单选题类Teacher: class Teacher{   String name; float salary;  Teacher(String name){    this.name = name; }  Teacher(String name,float salary){   this.name = name;    this.salary = salary; } }  执行语句Teacher t = new Teacher(“Tom”,2000.0f);后,字段salary的值是哪一项?()A200

题目
单选题
类Teacher: class Teacher{   String name; float salary;  Teacher(String name){    this.name = name; }  Teacher(String name,float salary){   this.name = name;    this.salary = salary; } }  执行语句Teacher t = new Teacher(“Tom”,2000.0f);后,字段salary的值是哪一项?()
A

 2000.0f

B

 0.0f

C

 null;

D

 2000


相似考题

1.阅读以下说明和java代码,将应填入(n)处的字句写在对应栏内。[说明]有若干教师,每个教师只有姓名,一个教师可以指导多名研究生;每名研究生有姓名和研究方向,程序最后输出每个教师指导的所有研究生的姓名和研究方向。[Java程序]public class Teacher {String name;int top=0;Student[] student=new Student[20];public Teacher() {}public Teacher(String name) { this.name=name;}boolean add(Student stu){int len=this.student.length;if (top<len-1) {this.student[top]=siu;(1);return true;}elsereturn (2);}void disp(){System.out.println(“指导老师"”+this.name);System.out.println(“研究生:”);for(int i=0;i<(3);i++){System.out.println(“姓名:”+this.student[i].name+“\t研究方向:”+this.student[i]. search);}}public static void main(String[] args){Teacher t[]={new Teacher(“李明”),new Teacher(“王华”)};Student s1 = new Student(“孙强”,“数据库”);Student s2 = new Student(“陈文”,“软件工程”);Student s3 = new Student(“章锐”,“计算机网络”);if(! t[0].add(s1)) {System.out.println(“每个老师最多只能指导20个学生!”);}if(! t[0].add(a2)) {System.out.println(“每个老师最多只能指导20个学生!”);}if(! t[1].add(s3)) {System.out.println(“每个老师最多只能指导20个学生!”);}for(int i=0;i<2;i++)(4);}}class (5) {String name;String search;public Student(){}public Student(String name,String search){this.name=name;this.search=search;}String getName(){return this.name;}String getSearch(){return this.search;}}

2.阅读以下说明和Java代码,将应填入(n)处的字句写在对应栏内。[说明]本程序的功能是给公司的员工Tom,Jack,Green增加薪水。三人的职位分别是programmer, Manager,CEO。程序由6个类组成:WorkerTest是主类,programmer,Manager,CEO三个类,薪水增加的规则是 programmer的涨幅是5%;Manager的是10%;CEO也是Manager,但是它除了有Manager的涨幅,还有1000元的bonus。接口SalaryRaise提供了一个增加薪水的方法raise()。[java程序]public class WorkerTest {public WorkerTest( ) {}public static void main( String[] args) {Programmer programmer = new Programmer( "Tom" ,3000);Manager manager = new Manager( "Jack" ,4000);CEO ceo = new CEO( "Green" ,4000);Worker [] worker = new Worker[3];programmer, raise( );manager, raise( );ceo. raise( );worker[0] = programmer;worker [1] = manager;worker[2] = ceo;for ( int i = 0 ;i < worker, length; i + + ) {System. out. prinfln (" Name:" + worker [i]. getName ( ) +" \ tSalary:" + worker [i]. getSalary ());public interface SalaryRaise { void raise( ); }public class Worker {public String name;public double (1);public Worker( ) {}public String getName( ) {return name;}public void setName( String name) {this. name = name;}public double getSalary( ) {return salary;}public void setSalary(double salary) { this. salary = salary; }}public class Programmer extends Worker implements (2) {public Programmer( ) {}public void raise( ) {double pets=0.05;double sala = this. getSalary( ) * (1 + pers);this. setSalary (sala);public Programmer( Siring name, double salary) tthis. name = name;this. salary = salary;public class Manager extends (3) implements SalaryRaise {public Manager( ) { }public Manager(String name, double salary) {this. name = name;this. salary = salary;}public void raise( ) {double pets = 0.1;double sala = this. getSalary() * (1 + pers);this. setSalary(sala);}}public class CEO extends Manager implements SalaryRaise {public CEO() {}public CEO( String name,double salary) {this. name = name;this. salary = salary;}public void raise( ) {double bonus = 1000;(4);double sala = this. getSalary( );(5);this. setSalary(sala);}}

更多“单选题类Teacher: class Teacher{   String name; float salary;  Teacher(String name){    this.name = name; }  Teacher(String name,float salary){   this.name = name;    this.salary = salary; } }  执行语句Teacher t = new Teacher(“Tom”,2000.0f);后,字段salary的值是哪一项?()A  2”相关问题
  • 第1题:

    interface Playable {

    void play();

