deps: Refactor dependencies (#3224)

* remove spring dep
move junit, logging, mockito under dep mgmt

* upgrade anti-corruption-layer deps

* async method invocation

* balking, bloc

* bridge to bytecode

* caching

* callback - cqrs

* component - health check

* hexagonal - metadata mapping

* rest of the patterns

* remove checkstyle, take spotless into use

microservices-distributed-tracing/order-microservice/src/main/java/com/iluwatar/order/microservice/Main.java

@@ -52,10 +52,9 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  * {@code docker run -d -p 9411:9411 --name zipkin openzipkin/zipkin }
  * </pre>
  *
- * <p>Start Zipkin with the command above. Once Zipkin is running, you can
- * access the Zipkin UI at `<a href="http://localhost:9411">...</a>`
- * to view the tracing logs and analyze the request flows across your microservices.
- *
+ * <p>Start Zipkin with the command above. Once Zipkin is running, you can access the Zipkin UI at
+ * `<a href="http://localhost:9411">...</a>` to view the tracing logs and analyze the request flows
+ * across your microservices.
  *
  * <p>To place an order and generate tracing data, you can use the following curl command:
  *
@@ -65,7 +64,6 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  *
  * <p>This command sends a POST request to create an order, which will trigger interactions with the
  * payment and product microservices, generating tracing logs that can be viewed in Zipkin.
- *
  */
 @SpringBootApplication
 public class Main {

microservices-distributed-tracing/order-microservice/src/main/java/com/iluwatar/order/microservice/OrderController.java

@@ -30,9 +30,7 @@ import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RestController;
 
-/**
- * This controller handles order processing by calling necessary microservices.
- */
+/** This controller handles order processing by calling necessary microservices. */
 @Slf4j
 @RestController
 public class OrderController {

microservices-distributed-tracing/order-microservice/src/main/java/com/iluwatar/order/microservice/OrderService.java

@@ -31,9 +31,7 @@ import org.springframework.stereotype.Service;
 import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.ResourceAccessException;
 
-/**
- * Service to handle order processing logic.
- */
+/** Service to handle order processing logic. */
 @Slf4j
 @Service
 public class OrderService {
@@ -50,9 +48,8 @@ public class OrderService {
   }
 
   /**
-   * Processes an order by calling
-   * {@link OrderService#validateProduct()} and
-   * {@link OrderService#processPayment()}.
+   * Processes an order by calling {@link OrderService#validateProduct()} and {@link
+   * OrderService#processPayment()}.
    *
    * @return A string indicating whether the order was processed successfully or failed.
    */
@@ -70,10 +67,11 @@ public class OrderService {
    */
   Boolean validateProduct() {
     try {
-      ResponseEntity<Boolean> productValidationResult = restTemplateBuilder
-          .build()
-          .postForEntity("http://localhost:30302/product/validate", "validating product",
-              Boolean.class);
+      ResponseEntity<Boolean> productValidationResult =
+          restTemplateBuilder
+              .build()
+              .postForEntity(
+                  "http://localhost:30302/product/validate", "validating product", Boolean.class);
       LOGGER.info("Product validation result: {}", productValidationResult.getBody());
       return productValidationResult.getBody();
     } catch (ResourceAccessException | HttpClientErrorException e) {
@@ -89,10 +87,11 @@ public class OrderService {
    */
   Boolean processPayment() {
     try {
-      ResponseEntity<Boolean> paymentProcessResult = restTemplateBuilder
-          .build()
-          .postForEntity("http://localhost:30301/payment/process", "processing payment",
-              Boolean.class);
+      ResponseEntity<Boolean> paymentProcessResult =
+          restTemplateBuilder
+              .build()
+              .postForEntity(
+                  "http://localhost:30301/payment/process", "processing payment", Boolean.class);
       LOGGER.info("Payment processing result: {}", paymentProcessResult.getBody());
       return paymentProcessResult.getBody();
     } catch (ResourceAccessException | HttpClientErrorException e) {

microservices-distributed-tracing/order-microservice/src/test/java/com/iluwatar/order/microservice/MainTest.java

@@ -28,12 +28,10 @@ import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 import org.junit.jupiter.api.Test;
 
