DATACMNS-909 - Mask getDecoratedClass() of Spring 4.3's DecoratingProxy.

The proxies created for projections now defensively mask getDecoratedClass(), a method declared on DecoratingProxy, an interface that JDK proxies on Spring 4.3 will implement.

src/main/java/org/springframework/data/projection/TargetAware.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2016 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.
@@ -16,6 +16,7 @@
 package org.springframework.data.projection;
 
 import org.springframework.aop.RawTargetAccess;
+import org.springframework.core.DecoratingProxy;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 
@@ -41,4 +42,13 @@ public interface TargetAware extends org.springframework.aop.TargetClassAware, R
 	 */
 	@JsonIgnore
 	Object getTarget();
+
+	/**
+	 * Re-declaration of Spring Framework 4.3's {@link DecoratingProxy#getDecoratedClass()} so that we can exclude it from
+	 * Jackson serialization.
+	 * 
+	 * @return
+	 */
+	@JsonIgnore
+	Class<?> getDecoratedClass();
 }