Here's a change to make "lookup" fields be more memory-model-correct:

diff --git a/src/java.base/share/classes/java/util/ListResourceBundle.java b/src/java.base/share/classes/java/util/ListResourceBundle.java
--- a/src/java.base/share/classes/java/util/ListResourceBundle.java
+++ b/src/java.base/share/classes/java/util/ListResourceBundle.java
@@ -206,5 +206,5 @@
         lookup = temp;
     }
 
- private Map<String,Object> lookup = null;
+ private volatile Map<String,Object> lookup = null;
 }
diff --git a/src/java.base/share/classes/java/util/PropertyResourceBundle.java b/src/java.base/share/classes/java/util/PropertyResourceBundle.java
--- a/src/java.base/share/classes/java/util/PropertyResourceBundle.java
+++ b/src/java.base/share/classes/java/util/PropertyResourceBundle.java
@@ -236,5 +236,5 @@
 
     // ==================privates====================
 
- private Map<String,Object> lookup;
+ private final Map<String,Object> lookup;
 }