DATAJPA-1064 - Add null guard for Optional (we actually should not need it).

However EntityManagerFactoryRefTests fail on cmd line when removing it though everything works fine when running tests from ide - strange things happen.

Author: christophstrobl

src/main/java/org/springframework/data/jpa/domain/AbstractAuditable.java

@@ -72,7 +72,8 @@ public Optional<U> getCreatedBy() {
 	 */
 	public void setCreatedBy(final Optional<? extends U> createdBy) {
 
-		this.createdBy = createdBy.orElse(null);
+		// TODO: this null guard should really not be required since we expect an optional here
+		this.createdBy = createdBy != null ? createdBy.orElse(null) : null;
 	}
 
 	/*
@@ -117,7 +118,8 @@ public Optional<U> getLastModifiedBy() {
 	 */
 	public void setLastModifiedBy(final Optional<? extends U> lastModifiedBy) {
 
-		this.lastModifiedBy = lastModifiedBy.orElse(null);
+		// TODO: this null guard should really not be required since we expect an optional here
+		this.lastModifiedBy = lastModifiedBy != null ? lastModifiedBy.orElse(null) : null;
 	}
 
 	/*