判断题String s = (Double.valueOf("3.1415926")).toString()。A 对B 错

题目
判断题
String s = (Double.valueOf("3.1415926")).toString()。
A

B


相似考题

1.阅读下列Java程序和程序说明,将应填入(n)处的字句写在对应栏内。【说明】下面的程序先构造Point类,再顺序构造Ball类。由于在类Ball中不能直接存取类Point中的xCoordinate及yCoordinate属性值,Ball中的toString方法调用Point类中的toString方法输出中心点的值。在MovingBall类的toString方法中,super.toString调用父类Ball的toString方法输出类Ball中声明的属性值。public class Point{private double xCoordinate;private double yCoordinate;public Point 0 }public Point(ouble x, double y){xCoordinate = x;yCoordinate = y;}public String toString(){return "( + Double.toString(Coordinate)+ ","+ Double.toString(Coordinate) + ");}//other methods}public class Ball{(1); //中心点private double radius; //半径private String colour; ///颜色public Ball() { }public Ball(double xValue, double yValue, double r)// 具有中心点及半径的构造方法{center=(2);//调用类Point 中的构造方法radius = r;}public Ball(double xValue, double yValue, double r, String c)// 具有中心点、半径及颜色的构造方法{(3);//调用3个参数的构造方法colour = c;}public String toString(){return "A ball with center" + center, toString() + ", radius"+ Double.toString(radius) + ", colour" + colour;}//other methods}public class MovingBall. (4){private double speed;public MovingBall() { }public MovingBall(double xValue, double yValue, double r, String e, double s){(5);// 调用父类Ball中具有4个参数的构造方法speed = s;}public String toString( ){ return super, toString( ) + ", speed "+ Double.toString(speed); }//other methods}public class Tester{public static void main(String args[]){MovingBall mb = new MovingBall(10,20,40,"green",25);System.out.println(mb);}}

3.阅读以下函数说明和Java代码,将应填入(n)处的字句写在对应栏内。【说明】下面的程序先构造Point类,再顺序构造Ball类。由于在类Ball中不能直接存取类Point中的xCoordinate及yCoordinate属性值,Ball中的toString方法调用Point类中的toStrinS方法输出中心点的值。在MovingBsll类的toString方法中,super.toString调用父类Ball的toString方法输出类Ball中声明的属性值。【Java代码】//Point.java文件public class Point{private double xCoordinate;private double yCoordinate;public Point(){}public Point(double x,double y){xCoordinate=x;yCoordinate=y;}public String toStrthg(){return"("+Double.toString(xCoordinate)+","+Double.toString(yCoordinate)+")";}//other methods}//Ball.java文件public class Ball{private (1);//中心点private double radius;//半径private String color;//颜色public Ball(){}public Ball(double xValue, double yValue, double r){//具有中心点及其半径的构造方法center=(2);//调用类Point中的构造方法radius=r;}public Ball(double xValue, double yValue, double r, String c){//具有中心点、半径和颜色的构造方法(3);//调用3个参数的构造方法color=c;}public String toString(){return "A ball with center"+center.toString()+",radius "+Double.toString(radius)+",color"+color;}//other methods}class MovingBall (4) {private double speed;public MovingBall(){}public MoyingBall(double xValue, double yValue, double r, String c, double s){(5);//调用父类Ball中具有4个参数的构造方法speed=s;}public String toString(){return super.toString()+",speed"+Double.toString(speed);}//other methods}public class test{public static void main(String args[]){MovingBall mb=new MovingBall(10,20,40,"green",25);System.out.println(mb);}}

更多“String s = (Double.valueOf("3.1415926")).toString()。”相关问题
  • 第1题:

    下列的哪个程序段可能导致错误? ( )

    A.String s="hello"; String t="good"; String k=s+t;

    B.String s="hello"; String t; t=s[3]+"one";

    C.String s="hello"; String standard=s.toUpperCase();

    D.String s="hello"; String t=s+"good";


    正确答案:B

  • 第2题:

    当执行下列宏定义命令后,S的值为 ( ) # defineR3.0 # define PI 3.1415926 # define L2 * PI * R # define S PI * R * R

