class Guy{String greet(){return “hi“}}   class Cowboy extends Guy {String greet(){return“howdy”}}   class Surfer extends Guy {String greet(){return“dudel”}}  class Greetings{   public static void main (string[]args){   Guy[] guy= {new Guy(),new Cowboy(),new Surfer()};   for(Guy 0: guys)   System.out.print(g.green());  }   }   结果为:  A、运行时异常被输出B、第7行出现一个错误,编译失败C、第8行出现一个错误,编译失败D、hi hi hiE、hi hawdy doude

class Guy{String greet(){return “hi“}}   class Cowboy extends Guy {String greet(){return“howdy”}}   class Surfer extends Guy {String greet(){return“dudel”}}  class Greetings{   public static void main (string[]args){   Guy[] guy= {new Guy(),new Cowboy(),new Surfer()};   for(Guy 0: guys)   System.out.print(g.green());  }   }   结果为:  

  • A、运行时异常被输出
  • B、第7行出现一个错误,编译失败
  • C、第8行出现一个错误,编译失败
  • D、hi hi hi
  • E、hi hawdy doude

相关考题:

You have recently created a serializable class named Vehicle.The class is shown below:[Serializable]public class Vehicle{public string VIN;public string Make;public string Model;public string Year;}You are planning to create a custom formatter class to control the formatting of Vehicle objects when they are serialized.You need to ensure that is achieved with as little development effort as possible.What should you do?()A.B.C.D.

classGuy{Stringgreet(){returnhi}}classCowboyextendsGuy{Stringgreet(){returnhowdy”}}classSurferextendsGuy{Stringgreet(){returndudel”}}classGreetings{publicstaticvoidmain(string[]args){Guy[]guy={newGuy(),newCowboy(),newSurfer()};for(Guy0:guys)System.out.print(g.green());}}结果为:A.运行时异常被输出B.第7行出现一个错误,编译失败C.第8行出现一个错误,编译失败D.hihihiE.hihawdydoude

Part of the signature of the String class is:class String {....};Other part of signature and implementation is completed by you.

4 . 写出程序的输出结果class Class1 {private string str = "Class1.str";private int i = 0;static void StringConvert(string str) {str = "string being converted.";}static void StringConvert(Class1 c) {c.str = "string being converted.";}static void Add(int i) {i++;}static void AddWithRef(ref int i) {i++;}static void Main() {int i1 = 10;int i2 = 20;string str = "str";Class1 c = new Class1();Add(i1);AddWithRef(ref i2);Add(c.i);StringConvert(str);StringConvert(c);Console.WriteLine(i1);Console.WriteLine(i2);Console.WriteLine(c.i);Console.WriteLine(str);Console.WriteLine(c.str);}}

已知类 String 的原型为class string{public:string(const char *str=null);//普通构造函数string(const string other);//拷贝构造函数---string(void);string operate=(const string other);//赋值函数private:char * m-data;//用于保存字符串};请编写 string 的上述4 个函数

类Account中字段声明正确的是?()    A、class Account{  name;  amount;  }B、class Account{  String name;  double amount;  }C、class Account{  String name=1.0;  double amount=”Mike”;  }D、class Account{  String name=”Mike”,double amount=1000.0;  }

Which statements concerning the following code are true?()   class a {   public a() {}   public a(int i) { this(); }   }   class b extends a {   public boolean b(String msg) { return false; }   }   class c extends b  {  private c() { super(); }   public c(String msg) { this(); }   public c(int i) {}   }  A、The code will fail to compile.B、The constructor in a that takes an int as an argument will never be called as a result of constructing an  object of class b or c.C、Class c has three constructors.D、Objects of class b cannot be constructed.E、At most one of the constructors of each class is called as a result of constructing an object of class c.

Which two allow the class Thing to be instantiated using new Thing()?A、 public class Thing { }B、 public class Thing { public Thing() {} }C、 public class Thing { public Thing(void) {} }D、 public class Thing { public Thing(String s) {} }E、 public class Thing { public void Thing() {} public Thing(String s) {} }

class Mineral {   static String shiny() { return "1"; }   }   class Granite extends Mineral {   public static void main(String [] args) {   String s = shiny() + getShiny();   s = s + super.shiny();   System.out.println(s);   }   static String getShiny() { return shiny(); }   }   结果为:()  A、3B、12C、111D、编译失败

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

现有:  class Guy {String greet()    {return "hi";  }  }  class Cowboy extends Guy  (  String greet()    (  return "howdy  ¨;    )  )  class Surfer extends Guy  (String greet()    (return "dude! ";)) class Greetings  {  public static void main (String  []  args)    {  Guy  []  guys =  ( new Guy(), new Cowboy(), new Surfer()  );  for (Guy g:  guys) System.out.print (g.greet()};  }  }  结果为:() A、 hi howdy dude!B、运行时异常被抛出。C、第7行出现一个错误,编译失败。D、第8行出现一个错误,编译失败。

Which methods from the String and StringBuffer classes modify the object on which they are called?()  A、The charAt() method of the String class.B、The toUpperCase() method of the String class.C、The replace() method of the String class.D、The reverse() method of the StringBuffer class.E、The length() method of the StringBuffer class.

我们定义一个Account类来描述银行账户,银行账户有账户名、金额等属性特征,同时有存款、取款等行为特征,下述代码适合描述的是哪项?()     A、class  Accountf      String name;//账户     S tring amount;  //金额      Account (String name)(    ) void deposit (double mount){  //存款     ) void withdraw (double mount){  //取款     }     )B、class  Accountf      String name;//账户d ouole amount;  //金额      Account(double amount){   } void deposit (double mount){  //存款     ) void withdraw (double mount){  //取款     )     )C、class  Accountf      String name;//账户 double amount;  //金额      Account (String name){} void deposit (double mount){//存款     )  void withdraw (double mount){  //取款     )     )D、class Accountf      String name;//账户      double amount;//金额      Account (String name){}      void deposit(){//存款     )  void withdraw(){//取款 )     )

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.