-/**
- * Application test
- */
+/** Application test */
 class MainTest {
   @Test
   void shouldExecuteApplicationWithoutException() {
-    assertDoesNotThrow(() -> Main.main(new String[]{}));
+    assertDoesNotThrow(() -> Main.main(new String[] {}));
   }
 }

microservices-distributed-tracing/order-microservice/src/test/java/com/iluwatar/order/microservice/OrderControllerTest.java

@@ -1,27 +1,31 @@
-package com.iluwatar.order.microservice;/*
- * This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
- *
- * The MIT License
- * Copyright © 2014-2022 Ilkka Seppälä
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
+package com.iluwatar.order.microservice; /*
+                                          * This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
+                                          *
+                                          * The MIT License
+                                          * Copyright © 2014-2022 Ilkka Seppälä
+                                          *
+                                          * Permission is hereby granted, free of charge, to any person obtaining a copy
+                                          * of this software and associated documentation files (the "Software"), to deal
+                                          * in the Software without restriction, including without limitation the rights
+                                          * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+                                          * copies of the Software, and to permit persons to whom the Software is
+                                          * furnished to do so, subject to the following conditions:
+                                          *
+                                          * The above copyright notice and this permission notice shall be included in
+                                          * all copies or substantial portions of the Software.
+                                          *
+                                          * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+                                          * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+                                          * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+                                          * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+                                          * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+                                          * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+                                          * THE SOFTWARE.
+                                          */
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.when;
+
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.InjectMocks;
@@ -29,28 +33,19 @@ import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 import org.springframework.http.ResponseEntity;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.mockito.Mockito.when;
-
-/**
- * OrderControllerTest class to test the OrderController.
- */
+/** OrderControllerTest class to test the OrderController. */
 class OrderControllerTest {
 
-  @InjectMocks
-  private OrderController orderController;
+  @InjectMocks private OrderController orderController;
 
-  @Mock
-  private OrderService orderService;
+  @Mock private OrderService orderService;
 
   @BeforeEach
   void setup() {
     MockitoAnnotations.openMocks(this);
   }
 
-  /**
-   * Test to process the order successfully.
-   */
+  /** Test to process the order successfully. */
   @Test
   void processOrderShouldReturnSuccessStatus() {
     // Arrange
@@ -61,9 +56,7 @@ class OrderControllerTest {
     assertEquals("Order processed successfully", response.getBody());
   }
 
-  /**
-   * Test to process the order with failure.
-   */
+  /** Test to process the order with failure. */
   @Test
   void ProcessOrderShouldReturnFailureStatusWhen() {
     // Arrange

microservices-distributed-tracing/order-microservice/src/test/java/com/iluwatar/order/microservice/OrderServiceTest.java

@@ -36,23 +36,18 @@ import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 import org.springframework.boot.web.client.RestTemplateBuilder;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.ResourceAccessException;
+import org.springframework.web.client.RestTemplate;
 
-/**
- * OrderServiceTest class to test the OrderService.
- */
+/** OrderServiceTest class to test the OrderService. */
 class OrderServiceTest {
 
-  @InjectMocks
-  private OrderService orderService;
+  @InjectMocks private OrderService orderService;
 
-  @Mock
-  private RestTemplateBuilder restTemplateBuilder;
+  @Mock private RestTemplateBuilder restTemplateBuilder;
 
-  @Mock
-  private RestTemplate restTemplate;
+  @Mock private RestTemplate restTemplate;
 
   @BeforeEach
   void setup() {
@@ -60,15 +55,15 @@ class OrderServiceTest {
     when(restTemplateBuilder.build()).thenReturn(restTemplate);
   }
 
-  /**
-   * Test to process the order successfully.
-   */
+  /** Test to process the order successfully. */
   @Test
   void testProcessOrder_Success() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
         .thenReturn(ResponseEntity.ok(true));
-    when(restTemplate.postForEntity(eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
         .thenReturn(ResponseEntity.ok(true));
     // Act
     String result = orderService.processOrder();
@@ -76,13 +71,12 @@ class OrderServiceTest {
     assertEquals("Order processed successfully", result);
   }
 
