Improved Validation for Birth Dates AND Duplicate Pet Name Check Enhancement:

src/main/java/org/springframework/samples/petclinic/owner/PetController.java

@@ -1,18 +1,3 @@
-/*
- * Copyright 2012-2019 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
 package org.springframework.samples.petclinic.owner;
 
 import java.time.LocalDate;
@@ -33,11 +18,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import jakarta.validation.Valid;
 import org.springframework.web.servlet.mvc.support.RedirectAttributes;
 
-/**
- * @author Juergen Hoeller
- * @author Ken Krebs
- * @author Arjen Poutsma
- */
 @Controller
 @RequestMapping("/owners/{ownerId}")
 class PetController {
@@ -57,7 +37,6 @@ class PetController {
 
     @ModelAttribute("owner")
     public Owner findOwner(@PathVariable("ownerId") int ownerId) {
-
         Owner owner = this.owners.findById(ownerId);
         if (owner == null) {
             throw new IllegalArgumentException("Owner ID not found: " + ownerId);
@@ -68,11 +47,9 @@ class PetController {
     @ModelAttribute("pet")
     public Pet findPet(@PathVariable("ownerId") int ownerId,
                        @PathVariable(name = "petId", required = false) Integer petId) {
-
         if (petId == null) {
             return new Pet();
         }
-
         Owner owner = this.owners.findById(ownerId);
         if (owner == null) {
             throw new IllegalArgumentException("Owner ID not found: " + ownerId);
@@ -101,30 +78,25 @@ class PetController {
     @PostMapping("/pets/new")
     public String processCreationForm(Owner owner, @Valid Pet pet, BindingResult result, ModelMap model,
                                        RedirectAttributes redirectAttributes) {
-		if (StringUtils.hasText(pet.getName()) && pet.isNew() && owner.getPet(pet.getName(), true) != null) {
+        validatePetNameAndBirthDate(owner, pet, result);
-			result.rejectValue("name", "duplicate", "already exists");
-		}
 
-		LocalDate currentDate = LocalDate.now();
-		if (pet.getBirthDate() != null && pet.getBirthDate().isAfter(currentDate)) {
-			result.rejectValue("birthDate", "typeMismatch.birthDate");
-		}
-
-		owner.addPet(pet);
         if (result.hasErrors()) {
             model.put("pet", pet);
             return VIEWS_PETS_CREATE_OR_UPDATE_FORM;
         }
 
+        owner.addPet(pet);
         this.owners.save(owner);
         redirectAttributes.addFlashAttribute("message", "New Pet has been Added");
         return "redirect:/owners/{ownerId}";
     }
 
     @GetMapping("/pets/{petId}/edit")
-	public String initUpdateForm(Owner owner, @PathVariable("petId") int petId, ModelMap model,
+    public String initUpdateForm(Owner owner, @PathVariable("petId") int petId, ModelMap model) {
-			RedirectAttributes redirectAttributes) {
         Pet pet = owner.getPet(petId);
+        if (pet == null) {
+            throw new IllegalArgumentException("Pet ID not found: " + petId);
+        }
         model.put("pet", pet);
         return VIEWS_PETS_CREATE_OR_UPDATE_FORM;
     }
@@ -132,21 +104,7 @@ class PetController {
     @PostMapping("/pets/{petId}/edit")
     public String processUpdateForm(@Valid Pet pet, BindingResult result, Owner owner, ModelMap model,
                                      RedirectAttributes redirectAttributes) {
-
+        validatePetNameAndBirthDate(owner, pet, result);
-		String petName = pet.getName();
-
-		// checking if the pet name already exist for the owner
-		if (StringUtils.hasText(petName)) {
-			Pet existingPet = owner.getPet(petName.toLowerCase(), false);
-			if (existingPet != null && existingPet.getId() != pet.getId()) {
-				result.rejectValue("name", "duplicate", "already exists");
-			}
-		}
-
-		LocalDate currentDate = LocalDate.now();
-		if (pet.getBirthDate() != null && pet.getBirthDate().isAfter(currentDate)) {
-			result.rejectValue("birthDate", "typeMismatch.birthDate");
-		}
 
         if (result.hasErrors()) {
             model.put("pet", pet);
@@ -155,8 +113,21 @@ class PetController {
 
         owner.addPet(pet);
         this.owners.save(owner);
-		redirectAttributes.addFlashAttribute("message", "Pet details has been edited");
+        redirectAttributes.addFlashAttribute("message", "Pet details have been edited");
         return "redirect:/owners/{ownerId}";
     }
 
+    private void validatePetNameAndBirthDate(Owner owner, Pet pet, BindingResult result) {
+        String petName = pet.getName();
+
+        // Checking if the pet name already exists for the owner
+        if (StringUtils.hasText(petName) && owner.getPet(petName, true) != null) {
+            result.rejectValue("name", "duplicate", "already exists");
+        }
+
+        LocalDate currentDate = LocalDate.now();
+        if (pet.getBirthDate() == null || pet.getBirthDate().isAfter(currentDate)) {
+            result.rejectValue("birthDate", "typeMismatch.birthDate");
+        }
+    }
 }