多项选择题
public class Car {
private int wheelCount;
private String vin;
public Car(String vin) {
this.vin = vin;
this.wheelCount = 4;
}
public String drive() {
return “zoom-zoom”;
}
public String getInfo() {
return “VIN: “+ vin + “wheels: “+ wheelCount;
}
}
And:
public class MeGo extends Car {
public MeGo(String vin) {
this.wheelCount = 3;
}
}
What two must the programmer do to correct the compilation errors?()
A. insert a call to this() in the Car constructor
B. insert a call to this() in the MeGo constructor
C. insert a call to super() in the MeGo constructor
D. insert a call to super(vin) in the MeGo constructor
E. change the wheelCount variable in Car to protected
F. change line 3 in the MeGo class to super.wheelCount = 3;
相关考题
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单项选择题
10. public class Hello { 11. String title; 12. int value; 13. public Hello() { 14. title += “ World”; 15. } 16. public Hello(int value) { 17. this.value = value; 18. title = “Hello”; 19. Hello(); 20. } 21. } and: 30. Hello c = new Hello(5); 31. System.out.println(c.title); What is the result?()
A. Hello
B. Hello World
C. Compilation fails.
D. Hello World 5
E. The code runs with no output.
F. An exception is thrown at runtime. -
单项选择题
1. public class SimpleCalc { 2. public int value; 3. public void calculate() { value += 7; } 4. } And: 1. public class MultiCalc extends SimpleCalc { 2. public void calculate() { value -= 3; } 3. public void calculate(int multiplier) { 4. calculate(); 5. super.calculate(); 6. value *=multiplier; 7. } 8. public static void main(String[] args) { 9. MultiCalc calculator = new MultiCalc(); 10. calculator.calculate(2); 11. System.out.println(”Value is: “+ calculator.value); 12. } 13. } What is the result?()
A. Value is: 8
B. Compilation fails.
C. Value is: 12
D. Value is: -12
E. The code runs with no output.
F. An exception is thrown at runtime. -
多项选择题
1. class Super { 2. private int a; 3. protected Super(int a) { this.a = a; } 4. } ..... 11. class Sub extends Super { 12. public Sub(int a) { super(a); } 13. public Sub() { this.a= 5; } 14. } Which two, independently, will allow Sub to compile?()
A. Change line 2 to: public int a;
B. Change line 2 to: protected int a;
C. Change line 13 to: public Sub() { this(5); }
D. Change line 13 to: public Sub() { super(5); }
E. Change line 13 to: public Sub() { super(a); }