    }

    interface Bounceable {

    void play();

    }

    interface Rollable extends Playable, Bounceable {

    Ball ball = new Ball("PingPang");

    }

    class Ball implements Rollable {

    private String name;

    public String getName() {

    return name;

    }

    public Ball(String name) {

    this.name = name;

    }

    public void play() {

    ball = new Ball("Football");

    System.out.println(ball.getName());

    }

    }

    这个错误不容易发现。


    正确答案:

     

    错。"interface Rollable extends Playable, Bounceable"没有问题。interface 可继承多个

    interfaces,所以这里没错。问题出在interface Rollable 里的"Ball ball = new Ball("PingPang");"。

    任何在interface 里声明的interface variable (接口变量,也可称成员变量),默认为public static

    final。也就是说"Ball ball = new Ball("PingPang");"实际上是"public static final Ball ball = new

    Ball("PingPang");"。在Ball 类的Play()方法中,"ball = new Ball("Football");"改变了ball 的

    reference,而这里的ball 来自Rollable interface,Rollable interface 里的ball 是public static final

    的,final 的object 是不能被改变reference 的。因此编译器将在"ball = new Ball("Football");"

    这里显示有错。

  • 第2题:

    试题六(共15分)

    阅读以下说明和Java代码,填补Java代码中的空缺(1)~(6),将解答写在答题纸的对应栏内。

    【说明】

    己知某公司按周给员工发放工资,其工资系统需记录每名员工的员工号、姓名、工资等信息。其中一些员工是正式的,按年薪分周发放(每年按52周计算);另一些员工是计时工,以小时工资为基准,按每周工作小时数核算发放。

    下面是实现该工资系统的Java代码,其中定义了四个类:工资系统类PayRoll,员工类Employee,正式工类Salaried和计时工类Hourly,Salaried和Hourly是Employee的子类。

    【Java代码】

    abstract class Employee{

    protected String name; //员工姓名

    protected int empCode; //员工号

    protected double salary; //周发放工资

    public Employee(int empCode, String name){

    this.empCode= empCode;

    this.name= name;

    }

    public double getSalary(){

    return this.salary;

    }

    public abstract void pay();

    }

    class Salaried (1) Employee{

    private double annualSalary;

    Salaried(int empCode, String name, double payRate){

    super(empCode, name);

    this.annualSalary= payRate;

    }

    public void pay(){

    salary= (2) ;//计算正式员工的周发放工资数

    System.out.println(this.name+":"+this.salary);

    }

    }

    class Hourly (3) Employee{

    private double hourlyPayRate;

    private int hours;

    Hourly(int empCode, String name, int hours, double payRate){

    super(empCode, name);

    this.hourlyPayRate= payRate;

    this.hows= hours,

    }

    public void pay(){

    salary= (4) ;//计算计时工的周发放工资数

    System.out.println(this.name+":"+this.salary);

    }

    }

    public class PayRoll{

    private (5) employees[]={

    new Salaried(l001,"Zhang San", 58000.00),

    //此处省略对其他职工对象的生成

    new Hourly(1005,"Li", 12, 50.00)

    };

    public void pay(Employee e[]){

    for (int i=0;i<e.length; i++){

    e[i].pay();

    }

    }

    public static void main(String[] args)

    {

    PayRoll payRoll= new PayRoll();

    payRoll.pay( (6) );

    double total= 0.0;

    for (int i=0;i<payRoll.employees.length; i++){//统计周发放工资总额

    total+=payRoll.employees[i].getSalary();

    }

    System.out.println(total);

    }

    }


    正确答案:
    (1)extends
    (2)annualSalary/52
    (3)extends
    (4)hours*hourlyPayRate
    (5)~(6)的解答可为以下两种之一:
    (5)Employee
    (6)payRoll.employees

    (5)staticEmployee
    (6)employees或payRoll.employees

  • 第3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null
    • B、第10行编译报错
    • C、第11行编译报错
    • D、输出Jema

    正确答案:C

  • 第4题:

    类Student代码如下:  class Student{    String name;  int age;  Student(String nm){  name = nm; } }  执行语句Student stu = new Student()后,字段age的值是哪项?() 

    • A、 0
    • B、 null
    • C、 false
    • D、 编译错误

    正确答案:D

  • 第5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{       private String department;  public Manager(String name,String department){          this.department = department;          super(name);  System.out.println(getName());      }  }  执行语句new Manager(“smith”,”SALES”)后程序的输出是哪项?() 

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

    正确答案:D

  • 第7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8题:

    单选题
    类Teacher:  class Teacher{   String name;   float salary;   Teacher(String name){   this.name = name;  }   Teacher(String name,float salary){   this.name = name;   this.salary = salary;  }  }   执行语句Teacher t = new Teacher(“Tom”,2000.0f);后,字段salary的值是哪一项?()
    A

     2000.0f

    B

     0.0f

    C

     null;

    D

     2000


    正确答案: C
    解析: 暂无解析

  • 第9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{       private String department;  public Manager(String name,String department){          this.department = department;          super(name);  System.out.println(getName());      }  }  执行语句new Manager(“smith”,”SALES”)后程序的输出是哪项?()
    A

     smith

    B

     null

    C

     SALES

    D

     编译错误


    正确答案: C
    解析: 暂无解析

  • 第10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,SALES

    B

     null,SALES

    C

     smith,null

    D

     null,null


    正确答案: A
    解析: 暂无解析

  • 第11题:

    单选题
    Tony’s salary as a plumber is much higher than _____.
    A

    a teacher

    B

    a teacher has

    C

    that of a teacher does

    D

    that of a teacher


    正确答案: A
    解析:
    句意:作为水管工人,Tony的工资远比教师的工资要高。that指代the salary,与前面Tony’s salary相对应。比较级比较的是二者的工资,而不是“Tony的工资”和“教师”,故排除选项A。

  • 第12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null

    B

    第10行编译报错

    C

    第11行编译报错

    D

    输出Jema


    正确答案: D
    解析: 暂无解析

  • 第13题:

    Person p = new Person(“张三”,23);这条语句会调用下列哪个构造方法给属性进行初始化()

    A.public Person(){}

    B.public Person(String name,int age) { this.name = name; this.age = age; }

    C.public Person(int age,String name) { this.age = age; this.name = name; }

    D.public Person(String name) { this.name = name; }


    答案:B
    解析:创建对象时会找到匹配的构造方法给属性进行初始化,由于Person p = new Person(“张三”,23);这条语句中有两个参数,而且第1个参数是String类型的,第2个参数是int类型的,因此会调用B选项中的构造方法。

  • 第14题:

    The salary of an engineer is much higher__.

    A.than a teacher
    B.than that of a teacher
    C.in comparison with a teacher's
    D.than of a teacher's

    答案:B
    解析:
    that替代的是不可数名词salary。

  • 第15题:

    类Teacher:  class Teacher{   String name;   float salary;   Teacher(String name){   this.name = name;  }   Teacher(String name,float salary){   this.name = name;   this.salary = salary;  }  }   执行语句Teacher t = new Teacher(“Tom”,2000.0f);后,字段salary的值是哪一项?() 

    • A、 2000.0f
    • B、 0.0f
    • C、 null;
    • D、 2000

    正确答案:A

  • 第16题:

    public class Employee{   private String name;   public Employee(String name){   this.name = name;  }   public String getName(){   return name;  }  }   public class Manager extends Employee{   private String department;   public Manager(String name,String department){   this.department = department;   super(name); (应于上一行掉位置)   System.out.println(getName());  }  }   Super的位置是否在方法的首行   执行语句new Manager(“smith”,”SALES”)后程序的输出是哪项?()

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

    正确答案:D

  • 第17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
    • E、 编译错误

    正确答案:E

  • 第18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19题:

    单选题
    Tony’s salary as a plumber is much higher than ______.
    A

    a teacher  

    B

    a teacher has

    C

    that of a teacher does

    D

    that of a teacher


    正确答案: B
    解析:
    作为水管工人,Tony的工资远比教师的工资要高。that指代the salary,与前面Tony’s salary相对应。比较级比较的是二者的工资,而不是“Tony的工资”和“教师”,故排除选项A。

  • 第20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,SALES

    B

     null,SALES

    C

     smith,null

    D

     null,null

    E

     编译错误


    正确答案: C
    解析: 暂无解析

  • 第21题:

    单选题
    类Student代码如下:  class Student{    String name;  int age;  Student(String nm){  name = nm; } }  执行语句Student stu = new Student()后,字段age的值是哪项?()
    A

     0

    B

     null

    C

     false

    D

     编译错误


    正确答案: D
    解析: 暂无解析

  • 第22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

     smith

    B

     null

    C

     编译错误

    D

     name


    正确答案: B
    解析: 暂无解析

  • 第23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 Dog

    C

     null

    D

     Dog京巴


    正确答案: B
    解析: 暂无解析

  • 第24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{   private String department;   public Manager(String name,String department){   this.department = department;   super(name); (应于上一行掉位置)   System.out.println(getName());  }  }   Super的位置是否在方法的首行   执行语句new Manager(“smith”,”SALES”)后程序的输出是哪项?()
    A

     smith

    B

     null

    C

     SALES

    D

     编译错误


    正确答案: C
    解析: 暂无解析