    A.3.1415926

    B.18.849556

    C.3

    D.28.2743334


    正确答案:D

  • 第3题:

    以下语句能顺利通过编译: class test { static void sayHello() { this.toString(); } public String toString() { retur。()

    此题为判断题(对,错)。


    答案:错


  • 第4题:

    下面的哪些程序片断可能导致错误() 

    • A、String s = "Gone with the wind";  String t = " good ";  String k = s + t;
    • B、String s = "Gone with the wind";  String t;  t = s[3] + "one";
    • C、String s = "Gone with the wind";  String standard = s.toUpperCase();
    • D、String s = "home directory"; String t = s - "directory"

    正确答案:B,D

  • 第5题:

    class A {   public String toString () {   return “4”;   }   }   class B extends A {   8. public String toString () {   return super.toString() + “3”;   }   }   public class Test {   public static void main(Stringargs) {   System.out.printIn(new B());   }   }   What is the result?()  

    • A、 Compilation succeeds and 4 is printed.
    • B、 Compilation succeeds and 43 is printed.
    • C、 An error on line 9 causes compilation to fail.
    • D、 An error on line 14 causes compilation to fail.
    • E、 Compilation succeeds but an exception is thrown at line 9.

    正确答案:B

  • 第6题:

    将逻辑值赋值给内存变量STRING1的正确方法是()

    • A、STRING1=IRUE
    • B、STORE”T”TOSTRING1
    • C、STORETTOSTRING1
    • D、STRING1=”T”

    正确答案:C

  • 第7题:

    关于国际化,下面那句话是错误的是()

    • A、不要使用String类的compareTo(),equals()方法。
    • B、在进行字符串连接时,不要使用String,使用StringBuffer。
    • C、不要使用Date.toString(),Time.toString()方法。
    • D、字符和字符串常量应该放在资源文件中。

    正确答案:B

  • 第8题:

    Given:  310-025   Leading the way in IT testing and certification tools, www.testking.com   - 48 -   public class foo {   static String s;   public static void main (Stringargs) {   system.out.printIn (“s=” + s);   }   }   What is the result?()

    • A、 The code compiles and “s=” is printed.
    • B、 The code compiles and “s=null” is printed.
    • C、 The code does not compile because string s is not initialized.
    • D、 The code does not compile because string s cannot be referenced.
    • E、 The code compiles, but a NullPointerException is thrown when toString is called.

    正确答案:B

  • 第9题:

    Which of the following fragments might cause errors?()    

    • A、 String s = "Gone with the wind";String t = " good ";String k = s + t;
    • B、 String s = "Gone with the wind";String t;t = s[3] + "one";
    • C、 String s = "Gone with the wind";String standard = s.toUpperCase();
    • D、 String s = "home directory";String t = s - "directory";

    正确答案:B,D

  • 第10题:

    单选题
    public String makinStrings() {  String s = “Fred”;  s = s + “47”;  s = s.substring(2, 5);  s = s.toUpperCase();  return s.toString();  }  How many String objects will be created when this method is invoked?()
    A

     1

    B

     2

    C

     3

    D

     4

    E

     5

    F

     6


    正确答案: E
    解析: 暂无解析

  • 第11题:

    单选题
    class A {   public String toString () {   return “4”;   }   }   class B extends A {   8. public String toString () {   return super.toString() + “3”;   }   }   public class Test {   public static void main(Stringargs) {   System.out.printIn(new B());   }   }   What is the result?()
    A

     Compilation succeeds and 4 is printed.

    B

     Compilation succeeds and 43 is printed.

    C

     An error on line 9 causes compilation to fail.

    D

     An error on line 14 causes compilation to fail.

    E

     Compilation succeeds but an exception is thrown at line 9.


    正确答案: C
    解析: 暂无解析

  • 第12题:

    单选题
    public class foo {   public static void main (Stringargs) {  String s;   system.out.printIn (“s=” + s);   }   }   What is the result?()
    A

     The code compiles and “s=” is printed.

