1、實驗目的與要求

(1) 掌握執行緒概念；

(2) 掌握執行緒建立的兩種技術；

(3) 理解和掌握執行緒的優先順序屬性及排程方法；

(4) 掌握執行緒同步的概念及實現技術；

2、實驗內容和步驟

實驗1：測試程式並進行程式碼註釋。

測試程式1：

l 在elipse IDE中除錯執行ThreadTest，結合程式執行結果理解程式；

l 掌握執行緒概念；

l 掌握用Thread的擴充套件類實現執行緒的方法；

利用Runnable介面改造程式，掌握用Runnable介面建立執行緒的方法。

class Lefthand extends
 
 Thread { 
   public void run()
   {
       for(int i=0;i<=5;i++)
       {  System.out.println("You are Students!");
           try{   sleep(500);   }
           catch(InterruptedException e)
           { System.out.println("Lefthand error.");}    
       } 
  } 
}
class Righthand extends Thread {
    
 
public void run()
    {
         for(int i=0;i<=5;i++)
         {   System.out.println("I am a Teacher!");
             try{  sleep(300);  }
             catch(InterruptedException e)
             { System.out.println("Righthand error.");}
         }
    }
}
public class ThreadTest 
{
     static Lefthand left;
     
 
static Righthand right;
     public static void main(String[] args)
     {     left=new Lefthand();
           right=new Righthand();
           left.start();
           right.start();
     }
}

ThreadTest

利用Runnable介面改造程式，掌握用Runnable介面建立執行緒的方法

class Lefthand implements Runnable { 
   public void run()
   {
       for(int i=0;i<=5;i++)
       {  System.out.println("You are Students!");
           try{   Thread.sleep(500);//休眠500毫秒
           }
           catch(InterruptedException e)
           { System.out.println("Lefthand error.");}    
       } 
  }
   
 }
class Righthand implements Runnable {
    public void run()
    {
         for(int i=0;i<=5;i++)
         {   System.out.println("I am a Teacher!");
             try{  Thread.sleep(300);//休眠300毫秒
             }
             catch(InterruptedException e)
             { System.out.println("Righthand error.");}
         }
    }
   
 }
public class ThreadTest 
{
     public static void main(String[] args)
     {   

       Righthand righthand = new Righthand();//新建一個righthand物件
        Lefthand lefthand = new Lefthand();//新建一個lefthand物件
         Thread right = new Thread(righthand);//start方法在Thread類中，新建Thread類
         right.start();
           Thread left=new Thread(lefthand);
          left.start();
     }
}

Runnable介面

測試程式2：

l 在Elipse環境下除錯教材625頁程式14-1、14-2 、14-3，結合程式執行結果理解程式；

l 在Elipse環境下除錯教材631頁程式14-4，結合程式執行結果理解程式；

l 對比兩個程式，理解執行緒的概念和用途；

l 掌握執行緒建立的兩種技術。

package bounce;

import java.awt.geom.*;

/**
 * A ball that moves and bounces off the edges of a rectangle
 * @version 1.33 2007-05-17
 * @author Cay Horstmann
 */
public class Ball
{
   private static final int XSIZE = 15;
   private static final int YSIZE = 15;
   private double x = 0;
   private double y = 0;
   private double dx = 1;
   private double dy = 1;

   /**
    * Moves the ball to the next position, reversing direction if it hits one of the edges
    */
   public void move(Rectangle2D bounds)
   {
      x += dx;
      y += dy;
      if (x < bounds.getMinX())
      {
         x = bounds.getMinX();
         dx = -dx;
      }
      if (x + XSIZE >= bounds.getMaxX())
      {
         x = bounds.getMaxX() - XSIZE;
         dx = -dx;
      }
      if (y < bounds.getMinY())
      {
         y = bounds.getMinY();
         dy = -dy;
      }
      if (y + YSIZE >= bounds.getMaxY())
      {
         y = bounds.getMaxY() - YSIZE;
         dy = -dy;
      }
   }

   /**
    * Gets the shape of the ball at its current position.
    */
   public Ellipse2D getShape()
   {
      return new Ellipse2D.Double(x, y, XSIZE, YSIZE);
   }
}

ball

package bounce;

import java.awt.*;
import java.util.*;
import javax.swing.*;

