Make fields private where possible

spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/HotelSummary.java

@@ -28,13 +28,13 @@ public class HotelSummary implements Serializable {
 	private static final MathContext MATH_CONTEXT = new MathContext(2,
 			RoundingMode.HALF_UP);
 
-	private City city;
+	private final City city;
 
-	private String name;
+	private final String name;
 
-	private Double averageRating;
+	private final Double averageRating;
 
-	private Integer averageRatingRounded;
+	private final Integer averageRatingRounded;
 
 	public HotelSummary(City city, String name, Double averageRating) {
 		this.city = city;

spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/domain/RatingCount.java

@@ -22,9 +22,9 @@ public class RatingCount implements Serializable {
 
 	private static final long serialVersionUID = 1L;
 
-	private Rating rating;
+	private final Rating rating;
 
-	private long count;
+	private final long count;
 
 	public RatingCount(Rating rating, long count) {
 		this.rating = rating;

spring-boot-samples/spring-boot-sample-data-jpa/src/main/java/sample/data/jpa/service/HotelServiceImpl.java

@@ -82,7 +82,7 @@ class HotelServiceImpl implements HotelService {
 
 	private static class ReviewsSummaryImpl implements ReviewsSummary {
 
-		private Map<Rating, Long> ratingCount;
+		private final Map<Rating, Long> ratingCount;
 
 		public ReviewsSummaryImpl(List<RatingCount> ratingCounts) {
 			this.ratingCount = new HashMap<Rating, Long>();