# Spring Boot 3 New Features

The Spring team released Spring Boot 3 in November 2022.

Here are the most important new features of Spring Boot 3.0 :

1. We need minimum JDK 17

In this case we can use the new improvements of JDK 17 or greater

2. Jakarta EE 9 is used instead Java EE

The package namespace changed from javax.* to jakarta.*.

3. Spring Observability improvements

Spring Boot 3 is using Micrometer and Micrometer Tracing (formerly Spring Cloud Sleuth). Now, developers can record various application metrics and provide tracing support to tools such as OpenZipkin and OpenTelemetry.

4. GraalVM Native Image Support

With Spring Boot 3.0, developers can convert applications directly into GraalVM native image. This is a built-in support for creating native executables through Ahead-of-Time (AOT) compilation with GraalVM Native Image compiler. Using this feature, the Java applications have a lesser memory footprint and a faster execution.

5. Log4j2 Enhancements

The <SpringProfile> tag lets developers create custom configurations based on active Spring profiles. Log4j2 can be customized based on Spring Boot properties.

6. Simplified configuration of Testcontainers

Starting from Spring Boot 3.1, the new @ServiceConnection annotation can be used on the container instance fields of your tests. In this case the connection to the database, message broker, etc started on that container will be done under the hood, without using @DynamicPropertySource. More information you have here.