Java 2实用大学教程实验指导与习题解答(10)

{ String success=\

for(int k=0;k

if(success.equals(word))

{ messaageLabel.setText(\恭喜你，你成功了\ for(int k=0;k

{ label[k].removeKeyListener(this); label[k].removeFocusListener(label[k]);

label[k].setBackground(Color.green); }

inputWord.requestFocus(); } } }

WordMainClass.java

public class WordMainClass

{ public static void main(String args[]) { new SpellingWordFrame(); } }

上机实践8 多线程

实验1 汉字打字练习

1．答案：

【代码1】： sleep(6000);

【代码2】： WordThread giveWord;

【代码3】： giveWord=new WordThread(wordLabel); 【代码4】： giveWord.isAlive() 【代码5】： giveWord.start();

2．模板代码 WordThread.java

import java.awt.*;

public class WordThread extends Thread { char word; int k=19968;

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Label com;

WordThread(Label com) { this.com=com; }

public void run() { k=19968; while(true) {

word=(char)k; com.setText(\

try{ 【代码1】//调用sleep方法使得线程中断6000豪秒 }

catch(InterruptedException e){} k++;

if(k>=29968) k=19968; } } }

ThreadFrame.java

import java.awt.*; import java.awt.event.*;

public class ThreadFrame extends Frame implements ActionListener {

Label wordLabel; Button button;

TextField inputText,scoreText;

【代码2】//用WordThread声明一个giveWord对象 int score=0; ThreadFrame()

{ wordLabel=new Label(\ wordLabel.setFont(new Font(\ button=new Button(\开始\ inputText=new TextField(3); scoreText=new TextField(5); scoreText.setEditable(false);

【代码3】//创建giveWord，将wordLabel传递给WordThread构造方法的参数 button.addActionListener(this); inputText.addActionListener(this); add(button,BorderLayout.NORTH); add(wordLabel,BorderLayout.CENTER); Panel southP=new Panel();

southP.add(new Label(\输入标签所显示的汉字后回车:\ southP.add(inputText); southP.add(scoreText);

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add(southP,BorderLayout.SOUTH); setBounds(100,100,350,180); setVisible(true); validate();

addWindowListener(new WindowAdapter()

{ public void windowClosing(WindowEvent e) { System.exit(0); } } ); }

public void actionPerformed(ActionEvent e) {

if(e.getSource()==button)

{ if(!(【代码4】)) //giveWord调用方法isAlive() { giveWord=new WordThread(wordLabel); } try

{ 【代码5】//giveWord调用方法start() }

catch(Exception exe){} }

else if(e.getSource()==inputText)

{ if(inputText.getText().equals(wordLabel.getText())) { score++; }

scoreText.setText(\得分:\ inputText.setText(null); } } }

WordThread.java

public class ThreadWordMainClass

{ public static void main(String args[]) { new ThreadFrame(); }

实验2 旋转的行星

1．答案：

【代码1】： Thread moon;

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【代码2】： thread=new Thread(this); 【代码3】： Thread.sleep(10); 【代码4】： Thread rotate; 【代码5】： rotate.start();

2．模板代码 Mycanvas.java

import java.awt.*;

public class Mycanvas extends Canvas { int r; Color c;

public void setColor(Color c) { this.c=c; }

public void setR(int r) { this.r=r; }

public void paint(Graphics g) { g.setColor(c);

g.fillOval(0,0,2*r,2*r); }

public int getR() { return r; } }

Planet.java

import java.awt.*;

public class Planet extends Panel implements Runnable { 【代码1】 //用Thread类声明一个moon对象 Mycanvas yellowBall;

double pointX[]=new double[360],

pointY[]=new double[360]; //用来表示画布左上角端点坐标的数组 int w=100,h=100; int radius=30; Planet()

{ setSize(w,h); setLayout(null);

yellowBall=new Mycanvas();

yellowBall.setColor(Color.yellow); add(yellowBall);

yellowBall.setSize(12,12); yellowBall.setR(12/2); pointX[0]=0;

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pointY[0]=-radius;

double angle=1*Math.PI/180; //刻度为1度

for(int i=0;i<359;i++) //计算出数组中各个元素的值

{ pointX[i+1]=pointX[i]*Math.cos(angle)-Math.sin(angle)*pointY[i]; pointY[i+1]=pointY[i]*Math.cos(angle)+pointX[i]*Math.sin(angle); }

for(int i=0;i<360;i++)

{ pointX[i]=pointX[i]+w/2; //坐标平移 pointY[i]=pointY[i]+h/2; }

yellowBall.setLocation((int)pointX[0]-yellowBall.getR(),

(int)pointY[0]-yellowBall.getR());

【代码2】 //创建 moon线程，当前面板做为该线程的目标对象 }

public void start() { try{ moon .start(); }

catch(Exception exe){} }

public void paint(Graphics g) { g.setColor(Color.blue); g.fillOval(w/2-9,h/2-9,18,18); }

public void run() { int i=0; while(true) { i=(i+1)60;

yellowBall.setLocation((int)pointX[i]-yellowBall.getR(),

(int)pointY[i]-yellowBall.getR());

try{ 【代码3】 // Thread类调用类方法sleep使得线程中断10豪秒 }

catch(InterruptedException e){} } } }

HaveThreadFrame.java

import java.awt.*; import java.awt.event.*;

public class HaveThreadFrame extends Frame implements Runnable { 【代码4】 //用Thread类声明一个rotate对象 Planet earth;

double pointX[]=new double[360], pointY[]=new double[360]; int width,height;

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