You work as the application developer at Hi-Tech.com. You create a new custom dictionary named MyDictionary. Choose the code segment which will ensure that MyDictionary is type safe?()A、 Class MyDictionary Implements Dictionary (Of String,String)B、 Class MyDictionary Inherits HashTableC、 Class MyDictionary Implements IDictionaryD、 Class MyDictionary End Class Dim t as New Dictionary (Of String, String) Dim dict As MyDIctionary= CType (t,MyDictionary)

多选题Which declarations will allow a class to be started as a standalone program?()Apublic void main(String args[])Bpublic void static main(String args[])Cpublic static main(String[] argv)Dfinal public static void main(String [] array)Epublic static void main(String args[])

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 smithB nullC SALESD 编译错误

单选题class Guy{String greet(){return “hi“}}   class Cowboy extends Guy {String greet(){return“howdy”}}   class Surfer extends Guy {String greet(){return“dudel”}}  class Greetings{   public static void main (string[]args){   Guy[] guy= {new Guy(),new Cowboy(),new Surfer()};   for(Guy 0: guys)   System.out.print(g.green());  }   }   结果为:A运行时异常被输出B第7行出现一个错误,编译失败C第8行出现一个错误,编译失败Dhi hi hiEhi hawdy doude

单选题You work as the application developer at Hi-Tech.com. You create a new custom dictionary named MyDictionary. Choose the code segment which will ensure that MyDictionary is type safe?()A Class MyDictionary Implements Dictionary (Of String,String)B Class MyDictionary Inherits HashTableC Class MyDictionary Implements IDictionaryD Class MyDictionary End Class Dim t as New Dictionary (Of String, String) Dim dict As MyDIctionary= CType (t,MyDictionary)

单选题Which methods from the String and StringBuffer classes modify the object on which they are called?()AThe charAt() method of the String class.BThe toUpperCase() method of the String class.CThe replace() method of the String class.DThe reverse() method of the StringBuffer class.EThe length() method of the StringBuffer class.

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

多选题Which two allow the class Thing to be instantiated using new Thing()?Apublic class Thing { }Bpublic class Thing { public Thing() {} }Cpublic class Thing { public Thing(void) {} }Dpublic class Thing { public Thing(String s) {} }Epublic class Thing { public void Thing() {} public Thing(String s) {} }

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.

单选题现有:  class Guy  {  String greet()  {  return "hi";  } } class Cowboy extends Guy  {  String greet()  {  return. "howdy";}}  class  Wrangler  extends  Cowboy  {  String  greet()  {  return  "orch!"; } }  class Greetings2  {  public  static void main (String  []  args)  {  Guy g=new Wrangler();  Guy g2=new Cowboy();  Wrangler w2=new Wrangler();  System. out .print (g.greet()+g2.greet()+w2 .greet());  }  }  结果是什么?()A hi hi ouch!B ouch!  howdy  ouch!C hi howdy ouch!D编译失败E运行的咐候有异常抛出

单选题Given the uncompleted code of a class:     class Person {  String name, department;     int age;  public Person(String n){  name = n; }  public Person(String n, int a){  name = n;  age = a;  }  public Person(String n, String d, int a) {  // doing the same as two arguments version of constructor     // including assignment name=n,age=a    department = d;     }     }  Which expression can be added at the "doing the same as..." part of the constructor?()A Person(n,a);B this(Person(n,a));C this(n,a);D this(name,age);

单选题现有:  class Guy {String greet()    {return "hi";  }  }  class Cowboy extends Guy  (  String greet()    (  return "howdy  ¨;    )  )  class Surfer extends Guy  (String greet()    (return "dude! ";)) class Greetings  {  public static void main (String  []  args)    {  Guy  []  guys =  ( new Guy(), new Cowboy(), new Surfer()  );  for (Guy g:  guys) System.out.print (g.greet()};  }  }  结果为:()A hi howdy dude!B运行时异常被抛出。C第7行出现一个错误,编译失败。D第8行出现一个错误,编译失败。

单选题class Guy { String greet() { return "hi "; } }  class Cowboy extends Guy { String greet() { return "howdy "; } }  class Wrangler extends Cowboy { String greet() { return "ouch! "; } }  class Greetings2 {  public static void main(String [] args) {  Guy g = new Wrangler();  Guy g2 = new Cowboy();  Wrangler w2 = new Wrangler();  System.out.print(g.greet()+g2.greet()+w2.greet());  }  }  结果是什么?()Ahi hi ouch!Bhi howdy ouch!Couch! howdy ouch!D编译失败

多选题public class Car {  private int wheelCount;  private String vin;  public Car(String vin) {  this.vin = vin;  this.wheelCount = 4;  }  public String drive() {  return “zoom-zoom”;  }  public String getInfo() {  return “VIN: “+ vin + “wheels: “+ wheelCount;  }  }  And:  public class MeGo extends Car {  public MeGo(String vin) {  this.wheelCount = 3;  }  }  What two must the programmer do to correct the compilation errors?()Ainsert a call to this() in the Car constructorBinsert a call to this() in the MeGo constructorCinsert a call to super() in the MeGo constructorDinsert a call to super(vin) in the MeGo constructorEchange the wheelCount variable in Car to protectedFchange line 3 in the MeGo class to super.wheelCount = 3;