java程序设计教程(第六版)课后习题答案(3)

import 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);

}

}

2.16

import 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);// circle

page.setColor(Color.cyan);

page.drawString ("OLYMPIC LOGO", 40, 30);

}

}

2.19

import 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));