Learn to configure and use different DataSource in different environments (test, development, production etc.) using the Spring profile specific properties files, as well as Java configuration in a Spring boot application. 1. Introduction A production grade application is deployed and tested in different environments before finally released to the end-user. …
Learn to perform integration testing using Testcontainers and JUnit 5 in a Spring boot application, including creating a @ServiceConnection.
Learn to create Spring boot API to handle MultipartFile request to upload files and invoking such API from the Angular using example.
Learn to use Spring PartEvent API for streaming multipart requests to a webflux controller and handle the form parameters and file contents.
Learn to configure and deploy a Spring Boot application as a traditional .war file into an external tomcat application server.
Since version 6, Spring supports creating an RSocket service as a Java interface with @RSocketExchange annotated methods for TCP exchanges.
Learn the RSocket protocol and implement communication models in Spring boot using reactive types such as Mono and Flux with examples.
Learn how to enable SQL logging in a Spring boot Data JPA application, print SQL statements and prepare statements with parameter values.
Learn to configure MyBatis with Spring Boot 3 and configure @Mapper and DataSource. Also, learn mapper scanning with @MapperScan with example.
Learn the core concepts of GraphQL and running an example Spring Boot application with GraphQL integrated for querying and updating the data.
This JHipster tutorial will familiarize you with this popular code generation platform and work with front-end and backend generated code.
In this Spring boot with Angular tutorial, learn to create REST APIs using Spring boot and call from Angular to create a CRUD application.
Spring Boot Gradle plugin provides support for Spring Boot applications using Gradle as the build automation tool that helps in dependency management and application packaging.
Springdoc OpenAPI generates the OpenAPI 3 document and the Swagger UI page for a Spring Boot REST API from one starter dependency. Default URLs, springdoc.* properties, Swagger annotations, groups, security scheme and how to switch the docs off in production.
Learn different ways to configure a Spring Boot non-web application that starts without an embedded Web server such as tomcat or jetty.
Learn about the new features and changes introduced in Spring 6 and Spring boot 3 such as baseline upgrade to Java 17 and removing all deprecated classes, methods and properties.
Learn about Caffeine Cache and how we can use Caffeine with Spring Boot. Learn to configure caching, add and evict cache entries with example
In this Spring boot tutorial, we will learn to create, order and register servlet filters in different ways including Filter interface, @WebFilter annotation and inbuilt filter bean classes. 1. Introduction In a web application, we must implement the javax.servlet.Filter interface (jakarta.servlet.Filter in Spring Boot 3) to create filters that can …
Learn about Spring Boot Actuator and adding custom static and dynamic information to the /info endpoint using properties and InfoContributor.
Apache Cassandra is a distributed database system. This guide walks through the process of using Spring Data Cassandra with Spring Boot.
Learn Spring Boot with the following in-depth tutorials, covering from basic to advanced concepts such as packaging and monitoring.
Learn about Spring profiles, @Profile, profile-specific beans and properties, profile groups and activating a certain profile during startup.
Learn to use @PropertySource, @Value and @ConfigurationProperties annotations to register property files and inject configuration properties.
HikariCP is a lightweight JDBC connection pool. Learn about various options for configuring the HikariCP with Spring boot JPA and hibernate.
Testing a Spring Boot application means checking each layer on its own, the controller, the service and the repository, and then checking all layers together. Spring Boot supports these tests with slice annotations such as @WebMvcTest and @DataJpaTest, which test one layer, and with @SpringBootTest, which starts the application. The …
Use @RestClientTest and MockRestServiceServer to verify an outgoing Spring Boot 4 RestClient request, JSON mapping, and 404 handling with runnable tests.
Test Spring Data JPA repositories with @DataJpaTest on Spring Boot 4.1.2. Run H2 query tests, verify rollback behavior, and see how to keep a configured datasource.
Spring boot @Repository annotation is a specialization of the @Component to indicate a data repository used for storage, retrieval, and search behavior.
Spring boot makes application development easier but we may face some tough interview questions when it comes to test your knowledge on how it all works. Be prepare for the next job interview with given Spring boot interview questions and answers.
Configure a DataSource in Spring Boot 4 with spring.datasource.url, username and password, and Spring Boot creates a HikariCP pool. Tested examples for pool tuning, DataSourceBuilder, a second DataSource, schema.sql and data.sql, and tests with H2 and Testcontainers.
Build a Spring Boot 4 AOP aspect that measures order service methods. Run tests showing advice on successful and failed calls, and why self invocation bypasses the Spring proxy.
Send an order confirmation with a CSV attachment and inline image using Spring Boot 4.1.2. Test the received MIME parts with a local GreenMail SMTP server.
Learn to add internationalization (i18n) support to Spring Boot REST APIs through the auto-configuration of MessageSource and translation files.
Learn to enable HTTP response gzip compression in a Spring Boot application. By default, the gzip compression is disabled in Spring Boot.
Produce JSON from @RestController methods and consume it with @RequestBody in Spring Boot 4 with Jackson 3. Covers the 400, 415 and 406 errors, Jackson 3 defaults, spring.jackson properties, a JsonMapperBuilderCustomizer, annotations, Gson and tests.
Learn to write unit tests and integration tests in spring boot applications along with spring context, test annotations and mock support.
Use Spring Boot 4 @MockitoBean in MVC slice and full-context controller tests. Compare it with a plain Mockito mock and see when a missing bean is created or an existing one replaced.
Test a Spring WebFlux controller with @WebFluxTest, WebTestClient and @MockitoBean on Spring Boot 4.1.2. Verify JSON, 404 responses and the difference from a live-server test.
Test a Spring Boot 4.1.2 REST API with @SpringBootTest and H2. Compare real HTTP and MockMvc tests, seed data with @Sql, and mock only the notification boundary.
Test a Spring Boot REST controller with JUnit and Mockito. Compare direct method tests, standalone MockMvc and @WebMvcTest using verified GET, POST and 404 examples.
The @SpringBootTest annotation in Spring Boot allows us to create integration tests by loading the entire application context. It acts as a bridge between the application configuration and the test framework so that tests can verify the behavior of your application in an environment similar to production.
Use Spring Boot @TestConfiguration to add fixed test beans without losing production wiring. Compare nested and imported configurations in a runnable Boot 4.1.2 example.
Learn to include JUnit 5 in a Spring boot application and write unit tests. Check out a demo of JUnit 5 tests for Spring Boot REST controller.
Use Gson with Spring Boot 4.1.2. Compare an injected Gson bean with MVC JSON responses, customize LocalDate, and select Gson for the message converter.
Read a classpath file in Spring Boot with Resource, ClassPathResource, or ResourceLoader. See why streams work in a packaged JAR when getFile() does not.
At a high level, @RestController is a convenient annotation for writing REST APIs and combines @Controller and @ResponseBody annotations.
Turn off the Spring Boot startup banner with properties, a launch argument, or SpringApplication. See verified Spring Boot 4.1.2 output and how overrides work.
Understand Spring Boot 4 application and auto-configuration annotations with a runnable example of property conditions, missing beans, and three outcomes.
Give each Spring Boot profile its own log levels, files and format with application-{profile}.properties or springProfile blocks in logback-spring.xml, including JSON logs only in production.
Learn to use and configure logging to console in spring boot application. Also learn to configure and use console appenders available in logback and log4j2.
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