问题:以下对Scoket类的描述中,错误的是() A、Scoket类处于应用层B、利用Scoket类进行网络通讯时,不需要考虑具体的接入方式C、利用Scoket类进行网络通讯时,只能采取客户端发送消息,服务器反馈消息的机制D、利用Scoket类进行网络通讯时,首先需要确定服务器和客户端
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问题: 现有: class Dog{ } class Harrier extends Dog { } class DogTest{ public static void main (String [] args) { Dog dl=new Dog(); Harrier hl=new Harrier(); Dog d2=hl; Harrier h2= (Harrier) d2; Harrier h3=d2; } } 下面哪一项是正确的?() A、2个Dog对象被创建B、2个Harrier对象被创建C、3个Harrier对象被创建D、编译失败
问题: 现有: 1. class Book { 2. private final void read() { System.out.print("book "); } 3. } 4. class Page extends Book { 5. public static void main(String [] args) { 6. // insert code here 7. } 8. private final void read() { System.out.print("page "); } 9. } 和如下三个代码片段 ( x, y, z ): x. // just a comment y. new Page().read(); z. new Book().read(); 分别插入到第6行,有几个允许代码通过编译并可以运行且无异常?() A、 0B、 1C、 2D、 3
问题:Which two JSTL URL-related tags perform URL rewriting?()A、UrlB、LinkC、ParamD、ImportE、Redirect
问题:HTTP中的POST和GET在下列哪些方面有区别()。A、数据位置B、明文密文C、数据安全D、长度限度E、应用场景
问题:以下有关接口的叙述错误的是哪项?() A、 一个类可以实现多个接口B、 接口不能被继承C、 类实现接口时必须实现其中的方法D、 接口中只能包含抽象方法和常量
问题:能够遍历泛型List〈Integer〉 al中的所有元素的语句是哪项?() A、for(Integer i : al)B、for(i : al)C、for(al)D、forEach(Integer i : al)
问题:Which statements concerning the event model of the AWT are true?() A、At most one listener of each type can be registered with a component.B、Mouse motion listeners can be registered on a List instance.C、There exists a class named ContainerEvent in package java.awt.event.D、There exists a class named MouseMotionEvent in package java.awt.event.E、There exists a class named ActionAdapter in package java.awt.event.
问题: public class TestString 1 { public static void main(String[] args) { String str = “420”; str += 42; System.out.print(str); } } What is the output?()A、 42B、 420C、 462D、 42042E、 Compilation fails.F、 An exception is thrown at runtime.
问题:Which code determines the int value foo closest to, but not greater than, a double value bar?() A、 Int foo = (int) Math.max(bar);B、 Int foo = (int) Math.min(bar);C、 Int foo = (int) Math.abs(bar);D、 Int foo = (int) Math.ceil(bar);E、 Int foo = (int) Math.floor(bar);F、 Int foo = (int) Math.round(bar);
问题: The Squeaky Bean company has decided to port their web application to a new J2EE 1.4 container. Whilereviewing the application, a developer realizes that in multiple places within the current application, nearlyduplicate code exists that finds enterprise beans. Which pattern should be used to eliminate this duplicatecode?()A、Transfer ObjectB、Front ControllerC、Service LocatorD、Intercepting FilterE、Business DelegateF、Model-View-Controller
问题: Given the HttpServlet code: getServletContext().setAttribute(“foo”, “value”); What is the result?()A、 The attribute foo is placed in the applicationB、 A ServletContextListener registered for that servlet is notifiedC、 A ServletAttributeListener registered for that servlet is notifiedD、 An HttpSessionAttributeListener registered for that servlet is notified
问题: 10. public class Foo implements java.io.Serializable { 11. private int x; 12. public int getX() { return x; } 12.publicFoo(int x){this.x=x; } 13. private void writeObject( ObjectOutputStream s) 14. throws IOException { 15. // insert code here 16. } 17. } Which code fragment, inserted at line 15, will allow Foo objects to be correctly serialized and deserialized?() A、 s.writeInt(x);B、 s.serialize(x);C、 s.writeObject(x);D、 s.defaultWriteObject();
问题: 现自: class Car implements Serializable () class Ford extends Car {} 如果试图序列化一个Ford实例,结果为() A、编译失败B、两个对象被序列化C、—个对象被序列化D、运行时异常被抛出
问题:Java中方法绑定有哪些形式?()A、编译时刻绑定B、运行时刻绑定C、静态绑定D、私有绑定
问题: 现有: public class Tester { public static void main (String[] args) { intx-5; Integer xl=x; Integer x2=x; int x3=new Integer(5); system..ut.print(x1.equals(x)); system..ut.print(xl==x); system..ut.print(x2.equals(xl)); system..ut.print(x2==xl); system..ut.print(x2==x3); system..ut.print(x2.equals(x3)); } } 结果为:() A、编译失败B、falsefalsetruetruetruetrueC、truetruetruetruetruetrueD、falsefalsetruetruetruefalseE、truefalsetruefalsefalsetrueF、运行时异常被抛出
问题: A developer is designing a multi-tier web application and discovers a need to hide the details of establishingand maintaining remote communications from the client. In addition, the application needs to find,in a transparent manner,the heterogeneous business components used to service the client’s requests. Which design patterns, working together, address these issues?()A、Business Delegate and Transfer ObjectB、Business Delegate and Service LocatorC、Front Controller and Business DelegateD、Intercepting Filter and Transfer Object
问题:下列哪项是String的字面量?() A、“Hello”B、‘world’C、/u2345D、new String(“good”)
问题: public class Parent{ public void change(int x){} } public class Child extends Parent{ //覆盖父类change方法 } 下列哪个声明是正确的覆盖了父类的change方法?() A、 protected void change(int x){}B、 public void change(int x, int y){}C、 public void change(String s){}D、 public void change(int x){}
问题:Which of the following statements about variables and their scopes are true? () A、 Instance variables are member variables of a class.B、 Instance variables are declared with the static keyword.C、 Local variables defined inside a method are created when the method is executed.D、 Local variables must be initialized before they are used.