### Question:
MavenRepository implements ClassLoaderFactory { public ClassLoader getClassLoader( ClassLoader parent, MavenId... mavenIds ) { CheckArg.isNotEmpty(mavenIds, "mavenIds"); CheckArg.containsNoNulls(mavenIds, "mavenIds"); return this.classLoaders.getClassLoader(parent, mavenIds); } MavenRepository( final MavenUrlProvider urlProvider ); ClassLoader getClassLoader( ClassLoader parent,
                                       MavenId... mavenIds ); ClassLoader getClassLoader( String... coordinates ); ClassLoader getClassLoader( ClassLoader parent,
                                       String... coordinates ); boolean exists( MavenId mavenId ); Set<MavenId> exists( MavenId firstId,
                                MavenId... mavenIds ); List<MavenDependency> getDependencies( MavenId mavenId ); URL getUrl( MavenId mavenId,
                       ArtifactType artifactType,
                       SignatureType signatureType ); URL getUrl( MavenId mavenId,
                       ArtifactType artifactType,
                       SignatureType signatureType,
                       boolean createIfRequired );  }### Answer:
@Test( expected = IllegalArgumentException.class ) public void shouldNotAllowZeroIdsWhenGettingClassLoader() { maven.getClassLoader(parentLoader, (MavenId[])null); }
@Test( expected = IllegalArgumentException.class ) public void shouldNotAllowNullIdsWhenGettingClassLoader() { maven.getClassLoader(parentLoader, mavenId1, null, mavenId2); }