// test
assertNotNull(extension);
assertEquals(WebSocketServerExtension.RSV1, extension.rsv());
assertTrue(extension.newExtensionDecoder() instanceof PerMessageDeflateDecoder);
assertTrue(extension.newExtensionEncoder() instanceof PerMessageDeflateEncoder);
// execute
data = extension.newReponseData();
assertEquals(PERMESSAGE_DEFLATE_EXTENSION, data.name());