public class Employee extends Info implements Data { public void load() { /*do something*/ } }
public class Employee implements Info extends Data { public void load() { /*do something*/ } }
public class Employee extends Info implements Data { public void load() { /*do something */ } public void Info.load() { /*do something*/ } }
public class Employee implements Info extends Data { public void Data.load() { /*dsomething */ } public void load() { /*do something */ } }
public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }
public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }
第1题:
下列程序片段中,能通过编译的是( )。
A.public abstract class Animal{public void speak( );}
B.public abstract class Animal{public void speak( ){};}
C.public class Animal{pubilc abstract void speak( );}
D.public abstract class Animal{pubile abstract void speak( ){};}
第2题:
下面程序输出的结果是【 】。
include <iostream>
using namespace std;
class A {
public:
virtual void show() {cout<<"A!";
};
class B: public A {
public:
void show() {cout << "B!";}
};
class C: public B{
public:
void show(){cout << "C!";}
};
void show_info(A &i) {i. show();}
void main() {
A ia; B ib; C ic; show_info(ia);show_info(ib); show_info(ic); }
第3题:
下列程序片段中,能通过编译的是( )。
A.public abstract class Animal{ public void speak;}
B.public abstract class Animal{ public void speak{);}
C.public class Animal{ pubilc abstract void speak;}
D.public abstract class Animal{ pubile abstract void speak{};}
第4题:
interface Data { public void load(); } abstract class Info { public abstract void load(); } Which class correctly uses the Data interface and Info class?()
第5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6题:
现有: interface Data {public void load();} abstract class Info {public abstract void load();} 下列类定义中正确使用Data和Info的是哪项?()
第7题:
Which two demonstrate an “is a” relationship?()
第8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9题:
public class Session implements Runnable, Clonable{ public void run ();public Object clone () ; }
public class Session extends Runnable, Cloneable { public void run() {/*dosomething*/} public Object clone() {/*make a copy*/} }
public abstract class Session implements Runnable, Clonable { public void run() {/*do something*/} public Object clone() {/*make a copy*/} }
public class Session implements Runnable, implements Clonable { public void run() {/*do something*/} public Object clone() {/*make a copy*/} }
第10题:
0
1
2
3
第11题:
public class Circle implements Shape { private int radius; }
public abstract class Circle extends Shape { private int radius; }
public class Circle extends Shape { private int radius; public void draw(); }
public abstract class Circle implements Shape { private int radius; public void draw(); }
public class Circle extends Shape { private int radius;public void draw() {/* code here */} }
public abstract class Circle implements Shape { private int radius;public void draw() { / code here */ } }
第12题:
public class Employee implements Info extends Data { public void load(){/*dosomething*/} }
public class Employee extends Inf.implements Data{ public void load() {/*do something*/} }
public class Empl.yee implements Inf extends Data{ public void Data.1oad(){* do something*/} public void load(){/*do something*/} }
public class Employee extends Inf implements Data { public void Data.1oad() {/*do something*/) public void info.1oad(){/*do something*/} }
第13题:
interface A{
int x = 0;
}
class B{
int x =1;
}
class C extends B implements A {
public void pX(){
System.out.println(x);
}
public static void main(String[] args) {
new C().pX();
}
}
错误。在编译时会发生错误(错误描述不同的JVM 有不同的信息,意思就是未明确的
x 调用,两个x 都匹配(就象在同时import java.util 和java.sql 两个包时直接声明Date 一样)。
对于父类的变量,可以用super.x 来明确,而接口的属性默认隐含为 public static final.所以可
以通过A.x 来明确。
第14题:
下面的代码中有什么错误吗?_______
using System;
class A
{
public virtual void F(){
Console.WriteLine("A.F");
}
}
abstract class B:A
{
public abstract override void F();
第15题:
Which three demonstrate an “is a” relationship?()
第16题:
下列代码正确的是哪项?()
第17题:
现有: interface Animal { void eat () ; } //insert code here public class HouseCat extends Feline { public void eat() { } } 和五个申明 abstract class Feline implements Animal { } abstract class Feline implements Animal { void eat () ; } abstract class Feline implements Animal { public void eat();} abstract class Feline implements Animal { public void eat() {} } abstract class Feline implements Animal { abstract public void eat();} 结果为:()
第18题:
Which the two demonstrate an “is a” relationship?()
第19题:
现有: 1. interface Animal { 2. void eat(); 3. } 4. 5. // insert code here 6. 7. public class HouseCat extends Feline { 8. public void eat() { } 9. } 和五个声明: abstract class Feline implements Animal { } abstract class Feline implements Animal { void eat(); } abstract class Feline implements Animal { public void eat(); } abstract class Feline implements Animal { public void eat() { } } abstract class Feline implements Animal { abstract public void eat(); } 分别插入到第5行,有几个可以通过编译?()
第20题:
public interface Person { } public class Employee extends Person { }
public interface Shape { } public class Employee extends Shape { }
public interface Color { } public class Employee extends Color { }
public class Species { } public class Animal (private Species species;)
interface Component { } Class Container implements Component ( Private Component[ ] children; )
第21题:
public interface Person {} Public class Employee extends Person {}
public interface Shape {} public interface Rectangle extends Shape {}
public interface Color {} public class Shape { private Color color; }
public class Species {} public class Animal { private Species species; }
interface Component {} Class Container implements Component {private Component [] children;
第22题:
public class X { } public class Y extends X { }
public interface Shape { } public interface Rectangle extends Shape{ }
public interface Color { } public class Shape { private Color color; }
public interface Species { } public class Animal { private Species species; }
public class Person { } public class Employee { public Employee(Person person) { }
interface Component { } class Container implements Component { private Component[] children; }
第23题:
public class Employee extends Info implements Data { public void load() { /*do something*/ } }
public class Employee implements Info extends Data { public void load() { /*do something*/ } }
public class Employee extends Info implements Data { public void load() { /*do something */ } public void Info.load() { /*do something*/ } }
public class Employee implements Info extends Data { public void Data.load() { /*dsomething */ } public void load() { /*do something */ } }
public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }
public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }
第24题:
1
2
3
4