code: @Test public void testAcceptProvidedExtensionAsClient() throws Exception {
    DefaultExtension defaultExtension=new DefaultExtension();
    assertTrue(defaultExtension.acceptProvidedExtensionAsClient("Test"));
    assertTrue(defaultExtension.acceptProvidedExtensionAsClient(""));
    assertTrue(defaultExtension.acceptProvidedExtensionAsClient("Test, ASDC, as, ad"));
    assertTrue(defaultExtension.acceptProvidedExtensionAsClient("ASDC, as,ad"));
    assertTrue(defaultExtension.acceptProvidedExtensionAsClient("permessage-deflate"));
  }
  