Minor code changes are the following:

-Removed unused variables from few files.
-Added null assertions in some tests.
-Removed unnecessary throw exceptions.

src/main/java/org/springframework/samples/petclinic/vet/Vet.java

@@ -57,10 +57,6 @@ public class Vet extends Person {
 		return this.specialties;
 	}
 
-	protected void setSpecialtiesInternal(Set<Specialty> specialties) {
-		this.specialties = specialties;
-	}
-
 	@XmlElement
 	public List<Specialty> getSpecialties() {
 		List<Specialty> sortedSpecs = new ArrayList<>(getSpecialtiesInternal());