/**
 * The component that draws the balls.
 * @version 1.34 2012-01-26
 * @author Cay Horstmann
 */
public class BallComponent extends JPanel
{
   private static final int DEFAULT_WIDTH = 450;
   private static final int DEFAULT_HEIGHT = 350;

   private java.util.List<Ball> balls = new ArrayList<>();

   /**
    * Add a ball to the component.
    * @param b the ball to add
    */
   public void add(Ball b)
   {
      balls.add(b);
   }

   public void paintComponent(Graphics g)
   {
      super.paintComponent(g); // erase background
      Graphics2D g2 = (Graphics2D) g;
      for (Ball b : balls)
      {
         g2.fill(b.getShape());
      }
   }
   
   public Dimension getPreferredSize() { return new Dimension(DEFAULT_WIDTH, DEFAULT_HEIGHT); }
}

BallComponent

package bounce;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/**
 * Shows an animated bouncing ball.
 * @version 1.34 2015-06-21
 * @author Cay Horstmann
 */
public class Bounce
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         JFrame frame = new BounceFrame();
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

/**
 * The frame with ball component and buttons.
 */
class BounceFrame extends JFrame
{
   private BallComponent comp;
   public static final int STEPS = 1000;
   public static final int DELAY = 3;

   /**
    * Constructs the frame with the component for showing the bouncing ball and
    * Start and Close buttons
    */
   public BounceFrame()
   {
      setTitle("Bounce");
      comp = new BallComponent();
      add(comp, BorderLayout.CENTER);
      JPanel buttonPanel = new JPanel();
      addButton(buttonPanel, "Start", event -> addBall());
      addButton(buttonPanel, "Close", event -> System.exit(0));
      add(buttonPanel, BorderLayout.SOUTH);
      pack();
   }

   /**
    * Adds a button to a container.
    * @param c the container
    * @param title the button title
    * @param listener the action listener for the button
    */
   public void addButton(Container c, String title, ActionListener listener)
   {
      JButton button = new JButton(title);
      c.add(button);
      button.addActionListener(listener);
   }

   /**
    * Adds a bouncing ball to the panel and makes it bounce 1,000 times.
    */
   public void addBall()
   {
      try
      {
         Ball ball = new Ball();
         comp.add(ball);

         for (int i = 1; i <= STEPS; i++)
         {
            ball.move(comp.getBounds());
            comp.paint(comp.getGraphics());
            Thread.sleep(DELAY);
         }
      }
      catch (InterruptedException e)
      {
      }
   }
}

Bounce

package bounceThread;

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

import javax.swing.*;

/**
 * Shows animated bouncing balls.
 * @version 1.34 2015-06-21
 * @author Cay Horstmann
 */
public class BounceThread
{
   public static void main(String[] args)
   {
      EventQueue.invokeLater(() -> {
         JFrame frame = new BounceFrame();
         frame.setTitle("BounceThread");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}

/**
 * The frame with panel and buttons.
 */
class BounceFrame extends JFrame
{
   private BallComponent comp;
   public static final int STEPS = 1000;
   public static final int DELAY = 5;


   /**
    * Constructs the frame with the component for showing the bouncing ball and
    * Start and Close buttons
    */
   public BounceFrame()
   {
      comp = new BallComponent();
      add(comp, BorderLayout.CENTER);
      JPanel buttonPanel = new JPanel();
      addButton(buttonPanel, "Start", event -> addBall());
      addButton(buttonPanel, "Close", event -> System.exit(0));
      add(buttonPanel, BorderLayout.SOUTH);
      pack();
   }

   /**
    * Adds a button to a container.
    * @param c the container
    * @param title the button title
    * @param listener the action listener for the button
    */
   public void addButton(Container c, String title, ActionListener listener)
   {
      JButton button = new JButton(title);
      c.add(button);
      button.addActionListener(listener);
   }

   /**
    * Adds a bouncing ball to the canvas and starts a thread to make it bounce
    */
   public void addBall()
   {
      Ball ball = new Ball();
      comp.add(ball);
      Runnable r = () -> { 
         try
         {  
            for (int i = 1; i <= STEPS; i++)
            {
               ball.move(comp.getBounds());
               comp.repaint();
               Thread.sleep(DELAY);
            }
         }
         catch (InterruptedException e)
         {
         }
      };
      Thread t = new Thread(r);
      t.start();
   }
}

