### Question:
ClassUtil { public static List< String > classpathEntriesUnder( final String rootPackage ) { final List< String > results = new ArrayList<>(); Enumeration< URL > en = null; if( StringUtils.isNotEmpty( rootPackage ) ) { try { en = ClassUtil.class.getClassLoader().getResources( rootPackage ); } catch( final IOException e ) { log.error( e.getMessage(), e ); } } while( en != null && en.hasMoreElements() ) { final URL url = en.nextElement(); try { if( "jar".equals( url.getProtocol() ) ) { jarEntriesUnder( results, ( JarURLConnection )url.openConnection(), rootPackage ); } else if( "file".equals( url.getProtocol() ) ) { fileEntriesUnder( results, new File( url.getFile() ), rootPackage ); } } catch( final IOException ioe ) { log.error( ioe.getMessage(), ioe ); } } return results; } private  ClassUtil(); static Class<?> findClass( final List< String > packages,  final List< String > externaljars, final String className ); static Class< ? > findClass( final String packageName, final String className ); static List< String > classpathEntriesUnder( final String rootPackage ); @SuppressWarnings("unchecked") static T getMappedObject( final String requestedClass ); @SuppressWarnings( "unchecked" ) static T getMappedObject( final String requestedClass, final Object... initargs ); static Class< ? > getMappedClass( final String requestedClass ); static boolean assignable( final String srcClassName, final String parentClassName ); static boolean exists( final String className ); static Map< String, String > getExtraClassMappings(); static final String MAPPINGS; static final String MAPPINGS_EXTRA; }### Answer:
@Test public void testClasspathSearch() { final List< String > jarSearch = ClassUtil.classpathEntriesUnder( "META-INF" ); Assertions.assertNotNull( jarSearch ); Assertions.assertTrue( jarSearch.size() > 0 ); final List< String > fileSearch = ClassUtil.classpathEntriesUnder( "templates" ); Assertions.assertNotNull( fileSearch ); Assertions.assertTrue( fileSearch.size() > 0 ); final List< String > nullSearch = ClassUtil.classpathEntriesUnder( "blurb" ); Assertions.assertNotNull( nullSearch ); Assertions.assertEquals( 0, nullSearch.size() ); final List< String > nullInputSearch = ClassUtil.classpathEntriesUnder( null ); Assertions.assertNotNull( nullInputSearch ); Assertions.assertEquals( 0, nullSearch.size() ); }