00:00 2001
From: Istvan Fajth <fapifta@gmail.com>
Date: Thu, 29 Aug 2024 23:33:15 +0200
Subject: [PATCH] HDDS-11392. ChecksumByteBufferImpl's static initializer fails
 with java 17+

---
 .../java/org/apache/hadoop/hdds/JavaUtils.java     | 14 +++++++++++++-
 .../ozone/common/ChecksumByteBufferImpl.java       | 14 ++++++++------
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/JavaUtils.java b/hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/JavaUtils.java
index 63c29ba7c912..804e6552488c 100644
--- a/hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/JavaUtils.java
+++ b/hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/JavaUtils.java
@@ -30,12 +30,24 @@ public final class JavaUtils {
    * is equal or greater than the parameter.
    *
    * @param version 8, 9, 10 etc.
-   * @return comparison with system property, always true for 8
+   * @return comparison with system property, always true for any int up to 8
    */
   public static boolean isJavaVersionAtLeast(int version) {
     return JAVA_SPEC_VER >= version;
   }
 
+  /**
+   * Query to see if major version of Java specification of the system
+   * is equal or less than the parameter.
+   *
+   * @param version 8, 9, 10 etc.
+   * @return comparison with system property
+   */
+  public static boolean isJavaVersionAtMost(int version) {
+    return JAVA_SPEC_VER <= version;
+  }
+
+
   /**
    * Private constructor.
    */
diff --git a/hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/common/ChecksumByteBufferImpl.java b/hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/common/ChecksumByteBufferImpl.java
index 1d596bf70077..a52359783270 100644
--- a/hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/common/ChecksumByteBufferImpl.java
+++ b/hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/common/ChecksumByteBufferImpl.java
@@ -44,12 +44,14 @@ public class ChecksumByteBufferImpl implements ChecksumByteBuffer {
 
   static {
     Field f = null;
-    try {
-      f = ByteBuffer.class
-          .getDeclaredField("isReadOnly");
-      f.setAccessible(true);
-    } catch (NoSuchFieldException e) {
-      LOG.error("No isReadOnly field in ByteBuffer", e);
+    if (JavaUtils.isJavaVersionAtMost(8)) {
+      try {
+        f = ByteBuffer.class
+            .getDeclaredField("isReadOnly");
+        f.setAccessible(true);
+      } catch (NoSuchFieldException e) {
+        LOG.error("No isReadOnly field in ByteBuffer", e);
+      }
     }
     IS_READY_ONLY_FIELD = f;