-  /**
-   * Test to process the order with failure caused by product validation failure.
-   */
+  /** Test to process the order with failure caused by product validation failure. */
   @Test
   void testProcessOrder_FailureWithProductValidationFailure() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
         .thenReturn(ResponseEntity.ok(false));
     // Act
     String result = orderService.processOrder();
@@ -90,15 +84,15 @@ class OrderServiceTest {
     assertEquals("Order processing failed", result);
   }
 
-  /**
-   * Test to process the order with failure caused by payment processing failure.
-   */
+  /** Test to process the order with failure caused by payment processing failure. */
   @Test
   void testProcessOrder_FailureWithPaymentProcessingFailure() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
         .thenReturn(ResponseEntity.ok(true));
-    when(restTemplate.postForEntity(eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
         .thenReturn(ResponseEntity.ok(false));
     // Act
     String result = orderService.processOrder();
@@ -106,13 +100,12 @@ class OrderServiceTest {
     assertEquals("Order processing failed", result);
   }
 
-  /**
-   * Test to validate the product.
-   */
+  /** Test to validate the product. */
   @Test
   void testValidateProduct() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
         .thenReturn(ResponseEntity.ok(true));
     // Act
     Boolean result = orderService.validateProduct();
@@ -120,13 +113,12 @@ class OrderServiceTest {
     assertEquals(true, result);
   }
 
-  /**
-   * Test to process the payment.
-   */
+  /** Test to process the payment. */
   @Test
   void testProcessPayment() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
         .thenReturn(ResponseEntity.ok(true));
     // Act
     Boolean result = orderService.processPayment();
@@ -134,13 +126,12 @@ class OrderServiceTest {
     assertEquals(true, result);
   }
 
-  /**
-   * Test to validate the product with ResourceAccessException.
-   */
+  /** Test to validate the product with ResourceAccessException. */
   @Test
   void testValidateProduct_ResourceAccessException() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
         .thenThrow(new ResourceAccessException("Service unavailable"));
     // Act
     Boolean result = orderService.validateProduct();
@@ -148,27 +139,27 @@ class OrderServiceTest {
     assertEquals(false, result);
   }
 
-  /**
-   * Test to validate the product with HttpClientErrorException.
-   */
+  /** Test to validate the product with HttpClientErrorException. */
   @Test
   void testValidateProduct_HttpClientErrorException() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
-        .thenThrow(new HttpClientErrorException(org.springframework.http.HttpStatus.BAD_REQUEST, "Bad request"));
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30302/product/validate"), anyString(), eq(Boolean.class)))
+        .thenThrow(
+            new HttpClientErrorException(
+                org.springframework.http.HttpStatus.BAD_REQUEST, "Bad request"));
     // Act
     Boolean result = orderService.validateProduct();
     // Assert
     assertEquals(false, result);
   }
 
-  /**
-   * Test to process the payment with ResourceAccessException.
-   */
+  /** Test to process the payment with ResourceAccessException. */
   @Test
   void testProcessPayment_ResourceAccessException() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
         .thenThrow(new ResourceAccessException("Service unavailable"));
     // Act
     Boolean result = orderService.processPayment();
@@ -176,14 +167,15 @@ class OrderServiceTest {
     assertEquals(false, result);
   }
 
-  /**
-   * Test to process the payment with HttpClientErrorException.
-   */
+  /** Test to process the payment with HttpClientErrorException. */
   @Test
   void testProcessPayment_HttpClientErrorException() {
     // Arrange
-    when(restTemplate.postForEntity(eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
-        .thenThrow(new HttpClientErrorException(org.springframework.http.HttpStatus.BAD_REQUEST, "Bad request"));
+    when(restTemplate.postForEntity(
+            eq("http://localhost:30301/payment/process"), anyString(), eq(Boolean.class)))
+        .thenThrow(
+            new HttpClientErrorException(
+                org.springframework.http.HttpStatus.BAD_REQUEST, "Bad request"));
     // Act
     Boolean result = orderService.processPayment();
     // Assert

microservices-distributed-tracing/payment-microservice/src/main/java/com/iluwatar/payment/microservice/Main.java

