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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null
  • B、第10行编译报错
  • C、第11行编译报错
  • D、输出Jema

参考答案

更多 “ 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” 相关考题
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考题 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,null

考题 声明Java独立应用程序main()方法时,正确表达是()。A、public static void main(String[]args){…}B、private static void main(String args[]){…}C、public void main(String args[]){…}D、public static void main(){…}

考题 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 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 下面哪些main方法可用于程序执行()A、public static void main(String[]args)B、public static void main(String[]x)C、public static void main(Stringargs[])D、public void main(String[]args)

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 单选题下面哪些选项是正确的main方法说明?()A  public main(String args[])B  public static void main(String args[])C  private static void main(String args[])D  void main()