用Singleton如何写设计模式

在Spring配置文件里，为了创建多实例的对象，应对标签＜bean＞设置属性scope=“singleton"。( )

以下有关Bean的singleton作

Singleton （单件）模式属于结构性模式。

在（）适合使用单例（Singleton）模式。

Word中插入数学公式的方法是（）。 A: "插入"→"形状"→"公式" B: "开发工具"→"公式" C: "插入"→"公式"→"插入新公式" D: "引用"→"插入"→"公式"

singleton是spring容器默认的作用域

定义并初始化一个用于存放我们国家的四个直辖市的数组cityName，四个直辖市为：北京，上海，天津，重庆. 正确的是_________ A: String[] cityName=new String[4]{"北京","上海","天津","重庆"}; B: String[] cityName=new String[]{"北京","上海","天津","重庆"}; C: String[] cityName={"北京","上海","天津","重庆"}; D: String cityName = new String[4] { "北京", "上海", "天津", "重庆" };

已知有一个名为names的空列表,如何向其中添加old_driver,rain,jack,shanshan,peiqi,black_girl 元素？ A: names.append("old_driver","rain","jack","shanshan","peiqi","black_girl") B: names.extend("old_driver","rain","jack","shanshan","peiqi","black_girl") C: names.insert("old_driver","rain","jack","shanshan","peiqi","black_girl") D: names.extend(["old_driver","rain","jack","shanshan","peiqi","black_girl"])

以下哪个选项是正确的json数据格式： A: { "id": 2, "userName": admin, "passWord": 12345, "email": admin@qq.com} B: { id: 2, userName: "admin", passWord: "12345", email: "admin@qq.com"} C: { "id": 2, "userName": "admin", "passWord": "12345", "email": "admin@qq.com",} D: { "id": 2, "userName": "admin", "passWord": "12345", "email": "admin@qq.com"}