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。
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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