Consistent final declaration for static delegate classes

Issue: SPR-16968

spring-beans/src/main/java/org/springframework/beans/PropertyAccessorFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2008 the original author or authors.
+ * Copyright 2002-2018 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,7 +24,11 @@ package org.springframework.beans;
  * @author Juergen Hoeller
  * @since 2.5.2
  */
-public abstract class PropertyAccessorFactory {
+public final class PropertyAccessorFactory {
+
+	private PropertyAccessorFactory() {
+	}
+
 
 	/**
 	 * Obtain a BeanWrapper for the given target object,