Spring Boot 3 Recipes A Problem-Solution Approach for Java Microservices and Cloud-Native Applications

Table of Contents
About the Author
Introduction
Chapter 1: Introduction to Spring Boot
	1-1. Create a Spring Boot Application Using Maven
		Problem
		Solution
		How It Works
			Create the pom.xml File
			Create the Application Class
	1-2. Create a Spring Boot Application Using Gradle
		Problem
		Solution
		How It Works
			Create the build.gradle File
			Create the Application Class
	1-3. Create a Spring Boot Application Using Spring Initializr
		Problem
		Solution
		How It Works
			Building the JAR File
	Summary
Chapter 2: The Basics of Spring Boot
	2-1. Configure a Bean
		Problem
		Solution
		How It Works
			Configure a Bean Using @Component
			Configure a Bean Using an @Bean Method
	2-2. Externalize Properties
		Problem
		Solution
		How It Works
			Override Properties Using an External application.properties File
			Override Properties Using Profiles
			Override Properties Using Command-Line Arguments
			Load Properties from Different Configuration Files
	2-3. Configure Testing
		Problem
		Solution
		How It Works
			Write a Unit Test
			Mock Dependencies in a Unit Test
			Perform Integration Testing with Spring Boot
			Perform Integration Testing with Spring Boot and Mocks
			Perform Integration Testing with Spring Boot Using Slices
			Use Testcontainers with Spring Boot Testing
	2-4. Configure Logging
		Problem
		Solution
		How It Works
			Configure Logging
			Log to a File
			Use Your Preferred Logging Provider
	2-5. Reuse an Existing Configuration
		Problem
		Solution
		How It Works
			Reuse an Existing XML Configuration
			Reuse an Existing Java Configuration
	2-6. Use Docker with Spring Boot During Development
		Problem
		Solution
		How It Works
			Spring Boot Docker Compose Support
			Spring Boot Docker Compose Support: Custom Container Images
			Spring Boot Testcontainers Support
	2-7. Use Spring Boot Devtools to Speed Up Development
		Problem
		Solution
		How It Works
	Summary
Chapter 3: Spring MVC
	3-1. Get Started with Spring MVC
		Problem
		Solution
		How It Works
			Test the Controller
	3-2. Expose REST Resources with Spring MVC
		Problem
		Solution
		How It Works
			Test an @RestController
	3-3. Use Thymeleaf with Spring Boot
		Problem
		Solution
		How It Works
			Add an Index Page
			Add a Controller and View
			Add a Details Page
			Test an @Controller
	3-4. Handle Exceptions with Spring MVC
		Problem
		Solution
		How It Works
			Handle Exceptions for View Technologies
				Add Attributes to the Model
			Handle Exceptions for REST Controllers
			Enable and Use Problem Details
	3-5. Implement Internationalization (I18N)
		Problem
		Solution
		How It Works
	3-6. Change User Locales
		Problem
		Solution
		How It Works
			Resolve Locales with an HTTP Request Header
			Resolve Locales with a Session Attribute
			Resolve Locales with a Cookie
			Change a User’s Locale
	3-7. Select and Configure the Embedded Server
		Problem
		Solution
		How It Works
			Set General Configuration Properties
			Change the Runtime Container
	3-8. Configure SSL for the Servlet Container
		Problem
		Solution
		How It Works
			Create a Self-Signed Certificate
			Configure Spring Boot to Use the Keystore
			Support Both HTTP and HTTPS
			Redirect HTTP to HTTPS
	3-9. Implement Asynchronous Request Handling with Controllers and TaskExecutor
		Problem
		Solution
		How It Works
			Configure Async Processing
			Write an Asynchronous Controller
			Use a Callable
			Use a CompletableFuture
			Test Async Controllers
	3-10. Create Response Writers
		Problem
		Solution
		How It Works
			Send Multiple Results in a Response
			Send Multiple Results as Events
			Test Server-Sent Events
	3-11. Consume REST Resources with Spring MVC
		Problem
		Solution
		How It Works
			Use a RestTemplate
			Use a RestClient
