I looked at the release notes for Spring Boot 2.0.0.M1 not expecting a lot of exciting changes but was surprised by some compelling things. There is the usual “deprecated classes are removed” and “Dependency X is upgraded” but there are some more exciting changes.

Java 8 Only

I think we can all agree that this is a good thing and a long time coming.

HikariCP over Tomcat Connection Pooling

I was happy to see Spring Boot 2 changing the connection pooling library to HikariCP. I’ve used HikariCP in past projects and its great for high-performance services. As it’s documentation states “There are a lot of knobs to tweak” so I assume that they will be exposed in application.properties. Luckily HikariCP works well out-of-the-box with no tweaks.

Better Gradle Support

I always felt that Gradle has been a second-class citizen in the Spring Boot world but they are making strides to change that in Spring Boot 2. You can see a list of their closed issues. Things I really liked seeing:

• bootJar and bootWar now extend the jar and war tasks. This fits better into Gradle’s model and makes it a better Gradle citizen. See the Github issue for some interesting reading.
• The minimal Gradle version is 3.4 and it supports Reproducible Builds and so does Spring Boot 2.
• Some Spring Boot tasks weren’t listed in the correct section running gradle tasks. This sounds like a simple thing, but I think it’s a good change, especially for people just coming to Spring Boot.

Spring Boot 2 is only on Milestone 2 with a full release scheduled in November, so we still have a long ways to go but I like the changes I see so far!