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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。
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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