Spring boot latest version 2.4.0 is available now !!

Overview

In this article, we begin exploring what change in Spring Boot latest version

What's new in Spring Boot 2.4

Spring Boot 2.4.0 has been released and is now available from repo.spring.io and Maven Central.

This update contains 2.4.0 is the first generally available Spring Boot release that uses the new versioning scheme. Please note that the version is 2.4.0 rather than 2.4.0.RELEASE that you may have expected based on previous releases. This release adds a significant number of new features and improvements

Spring Boot 2.4.0 uses Spring Framework 5.3 and has support for Java 15 while also remaining compatible with Java 11 and 8. listed below features/enhancements as part of the Spring Boot 2.4.0.

1. Docker/Buildpack Support
2. Layered jar enabled by default
3. Config File Processing (application properties and YAML files)
4. Volume Mounted Config Directory Trees
5. Startup Endpoint
6. Origin Chains

Docker/Buildpack Support:

Publishing Images The Maven spring-boot goal:build-image plugin and bootBuildImage task of the Gradle plugin can now publish the image created in a Docker registry. For more information on configuring plugins for publishing images, see the Maven and Gradle plugin documentation.

Authenticating You can now use a private authenticated Docker registry to build your builder or run an image by using Spring Boot's buildpack support. The token-based authentication is enabled. Username/Password.

Config File Processing (application properties and YAML files):

This release allows layered jars and provides layertools by default. This should improve the efficiency of the created image using the out-of-the-box build pack and allow you to take advantage of that feature when building a custom Dockerfile.

Volume Mounted Config Directory Trees:

The new spring.config.import property can be used to import configuration trees that are widely used with Kubernets. The configuration tree is an alternative way to have key/value pairs. Each pair is declared in its own file, with the file name forming the property key, and the contents of the file giving the value.

Properties loaded from the config tree have newline characters that have been trimmed by default.

Startup Endpoint:

A new endpoint for the startup actuator is now available that shows information about the startup of your applications. The endpoint will help you recognize beans that take longer than expected to start.

This work builds on the device startup monitoring feature recently added to Spring Framwork 5.3. You can read more about this feature in the Spring Framework Reference Guide.

Origin Chains:

The Origin interface has been modified to a new getParent() method. This allows us to provide a full origin chain that can show exactly where an item originated from.

For example, you may want to use spring.config.import in your application.properties to import a second file. The Origin of Properties loaded from this second file will have a parent that will point back to the original import declaration.

You can try this yourself by looking at the endpoints of the actuator/env or the actuator/configprops actuator endpoints.

Dependency upgrades

Spring Boot 2.4 moves to new versions of several Spring projects:
• Spring AMQP 2.3
• Spring Batch 4.3
• Spring Data 2020.0
• Spring Framework 5.3
• Spring HATEOAS 1.2
• Spring Integration 5.4
• Spring Kafka 2.6
• Spring Retry 1.3
• Spring Security 5.4
• Spring Session 2020.0