1
2
Compilation fails.
The code runs with no output.
An exception is thrown at runtime.
第1题:
下列程序的运行结果是【 】。
include <iostream. h>
class SomeClass
{
public:
SomeClass(int value) { some_value=value;};
void show_data(void) { cout<<data<<"<<~some_value<<endl; };
static void set_data(int value) {data=value; }
private:
static int data;
int some_value
};
int SomeClass::data
void main(void)
{
SomeClass my_class(1001),your_class(2002);
your_class. set_data(4004);
my_elass. show_data()
}
第2题:
有如下程序: #include<iostream> using namespace std; classA { public: A(){cout<<"A";} }; class B{public:B(){cout<<"B";}}; class C:public A { B b; public: C(){cout<<"C";} }; int main(){C obj;return 0;} 执行后的输出结果是( )
A.ABC
B.BAC
C.ACB
D.CBA
第3题:
有以下程序: #include<iostream> using namespace std; class A { private: int x; public: A(int a) { x=a; } friend class B; }; class B { public: void print(A a) { a.x--; cout<<a, x<<end1; } }; int main () { A a(10); B b; b.print (a) ; return 0; } 程序执行后的输出结果是( )。
A.9
B.10
C.11
D.12
第4题:
下列程序的运行结果是【 】。
include<iostream, h>
class Sample
{
int a;
public:
Sample(int aa=0) {a=aa;}
~Sample() {cout<<"Sample="<<a<<;}
class Derived: public Sample
{
int b;
public:
Derived(int aa=0, int bb=0): Sample(aa) {b=bb;}
~De rived() {cout <<"Derived="<<b<<'';}
void main()
{
Derived dl (9)
}
第5题:
有如下类声明: class Base{ protected: int amount; public: Base(int n=0):amount(n){} int getAmountconst{retum amount;} }; class Derived:public Base{ protected: int value; public: Derived(int m,int n):value(m),Base(n){} int getDataconst{return value+amount;} }: 已知x是一个Derived对象,则下列表达式中正确的是( )。
A.x.value+X.getAmount
B.x.getData一x.getAmount
C.x.getData一x.amount
D.x.value+X.amount
第6题:
下面程序段的输出结果为 package test; public class A { int x=20; static int y=6; public static void main(String args[]) { Class B b=new Class B(); b.go(10); System.out.println(”x=”+b.x); } } class Class B { int x; void go(int y) { ClassA a=new ClassA(); x=a.y; } }
A.x=10
B.x=20
C.x=6
D.编译不通过
第7题:
在下列源代码文件Test.java中,哪个选项是正确的类定义? ( )
A.public class test { public int x=0; public test(int x) { this.x=x; } }
B.public class Test { public int x=0; public Test(int x) { this.x=x; } }
C.public class Test extends Ti,T2 { public int x=0; public Test(int x) { this.x=x; } }
D.protected class Test extends T2 { public int x=0; public Test(int x) { this.x=x; } }
第8题:
public class ClassA{ public int getValue(){ int value=0; boolean setting=true; String title="Hello"; if(value||(setting && title=="Hello")){return 1;} if(value==1&title.equals("Hello")){return 2;} } } And: ClassA a=new ClassA(); a.getValue(); What is the result?()
第9题:
interface A { public int getValue() } class B implements A { public int getValue() { return 1; } } class C extends B { // insert code here } Which three code fragments, inserted individually at line 15, make use of polymorphism?()
第10题:
public abstract class Shape { private int x; private int y; public abstract void draw(); public void setAnchor(int x, int y) { this.x = x; this.y = y; } } Which two classes use the Shape class correctly?()
第11题:
420 is the output.
An exception is thrown at runtime.
All constructors must be declared public.
Constructors CANNOT use the private modifier.
Constructors CANNOT use the protected modifier.
第12题:
1
2
Compilation fails.
The code runs with no output.
An exception is thrown at runtime.
第13题:
若有以下程序: #include<iostream> usingnamespacestd; classA { private: int x; public: int x; void setx(int i) { x=i; } int getx() { return x; } }; class B:public A { private: int m; public: int p; void setvalue (int a,int b,int C) { setx(A) ; z=b; m=c; } void display() { cout<<getx()<<","<<z<<","<<m<<end1; } }; int main() { B obj; obj.setvalue(2,3,4); obj.display(); return 0; } 程序运行以后的输出结果是
A.产生语法错误
B.2,3,4
C.2,2,2
D.4,3,2
第14题:
请按下面注释的提示,将类B的构造函数定义补充完整。
classA
{
int a;
public:
A(int aa=0) {a=aa;)
};
Class B:public A
{
int b;
A c;
public:
//用aa初始化基数A,用aa+1初始化类对象成员c
B(int aa): (b=aa+2)
};
第15题:
在下列源代码文件Test.java中,正确定义类的代码是( )。
A.pblic class test { public int x=0; public test(int x) { this. x=x;} }
B.public class Test { public int x=0; public Test(int x) { this. x=x;} }
C.public class Test extends T1,T2{ public int x = 0; public Test(int x){ this. x = x; } }
D.protected class Test extends T2{ public int x = 0; public Test(int x) { this. x = x; } }
第16题:
有如下类定义: Class MyClass{ int value; public: MyClass(int n): value(n){} int getValue()const{return value;} }; 则类MyClass的构造函数的个数是
A.1个
B.2个
C.3个
D.4个
第17题:
下面程序段的输出结果为( )。 package test; public class ClassA { int x=20: static int y=6; public static void main(String args[]) { ClassB b=new ClassB; go(10); System.out.println("x="+b.x); } } class ClassB { int X; void go(int y) { ClassA a=new ClassA; x=a.Y ; } }
A.x=10
B.x=20
C.x=6
D.编译不通过
第18题:
在下列源代码文件Test.java中, ( )是正确的类定义。
A.public class test{
B.public class Test{ public int x=0;public int x=0; public test (intx) public Test (int x){ {this.x=x; this.x=x;} }} }
C.public class Test extends T1,T2{
D.protected class Test extends T2{ public int=0;public int x=0; public Test(int x){Public Test (int x){ this.x=x;this.x=x: }} }}
第19题:
给定java代码如下所示,在A处新增下列()方法,是对cal方法的重载。public class Test { public void cal(int x, int y, int z) { } //A }
第20题:
Given the following interface definition, which definitions are valid?() interface I { void setValue(int val); int getValue(); } DEFINITION a: (a) class a extends I { int value; void setValue(int val) { value = val; } int getValue() { return value; } } DEFINITION b: (b) interface b extends I { void increment(); } DEFINITION c: (c) abstract class c implements I { int getValue() { return 0; } abstract void increment(); } DEFINITION d: (d) interface d implements I { void increment(); } DEFINITION e: (e) class e implements I { int value; public void setValue(int val) { value = val; } }
第21题:
public class Foo { public int a; public Foo() { a = 3; } public void addFive() { a += 5; } } and: public class Bar extends Foo { public int a; public Bar() { a = 8; } public void addFive() { this.a +=5; } } invoked with: Foo foo = new Bar(); foo.addFive(); System.out.println(”Value: “+ foo.a); What is the result?()
第22题:
Value: 3
Value: 8
Value: 13
Compilation fails.
The code runs with no output.
An exception is thrown at runtime.
第23题:
Code marked with (1) is a constructor
Code marked with (2) is a constructor
Code marked with (3) is a constructor
Code marked with (4) is a constructor
Code marked with (5) is a Constructor
第24题:
Compilation fails.
ClassC is displayed.
The code runs with no output.
An exception is thrown at runtime.