BounceThread

測試程式3：分析以下程式執行結果並理解程式。

 

class Race extends Thread {
  public static void main(String args[]) {
    Race[] runner=new Race[4];
    for(int i=0;i<4;i++) runner[i]=new Race( );
   for(int i=0;i<4;i++) runner[i].start( );
   runner[1].setPriority(MIN_PRIORITY);
   runner[3].setPriority(MAX_PRIORITY);}
  public void run( ) {
      for(int i=0; i<1000000; i++);
      System.out.println(getName()+"執行緒的優先順序是"+getPriority()+"已計算完畢!");
    }
}

Race extends Thread

測試程式4

l 教材642頁程式模擬一個有若干賬戶的銀行，隨機地生成在這些賬戶之間轉移錢款的交易。每一個賬戶有一個執行緒。在每一筆交易中，會從執行緒所服務的賬戶中隨機轉移一定數目的錢款到另一個隨機賬戶。

l 在Elipse環境下除錯教材642頁程式14-5、14-6，結合程式執行結果理解程式；

package unsynch;

/**
 * This program shows data corruption when multiple threads access a data structure.
 * @version 1.31 2015-06-21
 * @author Cay Horstmann
 */
public class UnsynchBankTest
{
   public static final int NACCOUNTS = 100;
   public static final double INITIAL_BALANCE = 1000;//期初餘額
   public static final double MAX_AMOUNT = 1000;//最大數量
   public static final int DELAY = 10;//延時
   
   public static void main(String[] args)
   {
      Bank bank = new Bank(NACCOUNTS, INITIAL_BALANCE);
      for (int i = 0; i < NACCOUNTS; i++)
      {
         int fromAccount = i;
         Runnable r = () -> {
            try
            {
               while (true)
               {
                  int toAccount = (int) (bank.size() * Math.random());//生成隨機數
                  double amount = MAX_AMOUNT * Math.random();
                  bank.transfer(fromAccount, toAccount, amount);
                  Thread.sleep((int) (DELAY * Math.random()));
               }
            }
            catch (InterruptedException e)
            {
            }            
         };
         Thread t = new Thread(r);
         t.start();
      }
   }
}

UnsynchBankTest

package unsynch;

import java.util.*;

/**
 * A bank with a number of bank accounts.
 * @version 1.30 2004-08-01
 * @author Cay Horstmann
 */
public class Bank
{
   private final double[] accounts;

   /**
    * Constructs the bank.
    * @param n the number of accounts
    * @param initialBalance the initial balance for each account
    */
   public Bank(int n, double initialBalance)
   {
      accounts = new double[n];
      Arrays.fill(accounts, initialBalance);
   }

   /**
    * Transfers money from one account to another.
    * @param from the account to transfer from
    * @param to the account to transfer to
    * @param amount the amount to transfer
    */
   public void transfer(int from, int to, double amount)
   {
      if (accounts[from] < amount) return;
      System.out.print(Thread.currentThread());
      accounts[from] -= amount;
      System.out.printf(" %10.2f from %d to %d", amount, from, to);
      accounts[to] += amount;
      System.out.printf(" Total Balance: %10.2f%n", getTotalBalance());
   }

   /**
    * Gets the sum of all account balances.
    * @return the total balance
    */
   public double getTotalBalance()
   {
      double sum = 0;

      for (double a : accounts)
         sum += a;

      return sum;
   }

   /**
    * Gets the number of accounts in the bank.
    * @return the number of accounts
    */
   public int size()
   {
      return accounts.length;
   }
}

Bank

綜合程式設計練習

程式設計練習1

1. 設計一個使用者資訊採集程式，要求如下：

使用者資訊輸入介面如下圖所示:

（1） 使用者點選提交按鈕時，使用者輸入資訊顯示控制檯介面；

（2） 使用者點選重置按鈕後，清空使用者已輸入資訊；

（3） 點選視窗關閉，程式退出。

import java.awt.EventQueue;

import javax.swing.JFrame;

public class Mian {
    public static void main(String[] args) {
        EventQueue.invokeLater(() -> {
            DemoJFrame page = new DemoJFrame();
        });
    }
}

