Created new getRatings endpoint, organized code

src/main/java/sg/com/smartinventory/controllers/ReviewController.java

@@ -16,6 +16,7 @@
 import jakarta.validation.Valid;
 import sg.com.smartinventory.entities.Review;
 import sg.com.smartinventory.services.ReviewService;
+import org.springframework.web.bind.annotation.RequestParam;
 
 @RestController
 @RequestMapping("/reviews")
@@ -44,6 +45,12 @@ public ResponseEntity<Review> getReview(@PathVariable long id) {
         return new ResponseEntity<>(foundReview, HttpStatus.OK);
     }
 
+    // Read (Get ratings)
+    @GetMapping("/ratings")
+    public ArrayList<Review> getRatings(@Valid @RequestParam int rating) {
+        return reviewService.getRatings(rating);
+    }
+
     // UPDATE.
     @PutMapping("/{id}")
     public ResponseEntity<Review> updateReview(@PathVariable long id, @RequestBody Review review) {

src/main/java/sg/com/smartinventory/entities/Review.java

@@ -12,6 +12,7 @@
 import jakarta.persistence.JoinColumn;
 import jakarta.persistence.ManyToOne;
 import jakarta.persistence.Table;
+import jakarta.validation.constraints.Max;
 import jakarta.validation.constraints.Min;
 
 import lombok.AllArgsConstructor;
@@ -38,6 +39,8 @@ public class Review {
   @Column(name = "review_content")
   private String reviewContent;
 
+  @Min(value = 1, message = "Value must be between 1 and 5")
+  @Max(value = 5, message = "Value must be between 1 and 5")
   @Column(name = "rating")
   private int rating;
 

src/main/java/sg/com/smartinventory/exceptions/GlobalExceptionHandler.java

@@ -13,10 +13,12 @@
 
 @ControllerAdvice
 public class GlobalExceptionHandler {
-    // This is handler for CustomerNotFoundException.
+    // This is handler for RuntimeExceptions. Flow: When a client request throws an
+    // exception, SB will find @ControllerAdvice and find the @ExceptionHandler that
+    // contains the Exception thrown.
     @ExceptionHandler({ CustomerNotFoundException.class, ProductNotFoundException.class,
-            ReviewNotFoundException.class })
-    public ResponseEntity<ErrorResponse> handleResourceNotFoundException(CustomerNotFoundException ex) {
+            ReviewNotFoundException.class, RatingNotFoundException.class })
+    public ResponseEntity<ErrorResponse> handleResourceNotFoundException(RuntimeException ex) {
         ErrorResponse errorResponse = new ErrorResponse(ex.getMessage(), LocalDateTime.now());
 
         return new ResponseEntity<>(errorResponse, HttpStatus.NOT_FOUND);

src/main/java/sg/com/smartinventory/exceptions/RatingNotFoundException.java

@@ -0,0 +1,7 @@
+package sg.com.smartinventory.exceptions;
+
+public class RatingNotFoundException extends RuntimeException {
+  public RatingNotFoundException(int rating) {
+    super("No products with rating=" + rating + " found");
+  }
+}

src/main/java/sg/com/smartinventory/repositories/ReviewRepository.java

@@ -13,15 +13,15 @@ public interface ReviewRepository extends JpaRepository<Review, Long> {
     // Custom query to find all reviews with a certain ID.
     // List<Review> findById(long id);
 
+    // Custom query to find all reviews with a certain rating.
+    List<Review> findByRating(int rating);
+
     // Custom query to find all reviews with a certain category.
     List<Review> findByCategory(String category);
 
     // Custom query to find all reviews with a certain review content.
     List<Review> findByReviewContent(String reviewContent);
 
-    // Custom query to find all reviews with a certain rating.
-    List<Review> findByRating(int rating);
-
     // Custom query to find all reviews with a certain customer ID.
     List<Review> findByCustomerId(long customerId);
 

src/main/java/sg/com/smartinventory/serviceImpls/ReviewServiceImpl.java

@@ -2,10 +2,12 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 
 import org.springframework.stereotype.Service;
 
 import sg.com.smartinventory.entities.Review;
+import sg.com.smartinventory.exceptions.RatingNotFoundException;
 import sg.com.smartinventory.exceptions.ReviewNotFoundException;
 import sg.com.smartinventory.repositories.ReviewRepository;
 import sg.com.smartinventory.services.ReviewService;
@@ -19,21 +21,38 @@ public ReviewServiceImpl(ReviewRepository reviewRepository) {
         this.reviewRepository = reviewRepository;
     }
 
+    // - - - POST - - -
     @Override
     public Review createReview(Review review) {
         Review newReview = reviewRepository.save(review);
 
         return newReview;
     }
 
+    // - - - GET - - -
+    @Override
+    public ArrayList<Review> searchCustomerReviews(long customerId) {
+        List<Review> foundReviews = reviewRepository.findByCustomerId(customerId);
+        return (ArrayList<Review>) foundReviews;
+    }
+
+    @Override
+    public ArrayList<Review> searchProductReviews(long productId) {
+        List<Review> foundReviews = reviewRepository.findByProductId(productId);
+        return (ArrayList<Review>) foundReviews;
+    }
+
+    @Override
+    public ArrayList<Review> getRatings(int id) {
+        if (reviewRepository.findByRating(id).isEmpty()) {
+            throw new RatingNotFoundException(id);
+        }
+        List<Review> reviews = reviewRepository.findByRating(id);
+        return (ArrayList<Review>) reviews;
+    }
+
     @Override
     public Review getReview(Long id) {
-        // Optional<Review> optionalReview = reviewRepository.findById(id);
-        // if(optionalReview.isPresent()) {
-        // Review foundReview = optionalReview.get();
-        // return foundReview;
-        // }
-        // throw new ReviewNotFoundException(id);
         return reviewRepository.findById(id).orElseThrow(() -> new ReviewNotFoundException(id));
     }
 
@@ -43,6 +62,7 @@ public ArrayList<Review> getAllReviews() {
         return (ArrayList<Review>) allReviews;
     }
 
+    // - - - PUT - - -
     @Override
     public Review updateReview(Long id, Review review) {
         // Retrieve the review from the database.
@@ -58,20 +78,9 @@ public Review updateReview(Long id, Review review) {
         return reviewRepository.save(reviewToUpdate);
     }
 
+    // - - - DELETE - - -
     @Override
     public void deleteReview(long id) {
         reviewRepository.deleteById(id);
     }
-
-    @Override
-    public ArrayList<Review> searchCustomerReviews(long customerId) {
-        List<Review> foundReviews = reviewRepository.findByCustomerId(customerId);
-        return (ArrayList<Review>) foundReviews;
-    }
-
-    @Override
-    public ArrayList<Review> searchProductReviews(long productId) {
-        List<Review> foundReviews = reviewRepository.findByProductId(productId);
-        return (ArrayList<Review>) foundReviews;
-    }
 }

src/main/java/sg/com/smartinventory/services/ReviewService.java

@@ -18,4 +18,6 @@ public interface ReviewService {
     ArrayList<Review> searchCustomerReviews(long customerId);
 
     ArrayList<Review> searchProductReviews(long productId);
+
+    ArrayList<Review> getRatings(int rating);
 }