@@ -41,10 +41,9 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  * journey.
  *
  * <p>This implementation demonstrates distributed tracing in a microservices architecture for an
- * e-commerce platform. When a customer places an order, the OrderService interacts with
- * both the PaymentService to process the payment and the ProductService to check the
- * product inventory. Tracing logs are generated for each interaction, and these logs can be
- * visualized using Zipkin.
+ * e-commerce platform. When a customer places an order, the OrderService interacts with both the
+ * PaymentService to process the payment and the ProductService to check the product inventory.
+ * Tracing logs are generated for each interaction, and these logs can be visualized using Zipkin.
  *
  * <p>To run Zipkin and view the tracing logs, you can use the following Docker command:
  *
@@ -52,9 +51,9 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  * {@code docker run -d -p 9411:9411 --name zipkin openzipkin/zipkin }
  * </pre>
  *
- * <p>Start Zipkin with the command above. Once Zipkin is running, you can
- * access the Zipkin UI at <a href="http://localhost:9411">http://localhost:9411</a>
- * to view the tracing logs and analyze the request flows across your microservices.
+ * <p>Start Zipkin with the command above. Once Zipkin is running, you can access the Zipkin UI at
+ * <a href="http://localhost:9411">http://localhost:9411</a> to view the tracing logs and analyze
+ * the request flows across your microservices.
  *
  * <p>To place an order and generate tracing data, you can use the following curl command:
  *
@@ -64,7 +63,6 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  *
  * <p>This command sends a POST request to create an order, which will trigger interactions with the
  * payment and product microservices, generating tracing logs that can be viewed in Zipkin.
- *
  */
 @SpringBootApplication
 public class Main {

microservices-distributed-tracing/payment-microservice/src/main/java/com/iluwatar/payment/microservice/PaymentController.java

@@ -30,9 +30,7 @@ import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RestController;
 
-/**
- * Controller for handling payment processing requests.
- */
+/** Controller for handling payment processing requests. */
 @Slf4j
 @RestController
 public class PaymentController {

microservices-distributed-tracing/payment-microservice/src/test/java/com/iluwatar/payment/microservice/MainTest.java

@@ -24,16 +24,14 @@
  */
 package com.iluwatar.payment.microservice;
 
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
-/**
- * Application Context loads test
- */
+import org.junit.jupiter.api.Test;
+
+/** Application Context loads test */
 class MainTest {
   @Test
   void shouldExecuteApplicationWithoutException() {
-    assertDoesNotThrow(() -> Main.main(new String[]{}));
+    assertDoesNotThrow(() -> Main.main(new String[] {}));
   }
 }

microservices-distributed-tracing/payment-microservice/src/test/java/com/iluwatar/payment/microservice/ProductControllerTest.java

@@ -24,15 +24,13 @@
  */
 package com.iluwatar.payment.microservice;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.springframework.http.ResponseEntity;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
-/**
- * Payment controller test.
- */
+/** Payment controller test. */
 class ProductControllerTest {
 
   private PaymentController paymentController;
@@ -41,9 +39,8 @@ class ProductControllerTest {
   void setUp() {
     paymentController = new PaymentController();
   }
-  /**
-   * Test to process the payment.
-   */
+
+  /** Test to process the payment. */
   @Test
   void testValidateProduct() {
     // Arrange
@@ -54,9 +51,7 @@ class ProductControllerTest {
     assertEquals(ResponseEntity.ok(true), response);
   }
 
-  /**
-   * Test to process the payment with null request.
-   */
+  /** Test to process the payment with null request. */
   @Test
   void testValidateProductWithNullRequest() {
     // Arrange

microservices-distributed-tracing/pom.xml

@@ -34,17 +34,6 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>microservices-distributed-tracing</artifactId>
     <packaging>pom</packaging>
-    <dependencyManagement>
-        <dependencies>
-            <dependency>
-                <groupId>org.springframework.boot</groupId>
-                <artifactId>spring-boot-dependencies</artifactId>
-                <type>pom</type>
-                <version>3.3.1</version>
-                <scope>import</scope>
-            </dependency>
-        </dependencies>
-    </dependencyManagement>
     <dependencies>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -57,11 +46,13 @@
         <dependency>
             <groupId>io.micrometer</groupId>
             <artifactId>micrometer-tracing-bridge-brave</artifactId>
+            <version>1.4.4</version>
             <scope>compile</scope>
         </dependency>
         <dependency>
             <groupId>io.zipkin.reporter2</groupId>
             <artifactId>zipkin-reporter-brave</artifactId>
+            <version>3.5.0</version>
         </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>

microservices-distributed-tracing/product-microservice/src/main/java/com/iluwatar/product/microservice/microservice/Main.java

