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.

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。

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