Mian

import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.LayoutManager;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Timer;
import java.util.TimerTask;

import javax.swing.BorderFactory;
import javax.swing.ButtonGroup;
import javax.swing.ButtonModel;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.JTextField;

public class DemoJFrame extends JFrame {
    private JPanel jPanel1;
    private JPanel jPanel2;
    private JPanel jPanel3;
    private JPanel jPanel4;
    private JTextField fieldname;
    private JComboBox comboBox;
    private JTextField fieldadress;
    private ButtonGroup bg;
    private JRadioButton nan;
    private JRadioButton nv;
    private JCheckBox sing;
    private JCheckBox dance;
    private JCheckBox draw;

    public DemoJFrame() {
        // 設定視窗大小
        this.setSize(800, 400);
        // 設定可見性
        this.setVisible(true);
        // 設定標題
        this.setTitle("Student Detail");
        // 設定關閉操作
        this.setDefaultCloseOperation(EXIT_ON_CLOSE);
        // 設定視窗居中
        WinCenter.center(this);
        // 建立四個面板物件
        jPanel1 = new JPanel();
        setJPanel1(jPanel1);
        jPanel2 = new JPanel();
        setJPanel2(jPanel2);
        jPanel3 = new JPanel();
        setJPanel3(jPanel3);
        jPanel4 = new JPanel();
        setJPanel4(jPanel4);
        // 設定容器為流式佈局
        FlowLayout flowLayout = new FlowLayout();
        this.setLayout(flowLayout);
        // 將四個面板新增到容器中
        this.add(jPanel1);
        this.add(jPanel2);
        this.add(jPanel3);
        this.add(jPanel4);

    }

    /*
     * 設定面板一
     */
    private void setJPanel1(JPanel jPanel) {
        jPanel.setPreferredSize(new Dimension(700, 45));//設定此元件的首選大小
        // 給面板的佈局設定為網格佈局 一行4列
        jPanel.setLayout(new GridLayout(1, 4));
        JLabel name = new JLabel("Name:");
        name.setSize(100, 50);
        fieldname = new JTextField("");
        fieldname.setSize(80, 20);
        JLabel study = new JLabel("Qualification:");
        comboBox = new JComboBox();
        comboBox.addItem("Graduate");
        comboBox.addItem("senior");
        comboBox.addItem("Undergraduate");
        jPanel.add(name);
        jPanel.add(fieldname);
        jPanel.add(study);
        jPanel.add(comboBox);

    }

    /*
     * 設定面板二
     */
    private void setJPanel2(JPanel jPanel) {
        jPanel.setPreferredSize(new Dimension(700, 50));
        // 給面板的佈局設定為網格佈局 一行4列
        jPanel.setLayout(new GridLayout(1, 4));
        JLabel name = new JLabel("Address:");
        fieldadress = new JTextField();
        fieldadress.setPreferredSize(new Dimension(150, 50));
        JLabel study = new JLabel("Hobby:");
        JPanel selectBox = new JPanel();
        selectBox.setBorder(BorderFactory.createTitledBorder(""));
        selectBox.setLayout(new GridLayout(3, 1));
        sing = new JCheckBox("Singing");
        dance = new JCheckBox("Dancing");
        draw = new JCheckBox("Reading");
        selectBox.add(sing);
        selectBox.add(dance);
        selectBox.add(draw);
        jPanel.add(name);
        jPanel.add(fieldadress);
        jPanel.add(study);
        jPanel.add(selectBox);
    }

    /*
     * 設定面板三
     */
    private void setJPanel3(JPanel jPanel) {
        jPanel.setPreferredSize(new Dimension(700, 150));
        FlowLayout flowLayout = new FlowLayout(FlowLayout.LEFT);
        jPanel.setLayout(flowLayout);
        JLabel sex = new JLabel("Sex:");
        JPanel selectBox = new JPanel();
        selectBox.setBorder(BorderFactory.createTitledBorder(""));
        selectBox.setLayout(new GridLayout(2, 1));
        bg = new ButtonGroup();
        nan = new JRadioButton("Male");
        nv = new JRadioButton("Female");
        bg.add(nan);
        bg.add(nv);
        selectBox.add(nan);
        selectBox.add(nv);
        jPanel.add(sex);
        jPanel.add(selectBox);

