private static Artifact newArtifact(String group, String artifactId, String version) {
    Artifact artifact = new DefaultArtifact(group, artifactId, version, null, "jar", "", null);
    artifact.setFile(new File("/tmp/" + group + artifactId + version));
    return artifact;
  }
Helper for reading back layers in a {@link BuildContext}.
jib-maven-plugin/src/test/java/com/google/cloud/tools/jib/maven/MavenProjectPropertiesTest.java