Apollo:客户端订阅代码？

import com.ctrip.framework.apollo.Config;
import com.ctrip.framework.apollo.ConfigService;
import com.ctrip.framework.apollo.model.ConfigChangeEvent;
import com.ctrip.framework.apollo.model.ConfigChangeListener;

public class ApolloClient {

    public static void main(String[] args) {
        // 获取默认命名空间的配置对象
        Config config = ConfigService.getAppConfig();

        // 添加配置变更监听器
        config.addChangeListener(new ConfigChangeListener() {
            @Override
            public void onChange(ConfigChangeEvent changeEvent) {
                // 配置发生变化时的处理逻辑
                System.out.println("Config changed: " + changeEvent.changedKeys());
            }
        });
    }
}