java程序设计教程(第六版)课后习题答案

pp2.3public class fudian {public static void main(String[] args) {float a=2.10f,b=3.70f;float Result1,Result2,Result3;Result1=a+b;Result2=a-b;Result3=a*b;System.out.println("Result1 is:"+Result1);System.out.println("Result2 is:"+Result2);System.out.println("Result3 is:"+Result3);}}2.4public class TempConverter {public static void main(String[] args) {final int BASE = 32;final double CONVERSION_FACTOR = 5.0 / 9.0;double celsiusTemp;int fahrenheitTemp = 70; // value to convertcelsiusTemp = (fahrenheitTemp - BASE)*CONVERSION_FACTOR;System.out.println ("Fahrenheit Equivalent: " + fahrenheitTemp);System.out.println ("Celsius Temperature: " + celsiusTemp);}}2.5public class yinglizhuanqianmi {public static void main(String[] args) {float Base=1.60935f;float Qianmi;float Yingli=19.85f;Qianmi=Yingli*Base;System.out.println ("Ying Li: " + Yingli);System.out.println ("Qian Mi: " +Qianmi);}}2.6public class TimeConverter1 {public static void main(String[] args) {int Hour=5,Minute=35,Second=51;int SECONDS;SECONDS=Hour*60*60+Minute*60+Second;System.out.println (+Hour+"时"+Minute+"分"+Second+"秒");System.out.println ("换算成秒: " + SECONDS);}}2.7public class TimeConverter2 {public static void main(String[] args) {int SECONDS=10853;int Hour,Minute,Second;Second=SECONDS%60;Minute=(SECONDS-Second)%60;Hour=(SECONDS-Second-Minute*60)/3600;System.out.println (SECONDS+"秒，转化为");System.out.println (Hour+"时"+Minute+"分"+Second+"秒");}}2.9import java.util.*;public class Dollarbill {public static void main(String[] args) {float Dollar1,Dollar2;int Ten,Five,One,Quarters,Dimes,Nickles,Pennies;Scanner reader=new Scanner(System.in);System.out.println("输入币值：");Dollar1=reader.nextFloat();Dollar2=Dollar1*100;Pennies= (int)Dollar2%5;Nickles=((int)Dollar2%10-Pennies)/5;Dimes=((int)Dollar2-Pennies-Nickles*5)%50/10;Quarters=(int)Dollar2%100/50;One=((int)Dollar2- Pennies-Nickles*5-Dimes*10-Quarters*50)%500/100;Five=(int)Dollar2%1000/500;Ten=(int)Dollar2/1000;System.out.println(Ten+ "ten dollar bills");System.out.println(Five+ " five dollar bills");System.out.println(One+ "one dollar bills");System.out.println(Quarters+ "quarters dollar bills");System.out.println(Dimes+ "dimes dollar bills");System.out.println(Nickles+ "nickles dollar bills");System.out.println(Pennies+ "pennies dollar bills！");}}2.11import java.util.*;public class Fenshuzhuanhuan {public static void main(String[] args) {int x,y;double Result=0;Scanner reader=new Scanner(System.in);System.out.println("输入x：");x=reader.nextInt();System.out.println("输入y：");y=reader.nextInt();Result+=x/y;System.out.println ("分数"+x+"/"+y);System.out.println ("转换成小数是: " + Result);}}2.16import javax.swing.JApplet;import java.awt.*;public class Olympiclogo extends JApplet{public void paint (Graphics page) {page.setColor(Color.blue);page.drawOval(25, 65, 40, 40);page.setColor(Color.yellow);page.drawOval (55, 65, 40, 40);page.setColor(Color.black);page.drawOval (85, 65, 40, 40);page.setColor(Color.green);page.drawOval (115, 65, 40, 40);page.setColor(Color.red);page.drawOval (145, 65, 40, 40);// circlepage.setColor(Color.cyan);page.drawString ("OL YMPIC LOGO", 40, 30);}}2.19import java.applet.*;import java.awt.*;public class Ex2_19 extends Applet{public void paint (Graphics page){page.setColor(Color.BLACK);page.setFont(new Font("楷体",Font.ITALIC+Font.BOLD,30));page.drawString ("林少锋", 40, 30);page.setColor(Color.blue);page.setFont(new Font("宋体",Font.BOLD,30));page.drawString ("林少锋", 70, 80);}}2.20import java.applet.*;import java.awt.*;public class Ex2_20 extends Applet{public void paint (Graphics page){page.drawOval(35, 35, 130, 130);page.setColor(Color.red);page.fillArc(35, 35, 130, 130,0,45);page.setColor(Color.blue);page.fillArc(35, 35, 130, 130,45,45);page.setColor(Color.yellow);page.fillArc(35, 35, 130, 130,90,45);page.setColor(Color.cyan);page.fillArc(35, 35, 130, 130,135,45);page.setColor(Color.gray);page.fillArc(35, 35, 130, 130,180,45);page.setColor(Color.green);page.fillArc(35, 35, 130, 130,225,45);page.setColor(Color.darkGray);page.fillArc(35, 35, 130, 130,270,45);page.setColor(Color.pink);page.fillArc(35, 35, 130, 130,315,45);}}PP4.1方法1import java.util.*;public class CreateSphere {/*** @param args*/public static void main(String[] args) {// TODO 自动生成方法存根System.out.println("请输入直径d：");Scanner scan=new Scanner(System.in);double d=scan.nextDouble();Sphere D=new Sphere(d);D.Square();D.Volum();System.out.println(D.toString());}}public class Sphere {final double PI=3.14;double V,S;double d;Sphere(double d){this.d=d;}public void V olum(){V=(4/3)*PI*(d/2)*(d/2)*(d/2);}public void Square(){S=4*PI*(d/2)*(d/2);}public String toString(){String s="";String result1=Double.toString(S);String result2=Double.toString(V);s=("体积为："+result2+"面积为："+result1);return s;}}方法2//Sphere.javapublic class Sphere{private double diameter;public Sphere(){//构造方法：无参数this.diameter = 1.0;}public Sphere(double d){ //构造方法：带一个参数this.diameter = d;}public void setDiameter(double d) {//设置直径值的方法this.diameter = d;}public double getDiameter(){//获取直径值的方法return this.diameter;}public double volume(){//计算球的体积return 4*Math.PI*Math.pow(this.diameter/2,3)/3;}public double area(){//计算球的表面积return 4*Math.PI*Math.pow(this.diameter/2,2);}public String toString(){String out = "该球体的直径为：" + this.diameter + "\n" + "该球体的表面积为：" + this.area() + "\n" +"该球体的体积为：" + this. volume();return out;}}//MultiSphere.javaimport java.util.Scanner;public class MultiSphere{public static void main(String[] args){Scanner scan = new Scanner(System.in);Sphere sphere1 = new Sphere();Sphere sphere2 = new Sphere(3.5);System.out.println("sphere1: " + sphere1 + "\n");System.out.println("sphere2: " + sphere2 + "\n");System.out.println("sphere1和sphere2分别调用无参构造方法" +"和带一个参数的构造方法进行初始化。