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单选题现有:  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?()Apublic class Employee implements Info extends Data { public void load(){/*dosomething*/}     }B public class Employee extends 

题目
单选题
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?()
A

 public class Employee implements Info extends Data { public void load(){/*dosomething*/}     }

B

public class Employee extends Inf.implements Data{ public void load() {/*do something*/}     }

C

public class Empl.yee implements Inf extends Data{ public void Data.1oad(){* do something*/}     public void load(){/*do something*/}     }

D

public class Employee extends Inf implements Data  {  public void Data.1oad()  {/*do something*/)     public void info.1oad(){/*do something*/}    }


相似考题
更多“现有:  interface Data {public void load();}  abstract class In”相关问题
  • 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( ){};}


    正确答案:D
    Java中一个类是一个abstract类的子类,它必须具体实现父类的abstract方法。如果一个类中含有abstract方法,那么这个类必须用abstract来修饰(abstract类也可以没有abstract方法)。有abstract方法的父类只声明,由继承他的子类实现。所以选D。

  • 第2题:

    写出程序的输出结果

    public abstract class A

    {

    public A()

    {

    Console.WriteLine('A');

    }

    public virtual void Fun()

    {

    Console.WriteLine("A.Fun()");

    }

    }

    public class B: A

    {

    public B()

    {

    Console.WriteLine('B');

    }

    public new void Fun()

    {

    Console.WriteLine("B.Fun()");

    }

    public static void Main()

    {

    A a = new B();

    a.Fun();

    }

    }


    正确答案:
     

  • 第3题:

    下列哪个类声明是正确的? ( )

    A.abstract class G2 extends superClass1,superClass2{...}

    B.abstract public class classmates{...}

    C.public final class NewClass extends superClass implemnets Interface1{...}

    D.public abstract class String{...}


    正确答案:C
    解析:本题考查对类声明的掌握程度。选项A错误,Java不支持多重继承,故extends关键字后只能接一个父类;选项B错误,在类声明中public关键字必须位于abstract关键字前;选项C正确,声明了一个公有的不能继承的类,这个类的父类是superClass,并使用了Interfacel提供的接口,类不能声明为protected和pfivate属性且不以“;”结尾:选项D错误,String是Java中字符串的关键字,不能用于类名。

  • 第4题:

    以下语句能顺利通过编译: abstract class class1 { } public class mainClass { public static void main(String args[]) { class1 cs1=new class1(); } } 。()

    此题为判断题(对,错)。


    答案:错

  • 第5题:

    Which will declare a method that is available to all members of the same package and be referenced without an instance of the class?()

    • A、 abstract public void methoda ();
    • B、 public abstract double inethoda ();
    • C、 static void methoda (double dl) {}
    • D、 public native double methoda () {}
    • E、 protected void methoda (double dl) {}

    正确答案:C

  • 第6题:

    下列代码正确的是哪项?() 

    • A、 public class Session implements Runnable, Clonable{   public void run ();public Object clone () ; }
    • B、 public class Session extends Runnable, Cloneable {  public void run() {/*dosomething*/}       public Object clone() {/*make a copy*/} }
    • C、 public abstract class Session implements Runnable, Clonable {       public void run() {/*do something*/}       public Object clone() {/*make a copy*/}        }
    • D、 public class Session implements Runnable, implements Clonable {       public void run() {/*do something*/}       public Object clone() {/*make a copy*/}       }

    正确答案:C

  • 第7题:

    Which method must be defined by a class implementing the java.lang.Runnable interface? () 

    • A、 void run()
    • B、 public void run()
    • C、 public void start()
    • D、 void run(int priority)
    • E、 public void run(int priority)
    • F、 public void start(int priority)

    正确答案:B

  • 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?()

    • A、 public class Circle implements Shape { private int radius; }
    • B、 public abstract class Circle extends Shape { private int radius; }
    • C、 public class Circle extends Shape { private int radius; public void draw(); }
    • D、 public abstract class Circle implements Shape { private int radius; public void draw(); }
    • E、 public class Circle extends Shape { private int radius;public void draw() {/* code here */} }
    • F、 public abstract class Circle implements Shape { private int radius;public void draw() { / code here */ } }

    正确答案:B,E

  • 第9题:

    单选题
    下列代码正确的是哪项?()
    A

     public class Session implements Runnable, Clonable{   public void run ();public Object clone () ; }

    B

     public class Session extends Runnable, Cloneable {  public void run() {/*dosomething*/}       public Object clone() {/*make a copy*/} }

    C

     public abstract class Session implements Runnable, Clonable {       public void run() {/*do something*/}       public Object clone() {/*make a copy*/}        }

    D

     public class Session implements Runnable, implements Clonable {       public void run() {/*do something*/}       public Object clone() {/*make a copy*/}       }


    正确答案: A
    解析: 暂无解析

  • 第10题:

    单选题
    interface Data { public void load(); }  abstract class Info { public abstract void load(); }  Which class correctly uses the Data interface and Info class?()
    A

     public class Employee extends Info implements Data { public void load() { /*do something*/ } }

    B

     public class Employee implements Info extends Data { public void load() { /*do something*/ } }