			Use a Declarative Client
			Test RestTemplate or RestClient-Based Code
Chapter 4: WebFlux
	4-1. Develop a Reactive Application with Spring WebFlux
		Problem
		Solution
		How It Works
			Set Up a Spring WebFlux Application
			Create Spring WebFlux Controllers
			Do Unit Testing for Reactive Controllers
			Do Integration Testing for Reactive Controllers
	4-2. Publish and Consume with Reactive REST Services
		Problem
		Solution
		How It Works
			Stream JSON
			Write an Integration Test
	4-3. Use Thymeleaf as a Template Engine
		Problem
		Solution
		How It Works
			Use Thymeleaf Views
			Make It More Reactive
	4-4. Handle Exceptions with Spring WebFlux
		Problem
		Solution
		How It Works
			Handle Exceptions Handle Exceptions for REST Controllers
			Enable and Use Problem Details
	4-5. Implement Internationalization (I18N)
		Problem
		Solution
		How It Works
	4-6. Change User Locales
		Problem
		Solution
		How It Works
			Resolve Locales with an HTTP Request Header
			Use a Fixed Locale for Your Application
			Change a User’s Locale
	4-7. Select and Configure the Embedded Server
		Problem
		Solution
		How It Works
			Set General Configuration Properties
			Change the Runtime Container
	4-8. Configure SSL for the Reactive Container
		Problem
		Solution
		How It Works
			Create a Self-Signed Certificate
			Configure Spring Boot to Use the Keystore
	4-9. Perform Synchronous Request Handling with Controllers and TaskExecutor
		Problem
		Solution
		How It Works
	4-10. Create Response Writers
		Problem
		Solution
		How It Works
			Send Multiple Results in a Response
			Specify What to Send with Server Send Events
	4-11. Consume REST Resources with Spring WebFlux
		Problem
		Solution
		How It Works
			Use a WebClient
			Use a Declarative Client
Chapter 5: Spring Security
	5-1. Enable Security in Your Spring Boot Application
		Problem
		Solution
		How It Works
			Test the Security
			Perform Integration Testing for Security
	5-2. Log In to Web Applications
		Problem
		Solution
		How It Works
			HTTP Basic Authentication
			Form-Based Login
			The Logout Service
			Anonymous Login
			Remember-Me Support
	5-3. Authenticate Users
		Problem
		Solution
		How It Works
			Authenticate Users with In-Memory Definitions
			Authenticate Users Against a Database
			Authenticate Using OAuth2
			Encrypt Passwords
	5-4. Make Access Control Decisions
		Problem
		Solution
		How It Works
			Use an Expression to Make Access Control Decisions Using Spring Beans
			Secure Methods with Annotations and Expressions
	5-5. Add Security to a WebFlux Application
		Problem
		Solution
		How It Works
			Secure URL Access
			Log in to WebFlux Applications
			Authenticate Users
			Make Access Control Decisions
	Summary
Chapter 6: Data Access
	6-1. Configure a Data Source
		Problem
		Solution
		How It Works
			Use an Embedded Data Source
			Use an External Database
			Obtain a Data Source from JNDI
			Configure the Connection Pool
	6-2. Manage the Database Schema with Spring Boot
		Problem
		Solution
		How It Works
			Initialize the Database with Flyway
	6-3. Use JdbcTemplate or JdbcClient
		Problem
		Solution
		How It Works
			Access JDBC Through JdbcClient
	6-4. Use Spring Data JDBC
		Problem
		Solution
		How It Works
	6-5. Test JDBC Code
		Problem
		Solution
		How It Works
			Test JDBC Code with an Embedded Database
			Test JDBC Code with Testcontainers
			Test Spring Data JDBC Repositories
	6-6. Access Data with JPA
		Problem
		Solution
		How It Works
			Use Plain JPA Repositories
			Use Spring Data JPA Repositories
			Include Entities from Different Packages
	6-7. Test with JPA
		Problem
		Solution
		How It Works
			Test JPA Code with an Embedded Database
			Test JPA Code with Testcontainers
	6-8. Access Spring Data with MongoDB
		Problem
		Solution
		How It Works
			Use the MongoTemplate
			Connect to an External MongoDB
			Use Spring Data MongoDB Repositories
