Unknown referenced nature: org.springframework.ide.eclipse.core.springnature

Question

In STS 4, my Java 10 Spring Boot 2.1 project warns me:

Unknown referenced nature: org.springframework.ide.eclipse.core.springnature

How can I fix this?

Answer 1

This is a left-over from a prior STS brought-in by the .project file due to a known issue.

To fix this, delete the project from your workspace(s) in STS, and remove the project meta-data from the file system:

  rm .project
  rm .classpath
  rm .factorypath
  rm -rf .settings

When you re-import the project, STS 4 will build proper project meta-data.

Answer 2

Open the .project file in your source folder and comment/delete this line:

<nature>org.springframework.ide.eclipse.core.springnature</nature>