public void test_getAdaptiveExtension_customizeKey() throws Exception {
Ext1 ext = ExtensionLoader.getExtensionLoader(Ext1.class).getAdaptiveExtension();
Config config = Config.fromKv("protocol", "p1", "host", "1.2.3.4", "port", "1010", "path", "path1", "key2", "impl2");
String echo = ext.yell(config, "haha");
assertEquals("Ext1Impl2-yell", echo);
config = config.addConfig("key1", "impl3");
echo = ext.yell(config, "haha");
assertEquals("Ext1Impl3-yell", echo);