@@ -41,10 +41,9 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  * journey.
  *
  * <p>This implementation demonstrates distributed tracing in a microservices architecture for an
- * e-commerce platform. When a customer places an order, the OrderService interacts with
- * both the PaymentService to process the payment and the ProductService to check the
- * product inventory. Tracing logs are generated for each interaction, and these logs can be
- * visualized using Zipkin.
+ * e-commerce platform. When a customer places an order, the OrderService interacts with both the
+ * PaymentService to process the payment and the ProductService to check the product inventory.
+ * Tracing logs are generated for each interaction, and these logs can be visualized using Zipkin.
  *
  * <p>To run Zipkin and view the tracing logs, you can use the following Docker command:
  *
@@ -52,9 +51,9 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  * {@code docker run -d -p 9411:9411 --name zipkin openzipkin/zipkin }
  * </pre>
  *
- * <p>Start Zipkin with the command above. Once Zipkin is running, you can
- * access the Zipkin UI at <a href="http://localhost:9411">http://localhost:9411</a>
- * to view the tracing logs and analyze the request flows across your microservices.
+ * <p>Start Zipkin with the command above. Once Zipkin is running, you can access the Zipkin UI at
+ * <a href="http://localhost:9411">http://localhost:9411</a> to view the tracing logs and analyze
+ * the request flows across your microservices.
  *
  * <p>To place an order and generate tracing data, you can use the following curl command:
  *
@@ -64,7 +63,6 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  *
  * <p>This command sends a POST request to create an order, which will trigger interactions with the
  * payment and product microservices, generating tracing logs that can be viewed in Zipkin.
- *
  */
 @SpringBootApplication
 public class Main {

microservices-distributed-tracing/product-microservice/src/main/java/com/iluwatar/product/microservice/microservice/ProductController.java

@@ -30,9 +30,7 @@ import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RestController;
 
-/**
- * Controller for handling product validation requests.
- */
+/** Controller for handling product validation requests. */
 @Slf4j
 @RestController
 public class ProductController {

microservices-distributed-tracing/product-microservice/src/test/java/com/iluwatar/product/microservice/MainTest.java

@@ -24,17 +24,15 @@
  */
 package com.iluwatar.product.microservice;
 
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
 import com.iluwatar.product.microservice.microservice.Main;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
-
-/**
- * Application test
- */
+/** Application test */
 class MainTest {
   @Test
   void shouldExecuteApplicationWithoutException() {
-    assertDoesNotThrow(() -> Main.main(new String[]{}));
+    assertDoesNotThrow(() -> Main.main(new String[] {}));
   }
 }

microservices-distributed-tracing/product-microservice/src/test/java/com/iluwatar/product/microservice/ProductControllerTest.java

@@ -24,14 +24,13 @@
  */
 package com.iluwatar.product.microservice;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import com.iluwatar.product.microservice.microservice.ProductController;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.springframework.http.ResponseEntity;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
-
 class ProductControllerTest {
 
   private ProductController productController;
@@ -41,9 +40,7 @@ class ProductControllerTest {
     productController = new ProductController();
   }
 
-  /**
-   * Test to validate the product.
-   */
+  /** Test to validate the product. */
   @Test
   void testValidateProduct() {
     // Arrange
@@ -54,9 +51,7 @@ class ProductControllerTest {
     assertEquals(ResponseEntity.ok(true), response);
   }
 
-  /**
-   * Test to validate the product with null request.
-   */
+  /** Test to validate the product with null request. */
   @Test
   void testValidateProductWithNullRequest() {
     // Arrange