Following shows that the version for the compiler plugin is missing
[INFO] Scanning for projects...
[WARNING]
[WARNING] Some problems were encountered while building the effective model for org.opensky:opensky-api:jar:1.1.0
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-comp iler-plugin is missing. @ line 12, column 21
[WARNING]
[WARNING] It is highly recommended to fix these problems because they threaten t he stability of your build.
[WARNING]
[WARNING] For this reason, future Maven versions might no longer support buildin g such malformed projects.
[WARNING]
Following shows that the version for the compiler plugin is missing
[INFO] Scanning for projects... [WARNING] [WARNING] Some problems were encountered while building the effective model for org.opensky:opensky-api:jar:1.1.0 [WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-comp iler-plugin is missing. @ line 12, column 21 [WARNING] [WARNING] It is highly recommended to fix these problems because they threaten t he stability of your build. [WARNING] [WARNING] For this reason, future Maven versions might no longer support buildin g such malformed projects. [WARNING]