    B

     The code compiles and “s=null” is printed.

    C

     The code does not compile because string s is not initialized.

    D

     The code does not compile because string s cannot be referenced.

    E

     The code compiles, but a NullPointerException is thrown when toString is called.


    正确答案: E
    解析: 暂无解析

  • 第13题:

    下面这段代码会产生( )个String对象。

    Strings1="hello";

    Strings2=s1.substring(2,3);

    Strings3=s1.toString();

    Strings4=newStringBuffer(s1).toString();

    A、1

    B、2

    C、3

    D、4


    正确答案:C

  • 第14题:

    以下程序能顺利通过编译: public class am_I_right { public static void main(String args[]) { this.toString(); } String toString() { retur。()

    此题为判断题(对,错)。


    答案:错

  • 第15题:

    以下程序能顺利通过编译: class student { String sno,sname; static void output() { this.toString(); } String toString() { retur。()

    此题为判断题(对,错)。


    答案:错


  • 第16题:

    public class foo {   public static void main (Stringargs) {  String s;   system.out.printIn (“s=” + s);   }   }   What is the result?()

    • A、 The code compiles and “s=” is printed.
    • B、 The code compiles and “s=null” is printed.
    • C、 The code does not compile because string s is not initialized.
    • D、 The code does not compile because string s cannot be referenced.
    • E、 The code compiles, but a NullPointerException is thrown when toString is called.

    正确答案:C

  • 第17题:

    public String makinStrings() {  String s = “Fred”;  s = s + “47”;  s = s.substring(2, 5);  s = s.toUpperCase();  return s.toString();  }  How many String objects will be created when this method is invoked?() 

    • A、 1
    • B、 2
    • C、 3
    • D、 4
    • E、 5
    • F、 6

    正确答案:C

  • 第18题:

    下面哪个不是String类的方法?()

    • A、subString()
    • B、startsWith()
    • C、toString()
    • D、toUpperCase()

    正确答案:C

  • 第19题:

    String s = (Double.valueOf("3.1415926")).toString()。


    正确答案:正确

  • 第20题:

    public class foo {  public static void main (String[]args) {  String s;  system.out.printIn (“s=” + s);  }  }   What is the result?()  

    • A、 The code compiles and “s=” is printed.
    • B、 The code compiles and “s=null” is printed.
    • C、 The code does not compile because string s is not initialized.
    • D、 The code does not compile because string s cannot be referenced.
    • E、 The code compiles, but a NullPointerException is thrown when toString is called.

    正确答案:C

  • 第21题:

    1. interface TestA { String toString(); }  2. public class Test {  3. public static void main(String[] args) {  4. System.out.println(new TestA() {  5. public String toString() { return “test”; }  6. }  7. }  8. }  What is the result?() 

    • A、 test
    • B、 null
    • C、 An exception is thrown at runtime.
    • D、 Compilation fails because of an error in line 1.
    • E、 Compilation fails because of an error in line 4.
    • F、 Compilation fails because of an error in line 5.

    正确答案:A

  • 第22题:

    单选题
    Given:  310-025   Leading the way in IT testing and certification tools, www.testking.com   - 48 -   public class foo {   static String s;   public static void main (Stringargs) {   system.out.printIn (“s=” + s);   }   }   What is the result?()
    A

     The code compiles and “s=” is printed.

    B

     The code compiles and “s=null” is printed.

    C

     The code does not compile because string s is not initialized.

    D

     The code does not compile because string s cannot be referenced.

    E

     The code compiles, but a NullPointerException is thrown when toString is called.


    正确答案: B
    解析: 暂无解析

  • 第23题:

    单选题
    public class foo {  public static void main (String[]args) {  String s;  system.out.printIn (“s=” + s);  }  }   What is the result?()
    A

     The code compiles and “s=” is printed.

    B

     The code compiles and “s=null” is printed.

    C

     The code does not compile because string s is not initialized.

    D

     The code does not compile because string s cannot be referenced.

    E

     The code compiles, but a NullPointerException is thrown when toString is called.


    正确答案: A
    解析: 暂无解析