Compilation is successful.
An error on line 6 causes a runtime failure.
An error at line 6 causes compilation to fail.
An error at line 2 causes compilation to fail.
第1题:
下列哪个类声明是正确的?
A.abstract class G2 extends superClassl,superClass2{……}
B.abstract public class classmates{……}
C.public final class NewClass extends superClass implements Interfacel{……}
D.public abstract class String{……}
第2题:
如果有-个类MyFrame是Frame的子类,但它不能被实例化,请写出该类的声明头为( )。
A.abstract class Frame. extends MyFrame
B.abstract class MyFrame. extends Frame
C.class MyFrame. abstract extends Frame
D.class Frame. abstract extends MyFrame.
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{ public abstract void speak();}
D.public abstract class Animal{ public abstract void speak(){}}
第4题:
如果有一个类MyFrame是Frame的子类,但它不能被实例化,请写出该类的声明头为( )。
A.abstract class Frame. extends MyFrame
B.abstract class MyFrame. extends Frame
C.class MyFrame. abstract extends Frame
D.class Frame. abstract extends MyFrame.
第5题:
abstract class Something {
private abstract String doSomething ();
}
这好像没什么错吧?
错。abstract 的methods 不能以private 修饰。abstract 的methods 就是让子类implement(实
现)具体细节的,怎么可以用private 把abstract
method 封锁起来呢? (同理,abstract method 前不能加final)。
第6题:
A.
B.
C.
D.
E.
F.
第7题:
Java代码查错
1.
abstract class Name {
private String name;
public abstract boolean isStupidName(String name) {}
}
大侠们,这有何错误?
错。abstract method 必须以分号结尾,且不带花括号。
第8题:
下列哪个类声明是正确的? ( )
A.abstract final class H1 {...}
B.abstract private move(){...}
C.protected private number
D.public abstract class Car{...}
第9题:
下列对类的声明,正确的是( ) B
A.abstract final class Hh{…}
B.abstract private move(){…}
C.protected private number;
D.public abstract class Car{…}
第10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();