p.setWeight(420);
p.changePayload(420);
p = new Payload(420);
Payload.setWeight(420);
p = Payload.setWeight(420);
p = new Payload(); p.setWeight(420);
第1题:
10. interface Foo { int bar(); } 11. public class Sprite { 12. public int fubar( Foo foo) { return foo.bar(); } 13. public void testFoo() { 14. fubar( 15. // insert code here 16.); 17. } 18. } Which code, inserted at line 15, allows the class Sprite to compile?()
第2题:
1. package foo; 2. 3. import java.util.Vector; 4. 5. private class MyVector extends Vector { 6. int i = 1; 7. public MyVector() { 8. i = 2; 9. } 10. } 11. 12. public class MyNewVector extends MyVector { 13. public MyNewVector () { 14. i = 4; 15. } 16. public static void main (String args []) { 17. MyVector v = new MyNewVector(); 18. } 19. } The file MyNewVector.java is shown in the exhibit. What is the result?()
第3题:
请使用VC6或使用【答题】菜单打开考生文件夹proj2下的工程proj2,其中定义了vehiele类,并派生出motorcar类和bicycle类。然后以motorcar和bicycle作为基类,再派生出motorcycle类。要求将Vehicle作为虚基类,避免二义性问题。请在程序中的横线处填写适当的代码并删除横线,以实现上述类定义。此程序的正确输出结果应为:
80
150
100
1
注意:只能在横线处填写适当的代码,不要改动程序中的其他内容,也不要删除或移动“//****found****”。
include<iostream.h>
class vehicle
{
private:
int MaxSpeed;
int Weight;
public:
//*************found************
vehicle(int maxspeed,int weight):——
~vehicle{};
int getMaxSpeed{return MaxSpeed;}
int getWeight{retum Weight;}
};
//****************found************
class bicycle:——public vehicle
{
private:
int Height;
public:
bicycle(int maxspeed,int weight,int height):vehicle(maxspeed,weight),Height(height){}
int getHeight{retum Height;};
};
//*******************found**************
class motorcar:——public vehicle
{
private:
int SeatNum;
public:
motorcar(int maxspeed。int weight,int seatnum):vehicle(maxspeed,weight),SeatNum(seatnum){}
int getSeatNum{return SeatNum;};
};
//*****************found***************
class motorcycle:——
{
public:
motorcycle(int maxspeed,int weight,int height):vehicle(maxspeed,weight),bicycle(maxspeed,weight,
height),motorcar(maxspeed,weight,1){}
};
void main
{
motorcycle a(80,150,100);
cout<<a.getMaxSpeed<<endl;
cout<<a.getWeight<<endl;
cout<<a.getHeight<<endl;
cout<<a.getSeatNum<<endl;
}
(1)MaxSpeed(maxspeed),Weight(weight){f;
(2)virtual
(3)virtua1
(4)public bicycle,public motorcar
第4题:
11. public class Test { 12. public void foo() { 13. assert false; 14. assert false; 15. } 16. public void bar(){ 17. while(true){ 18. assert false; 19. } 20. assert false; 21. } 22. } What causes compilation to fail?()
第5题:
11. class Animal { public String noise() { return “peep”; } } 12. class Dog extends Animal { 13. public String noise() { return “bark”; } 14. } 15. class Cat extends Animal { 16. public String noise() { return “meow”; } 17. } ..... 30. Animal animal = new Dog(); 31. Cat cat = (Cat)animal; 32. System.out.printIn(cat.noise()); What is the result?()
第6题:
10. abstract public class Employee { 11. protected abstract double getSalesAmount(); 12. public double getCommision() { 13. return getSalesAmount() * 0.15; 14. } 15. } 16. class Sales extends Employee { 17. // insert method here 18. } Which two methods, inserted independently at line 17, correctly complete the Sales class?()
第7题:
1. public class Test { 2. public static String output =””; 3. 4. public static void foo(int i) { 5. try { 6. if(i==1) { 7. throw new Exception(); 8. } 9. output += “1”; 10. } 11. catch(Exception e) { 12. output += “2”; 13. return; 14. } 15. finally { 16. output += “3”;17. } 18. output += “4”; 19. } 20. 21. public static void main(String args[]) { 22. foo(0); 23. foo(1); 24. 25. }26. } What is the value of the variable output at line 23?()
第8题:
请问下述代码中: int operator+(…)起什么作用?this 是什么?ccc 的值最终为多少?
class Fruit
{
public:
Fruit()
{
weight = 2;
}
Fruit(int w)
{
weight = w;
}
int operator+(Fruit f)
{
return this->weight * f.weight;
}
private:
int weight;
};
Fruit aaa;
Fruit bbb(4);
int ccc = aaa + bbb;
第9题:
public class Score implements Comparable
第10题:
11. class Payload { 12. private int weight; 13. public Payload(int wt) { weight = wt; } 13. public void setWeight(mt w) { weight = w; } 15. public String toString { return Integer.toString(weight); } 16. } 17. 18. public class TestPayload { 19. static void changePayload(Payload p) { 20. /* insert code here */ 21. } 22. 23. public static void main(String[] args) { 24. Payload p = new Payload(); 25. p.setWeight(1024); 26. changePayload(p); 27. System.out.println(”The value of p is “+ p); 28. } 29. } Which statement, placed at line 20, causes the code to print “The value of p is 420.”?()