### Question:
WWWConnection extends AbstractBlobStoreConnection { @Override public Iterator<URI> listBlobIds(String filterPrefix) throws IOException { throw new UnsupportedOperationException("blob-id listing not supported"); } WWWConnection(WWWStore store, Map<String, URLStreamHandler> handlers,
                       StreamManager streamManager); @Override void close(); @Override Blob getBlob(URI blobId, Map<String, String> hints); @Override Iterator<URI> listBlobIds(String filterPrefix); @Override void sync();  }### Answer:
@Test(expectedExceptions = { UnsupportedOperationException.class }) public void testListBlobIds() throws IOException { con.listBlobIds(null); }