add Exceptions package

kbazaar/src/main/java/com/kampus/kbazaar/exceptions/ApiErrorResponse.java

@@ -0,0 +1,59 @@
+package com.kampus.kbazaar.exceptions;
+
+import java.time.LocalDateTime;
+
+public class ApiErrorResponse {
+    private LocalDateTime timestamp;
+    private int status;
+    private String error;
+    private String message;
+    private String path;
+
+    public ApiErrorResponse(LocalDateTime timestamp, int status, String error, String message, String path) {
+        this.timestamp = timestamp;
+        this.status = status;
+        this.error = error;
+        this.message = message;
+        this.path = path;
+    }
+
+    public LocalDateTime getTimestamp() {
+        return timestamp;
+    }
+
+    public void setTimestamp(LocalDateTime timestamp) {
+        this.timestamp = timestamp;
+    }
+
+    public int getStatus() {
+        return status;
+    }
+
+    public void setStatus(int status) {
+        this.status = status;
+    }
+
+    public String getError() {
+        return error;
+    }
+
+    public void setError(String error) {
+        this.error = error;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+
+    public String getPath() {
+        return path;
+    }
+
+    public void setPath(String path) {
+        this.path = path;
+    }
+}

kbazaar/src/main/java/com/kampus/kbazaar/exceptions/ControllerExceptionHandler.java

@@ -0,0 +1,56 @@
+package com.kampus.kbazaar.exceptions;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.MethodArgumentNotValidException;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.ResponseStatus;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+import org.springframework.web.context.request.WebRequest;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+@RestControllerAdvice
+public class ControllerExceptionHandler {
+
+    @ExceptionHandler(value = {MethodArgumentNotValidException.class})
+    @ResponseStatus(HttpStatus.BAD_REQUEST)
+    public ApiErrorResponse handleBadRequestException(MethodArgumentNotValidException notValidException, WebRequest request) {
+        List<String> error = notValidException.getFieldErrors()
+                .stream()
+                .map(f -> f.getField()  + " " + f.getDefaultMessage())
+                .toList();
+
+        return new ApiErrorResponse(
+              LocalDateTime.now(),
+                HttpStatus.BAD_REQUEST.value(),
+                HttpStatus.BAD_REQUEST.getReasonPhrase(),
+                String.join(", ", error),
+                request.getDescription(false)
+        );
+    }
+
+    @ExceptionHandler(value = {NotFoundException.class})
+    @ResponseStatus(HttpStatus.NOT_FOUND)
+    public ApiErrorResponse handleNotFoundRequestException(NotFoundException notValidException, WebRequest request) {
+        return new ApiErrorResponse(
+                LocalDateTime.now(),
+                HttpStatus.NOT_FOUND.value(),
+                HttpStatus.NOT_FOUND.getReasonPhrase(),
+                notValidException.getMessage(),
+                request.getDescription(false)
+        );
+    }
+
+    @ExceptionHandler(value = {InternalServerException.class})
+    @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
+    public ApiErrorResponse handleInternalServerException(InternalServerException internalServerException, WebRequest request) {
+        return new ApiErrorResponse(
+                LocalDateTime.now(),
+                HttpStatus.INTERNAL_SERVER_ERROR.value(),
+                HttpStatus.INTERNAL_SERVER_ERROR.getReasonPhrase(),
+                internalServerException.getMessage(),
+                request.getDescription(false)
+        );
+    }
+}

kbazaar/src/main/java/com/kampus/kbazaar/exceptions/InternalServerException.java

@@ -0,0 +1,7 @@
+package com.kampus.kbazaar.exceptions;
+
+public class InternalServerException extends RuntimeException {
+    public InternalServerException(String message) {
+        super(message);
+    }
+}

kbazaar/src/main/java/com/kampus/kbazaar/exceptions/NotFoundException.java

@@ -0,0 +1,7 @@
+package com.kampus.kbazaar.exceptions;
+
+public class NotFoundException extends RuntimeException {
+    public NotFoundException(String message) {
+        super(message);
+    }
+}

kbazaar/src/main/java/com/kampus/kbazaar/product/ProductService.java

@@ -2,6 +2,8 @@
 
 import java.util.List;
 import java.util.Optional;
+
+import com.kampus.kbazaar.exceptions.NotFoundException;
 import org.springframework.stereotype.Service;
 
 @Service
@@ -29,9 +31,7 @@ public List<ProductResponse> getAll() {
     public ProductResponse getBySku(String sku) {
         Optional<Product> product = productRepository.findBySku(sku);
         if (product.isEmpty()) {
-            //            throw new ProductNotFoundException("Product not found");
-            //            TODO: handle exception
-            return null;
+            throw new NotFoundException("Product not found");
         }
 
         return product.get().toResponse();