diff --git a/ebean-api/src/main/java/io/ebean/bean/MutableHash.java b/ebean-api/src/main/java/io/ebean/bean/MutableHash.java
index aa5ea29df..d59421980 100644
--- a/ebean-api/src/main/java/io/ebean/bean/MutableHash.java
+++ b/ebean-api/src/main/java/io/ebean/bean/MutableHash.java
@@ -4,25 +4,26 @@ package io.ebean.bean;
  * Interface to for mutable information in EntityBeanIntercept.
  */
 public interface MutableHash {
-  
+
   /**
-   * Compares the given json to an internal value. Can be a MD5 hash or a plain JSON string. 
+   * Compares the given json to an internal value. Can be a MD5 hash or a plain JSON string.
+   *
    * @return true if the value matches the hash.
    */
   boolean isEqualToJson(String json);
 
   /**
-   * Compares the given object to an internal value. This is an optional method, but required for proper changelog/beanState support.
+   * Compares the given object to an internal value. Required for proper changelog/beanState support.
    * The implementation can serialize the object and compare it against the original json.
    */
-  default boolean isEqualToObject(Object obj) {
-    return true;
-  }
+  boolean isEqualToObject(Object obj);
+
   /**
-   * Creates a new instance from the internal json string. This is an optional method.
+   * Creates a new instance from the internal json string.
+   * <p>
+   * This is used to provide an original/old value for change logging / persist listeners.
    */
   default Object get() {
     return null;
   }
 }
- 
\ No newline at end of file
diff --git a/ebean-core/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyJsonMapper.java b/ebean-core/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyJsonMapper.java
index 747df5130..b1838ff18 100644
--- a/ebean-core/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyJsonMapper.java
+++ b/ebean-core/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyJsonMapper.java
@@ -96,11 +96,11 @@ public class BeanPropertyJsonMapper extends BeanProperty {
   private static class JsonMutableHash implements MutableHash {
 
     private final String originalJson;
-    private ScalarType<?> parent;
+    private final ScalarType<?> parent;
 
     JsonMutableHash(ScalarType<?> parent, String json) {
       this.parent = parent;
-      originalJson = json;
+      this.originalJson = json;
     }
 
     @Override