砂卵石及含水地层不宜使用的不开槽管道施工方法是()。 ["定向钻","浅埋暗挖","密闭式顶管","盾构"]
《水法》从保持河道、运河、渠道畅通以及保证湖泊、水库正常发挥效益出发,针对各类生产建设活动的特点以及可能产生的危害,分别作出了()。 ["禁止性规定","非禁止性规定和限制性规定","禁止性规定和非限制性规定","禁止性规定和限制性规定"]
外汇结构性存款按照本金有无风险划分,可分为()。 ["本金无风险类存款","利息有风险类存款","利息无风险类存款","本金有风险类存款"]
曲状元
public class MyLogger { private StringBuilder logger = new StringBuuilder(); public void log(String message, String user) { logger.append(message); logger.append(user); } } The programmer must guarantee that a single MyLogger object works properly for a multi-threaded system. How must this code be changed to be thread-safe?() [" synchronize the log method"," replace StringBuilder with StringBuffer"," No change is necessary, the current MyLogger code is already thread-safe."," replace StringBuilder with just a String object and use the string concatenation (+=) within the log method"]
“水族馆”的音乐再现内容是什么?