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多选题
Given the following code fragment:     public void create() {     Vector myVect;     myVect = new Vector();      }  Which of the following statements are true?()
A

The declaration on line 2 does not allocate memory space for the variable myVect.

B

The declaration on line 2 allocates memory space for a reference to a Vector object.

C

The statement on line 2 creates an object of class Vector.

D

The statement on line 3 creates an object of class Vector.

E

The statement on line 3 allocates memory space for an object of class Vector.


参考答案

参考解析
解析: SL-275中指出:要为一个新对象分配空间必须执行new Xxx()调用,new调用执行以下的操作: 
1.为新对象分配空间并将其成员初始化为0或者null。 
2.执行类体中的初始化。(例如在类中有一个成员声明int a=10;在第一步后a=0 ,执行到第二步后a=10)    
3.执行构造函数。 
4.变量被分配为一个到内存堆中的新对象的引用。
更多 “多选题Given the following code fragment:     public void create() {     Vector myVect;     myVect = new Vector();      }  Which of the following statements are true?()AThe declaration on line 2 does not allocate memory space for the variable myVect.BThe declaration on line 2 allocates memory space for a reference to a Vector object.CThe statement on line 2 creates an object of class Vector.DThe statement on line 3 creates an object of class Vector.EThe statement on line 3 allocates memory space for an object of class Vector.” 相关考题
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考题 单选题You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create a Web form in the application by using the following code fragment:   01     02 protected void Button_Handler(object sender, EventArgs e)   03 {   04   // some long-processing operation.  05 }   06    07  A AB BC CD D

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考题 单选题Given the following code:     public class Person{     int arr[] = new int[10];  public static void main(String a[]) {     System.out.println(arr[1]);     }     }  Which statement is correct?()A  When compilation some error will occur.B  It is correct when compilation but will cause error when running.C  The output is zero.D  The output is null.

考题 单选题Given the following code:    public class Test {  void printValue(int m){  do {  System.out.println("The value is"+m);     }  while( --m  10 )     }  public static void main(String arg[]) {     int i=10;  Test t= new Test();     t.printValue(i);     }     }  Which will be output?()A  The value is 8B  The value is 9C  The value is 10D  The value is 11

考题 单选题You work as an application developer at Certkiller .com. You have been given the task of developing a Windows service application that regularly monitors other Windows services on the same computer. This Windows service application must also log any abnormal file system activity. You have added the following class to the Windows service application: public class EnumerateService : ServiceBase { public static EnumerateService () { this.ServiceName = "Enumerate Service"; this.CanStop = true; } protected override void OnStart (string[] args) { // Enumerate all services and initialize the FileSystemWatcher } protected override void OnStop () { // Stop the FileSystemWatcher and perform cleanup } public static void Main () { EnumerateService service = new EnumerateService(); } } You then create the installer for the Windows service application, and install the Windows service application. You have configured the Windows service Startup type to Automatic, and rebooted the system. You then test the new Windows service application, and find that it is not working.You need to ensure that the service is working properly. What should you do?()A  Override the OnBoot method instead of the OnStart method.B  Replace the Main method code with the following code: EnumerateService service = new EnumerateService (); Service.Run ();C  Override the OnLoad method instead of the OnStart method.D  Replace the Main method code with the following code: EnumerateService service = new EnumerateService (); Run (service);