Is Spring Boot 4 supported now?

[ahhdgahghs]

Currently using SpringBoot 4 and JAVA16, now using the JJWT package, but not sure if it's compatible.

[darekwojciechowski]

JJWT has no Spring dependency at all — it's plain Java with no framework coupling, so there's nothing for Spring Boot 4 to be incompatible with. Boot 4 doesn't change anything JJWT touches. Use it as normal.

The thing that will actually bite you is the Java version. You mention Java 16, but Spring Boot 4 has a JDK 17 baseline. If you're really on 16, Boot 4 won't start regardless of JJWT. Run java -version and move to 17 or newer if it says 16.

While you're there, check your dependency scopes — this is the most common JJWT setup mistake. You need three artifacts, all on the same version (0.13.0 at the moment):

• jjwt-api — compile scope
• jjwt-impl — runtime scope
• jjwt-jackson — runtime scope

Only jjwt-api should be compile scope. If impl and jackson are compile scope too it still builds, but you can end up importing internal classes that change between releases without notice.

In Gradle that's:

implementation 'io.jsonwebtoken:jjwt-api:0.13.0'
runtimeOnly 'io.jsonwebtoken:jjwt-impl:0.13.0'
runtimeOnly 'io.jsonwebtoken:jjwt-jackson:0.13.0'

In Maven, same three artifacts with <scope>runtime</scope> on the last two.

[ahhdgahghs]

Perfect, that answers all my questions. Thanks a lot!

[darekwojciechowski]

Anytime, glad it helped! 🙌 Ping me if anything else comes up.