diff a/src/java.xml.crypto/share/classes/javax/xml/crypto/URIReferenceException.java b/src/java.xml.crypto/share/classes/javax/xml/crypto/URIReferenceException.java
--- a/src/java.xml.crypto/share/classes/javax/xml/crypto/URIReferenceException.java
+++ b/src/java.xml.crypto/share/classes/javax/xml/crypto/URIReferenceException.java
@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
@@ -55,10 +55,14 @@
      *
      * @serial
      */
     private Throwable cause;
 
+    /**
+     * The {@code URIReference} that was being dereferenced
+     * when the exception was thrown, or {@code null} if not specified.
+     */
     private URIReference uriReference;
 
     /**
      * Constructs a new {@code URIReferenceException} with
      * {@code null} as its detail message.