    C

     public class Employee extends Info implements Data { public void load() { /*do something */ } public void Info.load() { /*do something*/ } }

    D

     public class Employee implements Info extends Data { public void Data.load() { /*dsomething */ } public void load() { /*do something */ } }

    E

     public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }

    F

     public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }


    正确答案: A
    解析: 暂无解析

  • 第11题:

    单选题
    Which will declare a method that is available to all members of the same package and can be referenced without an instance of the class?()
    A

     Abstract public void methoda();

    B

     Public abstract double methoda();

    C

     Static void methoda(double d1){}

    D

     Public native double methoda()  {}

    E

     Protected void methoda(double d1)  {}


    正确答案: C
    解析: 暂无解析

  • 第12题:

    单选题
    Which will declare a method that is available to all members of the same package and be referenced without an instance of the class?()
    A

     abstract public void methoda ();

    B

     public abstract double inethoda ();

    C

     static void methoda (double dl) {}

    D

     public native double methoda () {}

    E

     protected void methoda (double dl) {}


    正确答案: B
    解析: 暂无解析

  • 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();

    }

    }


    正确答案:

     

    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();


    正确答案:
    答:abstract override 是不可以一起修饰.
            }                                            // new public abstract void F();

  • 第15题:

    下列程序片段中,能通过编译的是( )。 A.public abstract class Animal{ public void speak;}S

    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{};}


    正确答案:A
    A。【解析】Java中一个类是一个abstract类的子类,它必须具体实现父类的abstract方法。如果一个类中含有abstract方法,那么这个类必须用abstract来修饰(abstract类也可以没有abstract方法)。有abstract方法的父类只声明,由继承它的子类实现。所以选A。

  • 第16题:

    Which will declare a method that is available to all members of the same package and can be referenced  without an instance of the class?()  

    • A、 Abstract public void methoda();
    • B、 Public abstract double methoda();
    • C、 Static void methoda(double d1){}
    • D、 Public native double methoda(){}
    • E、 Protected void methoda(double d1){}

    正确答案:C

  • 第17题:

    interface Data { public void load(); }  abstract class Info { public abstract void load(); }  Which class correctly uses the Data interface and Info class?() 

    • A、 public class Employee extends Info implements Data { public void load() { /*do something*/ } }
    • B、 public class Employee implements Info extends Data { public void load() { /*do something*/ } }
    • C、 public class Employee extends Info implements Data { public void load() { /*do something */ } public void Info.load() { /*do something*/ } }
    • D、 public class Employee implements Info extends Data { public void Data.load() { /*dsomething */ } public void load() { /*do something */ } }
    • E、 public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }
    • F、 public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }

    正确答案:A

  • 第18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; }  }  

    • A、Definition a.
    • B、Definition b.
    • C、Definition c.
    • D、Definition d.
    • E、Definition e.

    正确答案:B,C

  • 第19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?() 

    • A、 public class Employee implements Info extends Data { public void load(){/*dosomething*/}     }
    • B、public class Employee extends Inf.implements Data{ public void load() {/*do something*/}     }
    • C、public class Empl.yee implements Inf extends Data{ public void Data.1oad(){* do something*/}     public void load(){/*do something*/}     }
    • D、public class Employee extends Inf implements Data  {  public void Data.1oad()  {/*do something*/)     public void info.1oad(){/*do something*/}    }

    正确答案:B

  • 第20题:

    单选题
    Which method must be defined by a class implementing the java.lang.Runnable interface? ()
    A

     void run()

    B

     public void run()

    C

     public void start()

    D

     void run(int priority)

    E

     public void run(int priority)

    F

     public void start(int priority)


    正确答案: E
    解析: 暂无解析

  • 第21题:

    单选题
    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?()
    A

     public class Employee implements Info extends Data { public void load(){/*dosomething*/}     }

    B

    public class Employee extends Inf.implements Data{ public void load() {/*do something*/}     }

    C

    public class Empl.yee implements Inf extends Data{ public void Data.1oad(){* do something*/}     public void load(){/*do something*/}     }

    D

    public class Employee extends Inf implements Data  {  public void Data.1oad()  {/*do something*/)     public void info.1oad(){/*do something*/}    }


    正确答案: D
    解析: 暂无解析

  • 第22题:

    多选题
    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?()
    A

    public class Circle implements Shape { private int radius; }

    B

    public abstract class Circle extends Shape { private int radius; }

    C

    public class Circle extends Shape { private int radius; public void draw(); }

    D

    public abstract class Circle implements Shape { private int radius; public void draw(); }

    E

    public class Circle extends Shape { private int radius;public void draw() {/* code here */} }

    F

    public abstract class Circle implements Shape { private int radius;public void draw() { / code here */ } }


    正确答案: B,E
    解析: 暂无解析

  • 第23题:

    单选题
    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?()
    A

    0

    B

    1

    C

    2

    D

    3


    正确答案: D
    解析: 暂无解析

  • 第24题:

    单选题
    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:()
    A

    1

    B

    2

    C

    3

    D

    4


    正确答案: C
    解析: 暂无解析