    }

    /*
     * 設定面板四
     */
    private void setJPanel4(JPanel jPanel) {
        // TODO 自動生成的方法存根
        jPanel.setPreferredSize(new Dimension(700, 150));
        FlowLayout flowLayout = new FlowLayout(FlowLayout.CENTER, 50, 10);
        jPanel.setLayout(flowLayout);
        jPanel.setLayout(flowLayout);
        JButton sublite = new JButton("Validate");
        JButton reset = new JButton("Reset");
        sublite.addActionListener((e) -> valiData());
        reset.addActionListener((e) -> Reset());
        jPanel.add(sublite);
        jPanel.add(reset);
    }

    /*
     * 提交資料
     */
    private void valiData() {
        // 拿到資料
        String name = fieldname.getText().toString().trim();
        String xueli = comboBox.getSelectedItem().toString().trim();
        String address = fieldadress.getText().toString().trim();
        System.out.println(name);
        System.out.println(xueli);
        String hobbystring="";
        if (sing.isSelected()) {
            hobbystring+="Singing   ";
        }
        if (dance.isSelected()) {
            hobbystring+="Dancing   ";
        }
        if (draw.isSelected()) {
            hobbystring+="Reading  ";
        }
        System.out.println(address);
        if (nan.isSelected()) {
            System.out.println("Male");
        }
        if (nv.isSelected()) {
            System.out.println("Female");
        }
        System.out.println(hobbystring);
    }

    /*
     * 重置
     */
    private void Reset() {
        fieldadress.setText(null);
        fieldname.setText(null);
        comboBox.setSelectedIndex(0);
        sing.setSelected(false);
        dance.setSelected(false);
        draw.setSelected(false);
        bg.clearSelection();
    }
}

DemoJFrame

import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.Window;

public class WinCenter {
    public static void center(Window win){
        Toolkit tkit = Toolkit.getDefaultToolkit();//獲取預設工具包
        Dimension sSize = tkit.getScreenSize();//獲取螢幕的大小
        Dimension wSize = win.getSize();
        if(wSize.height > sSize.height){
            wSize.height = sSize.height;
        }
        if(wSize.width > sSize.width){
            wSize.width = sSize.width;
        }
        win.setLocation((sSize.width - wSize.width)/ 2, (sSize.height - wSize.height)/ 2);//將元件移到新的位置
    }
}

WinCenter

2．建立兩個執行緒，每個執行緒按順序輸出5次“你好”，每個“你好”要標明來自哪個執行緒及其順序號。

package shiyan2;
 
public class xiancheng 
{

    static xian1 xian11;
    static xian2 xian22;        
   public static void main(String[] args)
   {    xian11=new xian1();
       xian22=new xian2();               //用start（）方法啟動執行緒
       xian11.start();
       xian22.start();
    }
}

 class xian1 extends Thread { 
        public void run()
        {
             for(int i=1;i<=5;i++)
           {  System.out.println( i+ "你好"+"     來自執行緒1");
            try{   sleep(200);   }
            catch(InterruptedException e)     //異常
           { System.out.println("Lefthand error.");}    
           } 
      } 
     }
      class xian2 extends Thread {
         public void run()
         {
              for(int i=1;i<=5;i++)
              {   System.out.println( i+ "你好"+"      來自執行緒2");
              try{   sleep(200);   }
              catch(InterruptedException e)//異常捕獲
              { System.out.println("Lefthand error.");}    
              }
          }
      }

xiancheng

3. 完善實驗十五 GUI綜合程式設計練習程式。

實驗總結

　　通過本週的學習我瞭解了執行緒的概念，並且瞭解了執行緒建立的兩種技術、執行緒的優先順序屬性及排程方法以及終止執行緒的方法，（1）用Thread類的子類建立執行緒（2）用Runnable()介面實現執行緒；理解了執行緒的優先順序屬性及排程方法和執行緒的七種狀態。但是這些知識掌握還不牢靠，需要課下多加練習。