import java.util.jar.Attributes
import java.util.jar.JarFile

File artifact = new File( basedir, "target/jetty-runner.jar" )
assert artifact.exists()

JarFile jar = new JarFile( artifact );

Attributes manifest = jar.getManifest().getMainAttributes();

assert manifest.getValue( new Attributes.Name( "Main-Class" ) ).equals( "org.eclipse.jetty.ee8.runner.Runner" )
