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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

参考答案

更多 “ 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,SALESB、 null,SALESC、 smith,nullD、 null,null” 相关考题
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考题 执行以下代码后,下面哪些描述是正确的() public  class  Student{  private String name = “Jema”;  public void setName(String name){  this.name = name;  }  public String getName(){  return this.name;  }  public static void main(String[] args){  Student s;  System.out.println(s.getName()); } }A、输出nullB、第10行编译报错C、第11行编译报错D、输出Jema

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考题 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、 143B、 423C、 243D、 1134

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考题 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 3B、 line 6C、 line 7D、 line 8E、 line 10

考题 11. class Person {  12. String name = “No name‟;  13. public Person(String nm) { name = nm; }  14. }  15.  16. class Employee extends Person {  17. String emplD = “0000”;  18. public Employee(String id) { empID = id; }  19. }  20.  21. public class EmployeeTest {  22. public static void main(String[] args) {  23. Employee e = new Employee(”4321”);  24. System.out.println(e.empID);  25. }  26. }  What is the result?() A、 4321B、 0000C、 An exception is thrown at runtime.D、 Compilation fails because of an error in line 18.

考题 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){        this();  System.out.print(3);    } }  执行new Dog(“棕熊”);后程序输出是哪项?()  A、 143B、 423C、 243D、 1134

考题 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、 smithB、 nullC、 编译错误D、 name

考题 public class NamedCounter {  private final String name;  private int count;  public NamedCounter(String name) { this.name = name; }  public String getName() { return name; }  public void increment() { coount++; }  public int getCount() { return count; } public void reset() { count = 0; } }  Which three changes should be made to adapt this class to be used safely by multiple threads? ()A、 declare reset() using the synchronized keywordB、 declare getName() using the synchronized keywordC、 declare getCount() using the synchronized keywordD、 declare the constructor using the synchronized keywordE、 declare increment() using the synchronized keyword

考题 单选题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){        this();  System.out.print(3);    } }  执行new Dog(“棕熊”);后程序输出是哪项?()A  143B  423C  243D  1134

考题 单选题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  23B  13C  123D  321

考题 单选题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,SALESB  null,SALESC  smith,nullD  null,nullE  编译错误

考题 单选题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.

考题 单选题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  smithB  nullC  编译错误D  name

考题 单选题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 3B  line 6C  line 7D  line 8E  line 10

考题 单选题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 DogC  nullD  Dog京巴

考题 单选题执行以下代码后,下面哪些描述是正确的() public  class  Student{  private String name = “Jema”;  public void setName(String name){  this.name = name;  }  public String getName(){  return this.name;  }  public static void main(String[] args){  Student s;  System.out.println(s.getName()); } }A 输出nullB 第10行编译报错C 第11行编译报错D 输出Jema

考题 单选题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  23B  1 3C  123D  321