			Use Reactive MongoDB Repositories
			Test Mongo Repositories
			Test MongoDB Code with Testcontainers
	6-9. Access Data with R2DBC
		Problem
		Solution
		How It Works
			Use DatabaseClient
			Use R2dbcEntityTemplate
			Use the R2dbcRepository
	6-10. Test with Spring Data R2DBC
		Problem
		Solution
		How It Works
			Test R2DBC Code with an Embedded Database
			Test Spring Data R2DBC Code with Testcontainers
Chapter 7: Java Enterprise Services
	7-1. Configure Spring Asynchronous Processing
		Problem
		Solution
		How It Works
			Configure the TaskExecutor
	7-2. Configure Spring Task Scheduling
		Problem
		Solution
		How It Works
	7-3. Send Email
		Problem
		Solution
		How It Works
			Configure the JavaMailSender
			Send a Plain-Text Email
			Test the Sending of Email
			Use Thymeleaf for Email Templates
	7-4. Register a JMX MBean
		Problem
		Solution
		How It Works
	7-5. Use Java Flight Recorder to Investigate Application Startup
		Problem
		Solution
		How It Works
			Enable JFR Event Processing
	7-6. Observe Your Application with Micrometer
		Problem
		Solution
			Micrometer Concepts
		How It Works
	Summary
Chapter 8: Spring Messaging
	8-1. Configure JMS
		Problem
		Solution
		How It Works
			Use ActiveMQ
			Use Artemis
			Use Artemis with a Connection Pool
			Use JNDI
			Configure Manually
	8-2. Send Messages Using JMS
		Problem
		Solution
		How It Works
			Send a Message with JmsTemplate
			Configure JmsTemplate
	8-3. Receive Messages Using JMS
		Problem
		Solution
		How It Works
			Receive mMessages
			Configure the Listener Container
			Use a Custom MessageConverter
			Send a Reply
	8-4. Configure RabbitMQ
		Problem
		Solution
		How It Works
	8-5. Send Messages Using RabbitMQ
		Problem
		Solution
		How It Works
			Configure the RabbitTemplate
			Send a Simple Message
			Send an Object
	8-6. Receive Messages Using RabbitMQ
		Problem
		Solution
		How It Works
			Receive a Simple Message
			Receive an Object
			Receive a Message and Send a Reply
	8-7. Configure Spring for Apache Kafka
		Problem
		Solution
		How It Works
	8-8. Send Messages Using Spring Kafka
		Problem
		Solution
		How It Works
			Configure the KafkaTemplate
			Send a Simple Message
			Send an Object
	8-9. Receive Messages Using Kafka
		Problem
		Solution
		How It Works
			Receive a Simple Message
			Receive an Object
			Receive a Message and Send a Reply
	Summary
Chapter 9: Spring Boot Actuator
	9-1. Enable and Configure Spring Boot Actuator
		Problem
		Solution
		How It Works
			Configure the Management Server
			Configure Individual Management Endpoints
			Secure Management Endpoints
			Configure Health Checks
			Configure Metrics
	9-2. Create Custom Health Checks and Metrics
		Problem
		Solution
		How It Works
	9-3. Export Metrics
		Problem
		Solution
		How It Works
	9-4. Tracing with Zipkin
		Problem
		Solution
		How It Works
			Configure Tracing
			Set Up Tracing with an ObservationRegistry
			Set Up Tracing with AspectJ
Chapter 10: Packaging
	10-1. Create an Executable Archive
		Problem
		Solution
		How It Works
			Make the Archive Executable
			Specify the Configuration
	10-2. Create a WAR File for Deployment
		Problem
		Solution
		How It Works
	10-3. Reduce the Archive Size Through the Thin Launcher
		Problem
		Solution
		How It Works
	10-4. Containerize a Spring Boot Application
		Problem
		Solution
		How It Works
			Update a Build Script to Produce a Docker Container
			Build and Start the Container
			Pass Properties to the Spring Boot Application
			Build a Better Docker Container
			Use Buildpacks to Build a Container
	10-5. Use Spring Boot GraalVM Native Images
		Problem
		Solution
			Build a Native Image Using Native Build Tools
			Build a Native Image Using Buildpacks
		How It Works
			Generate Source Code for Bean Definitions
			Generate GraalVM Hints
			Generate Bytecode for Proxy Classes
Index