现有:  class A  {public String name="a"}  class B extends A {p

题目
单选题
现有:  class A  {public String name="a"}  class B extends A {public String name="b"}      执行如下代码后的结果是哪项?()      A a=new B();  System.out.println(a.name);
A

  a

B

  b

C

编译失败

D

运行时抛出异常

参考答案和解析
正确答案: A
解析: 暂无解析
如果没有搜索结果或未解决您的问题,请直接 联系老师 获取答案。
相似问题和答案

第1题:

public class Pet{     private String name;     public Pet(String name){       this.name = name;    }  public void speak(){     System.out.print(name); }  }  public class Dog extends Pet{     public Dog(String name){       super(name);    }  public void speak(){    super.speak();  System.out.print(“ Dog ”);    } }  执行代码   Pet pet = new Dog(“京巴”);  pet.speak();  后输出的内容是哪项?() 

  • A、 京巴
  • B、 京巴 Dog
  • C、 null
  • D、 Dog京巴

正确答案:B

第2题:

public class Employee{   private String name;   public Employee(String name){   this.name = name;  }   public void display(){   System.out.print(name);  }  }   public class Manager extends Employee{   private String department;   public Manager(String name,String department){   super(name);   this.department = department;  }   public void display(){   System.out.println( super.display()+”,”+department);  }   }   执行语句new Manager(“smith”,”SALES”)后程序的输出是哪项?() 

  • A、 smith,SALES
  • B、 null,SALES
  • C、 smith,null
  • D、 null,null

正确答案:A

第3题:

package test;class Target{public String name="hello";}What can directly access and change the value of the variable name?()

A.any class

B.only the Target class

C.any class in the test package

D.any class that extends Target


参考答案:C

第4题:

public class Plant {  private String name;  public Plant(String name) { this.name = name; }  public String getName() { return name; }  }  public class Tree extends Plant {  public void growFruit() { }  public void dropLeaves() { }  }  Which is true?() 

  • A、 The code will compile without changes.
  • B、 The code will compile if public Tree() { Plant(); } is added to the Tree class.
  • C、 The code will compile if public Plant() { Tree(); } is added to the Plant class.
  • D、 The code will compile if public Plant() { this(”fern”); } is added to the Plant class.
  • E、 The code will compile if public Plant() { Plant(”fern”); } is added to the Plant class.

正确答案:D

第5题:

现有:  class A  {public String name="a"}  class B extends A {public String name="b"}      执行如下代码后的结果是哪项?()      A a=new B();  System.out.println(a.name);     

  • A、  a
  • B、  b
  • C、编译失败
  • D、运行时抛出异常

正确答案:A

第6题:

public class Employee{       private String name;  public Employee(String name){           this.name = name;      }  public String getName(){         return name;      } }  public class Manager extends Employee{       public Manager(String name){          System.out.println(getName());      } }  执行语句new Manager(“smith”)后程序的输出是哪项?() 

  • A、 smith
  • B、 null
  • C、 编译错误
  • D、 name

正确答案:C

第7题:

public class Pet{   private String name;   public Pet(){   System.out.print(1);  }   public Pet(String name){   System.out.print(2);  }   }   public class Dog extends Pet{  public Dog(String name){   //这里隐藏了一句代码:super.pet();   System.out.print(3);  }   }   执行new Dog(“棕熊”);后程序输出是哪项?() 

  • A、 23
  • B、 1 3
  • C、 123
  • D、 321

正确答案:B

第8题:

public class Pet{     private String name;     public Pet(){  System.out.print(1);    }  public Pet(String name){        System.out.print(2);    } }  public class Dog extends Pet{     public Dog(String name){        System.out.print(3);    } }  执行new Dog(“棕熊”);后程序输出是哪项?() 

  • A、 23
  • B、 13
  • C、 123
  • D、 321

正确答案:B

第9题:

public class Pet{   private String name;   public Pet(){   System.out.print(1);  }   public Pet(String name){   System.out.print(2);   }  }   public class Dog extends Pet{  public Dog(){   System.out.print(4);  }   public Dog(String name){   //这里隐藏了一句代码:super.pet();   this();   System.out.print(3);  }  }   执行new Dog(“棕熊”);后程序输出是哪项?() 

  • A、 143
  • B、 423
  • C、 243
  • D、 1134

正确答案:A

第10题:

Given the following code:     1) class Parent {     2) private String name;     3) public Parent(){}     4) }  5) public class Child extends Parent {     6) private String department;  7) public Child() {}  8) public String getValue(){ return name; }     9) public static void main(String arg[]) {     10) Parent p = new Parent();     11) }  12) }  Which line will cause error?()   

  • A、 line 3
  • B、 line 6
  • C、 line 7
  • D、 line 8
  • E、 line 10

正确答案:D

更多相关问题