Bài toán đa luồng (MultiThreading in java) đọc File trong Java

#Thread3.java

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package lesson3;

import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Diep.Tran
 */
public class Thread3 extends Thread{
    SharedData sharedData;

    public Thread3(SharedData sharedData) {
        this.sharedData = sharedData;
    }

    @Override
    public void run() {
        while(!sharedData.isStop()) {
            synchronized(sharedData) {
                sharedData.notifyAll();
                try {
//                    while(sharedData.getCurrentThread() != SharedData.THREAD3) {
//                        sharedData.wait();
//                        
//                        if(sharedData.isStop()) {
//                            sharedData.notifyAll();
//                            System.out.println("T3 stop");
//                            return;
//                        }
//                    }
                    
                    while(!sharedData.isStop() && sharedData.getCurrentThread() != SharedData.THREAD3) {
                        sharedData.wait();
                    }
                    if(sharedData.isStop()) break;
                } catch (InterruptedException ex) {
                    Logger.getLogger(Thread3.class.getName()).log(Level.SEVERE, null, ex);
                }
                
                int number = sharedData.getNumber();
                System.out.println("BP: " + (number * number));
                sharedData.setCurrentThread(SharedData.THREAD1);
            }
        }
        
        System.out.println("T3 stop");
        synchronized(sharedData) {
            sharedData.notifyAll();
        }
    }
}

#Thread2.java

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package lesson3;

import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Diep.Tran
 */
public class Thread2 extends Thread{
    SharedData sharedData;

    public Thread2(SharedData sharedData) {
        this.sharedData = sharedData;
    }

    @Override
    public void run() {
        while(!sharedData.isStop()) {
            synchronized(sharedData) {
                sharedData.notifyAll();
                try {
//                    while(sharedData.getCurrentThread() != SharedData.THREAD2) {
//                        sharedData.wait();
//                        if(sharedData.isStop()) {
//                            sharedData.notifyAll();
//                            System.out.println("T2 stop");
//                            return;
//                        }
//                    }
                    while(!sharedData.isStop() && sharedData.getCurrentThread() != SharedData.THREAD2) {
                        sharedData.wait();
                    }
                    if(sharedData.isStop()) break;
                } catch (InterruptedException ex) {
                    Logger.getLogger(Thread2.class.getName()).log(Level.SEVERE, null, ex);
                }
                
                int number = sharedData.getNumber();
                System.out.printf("\nT2 (" + number + "): ");
                for (int i = 1; i <= number; i++) {
                    if(number % i == 0) {
                        System.out.printf(i + ", ");
                    }
                }
                System.out.println("");
                sharedData.setCurrentThread(SharedData.THREAD1);
            }
        }
        
        System.out.println("T2 stop");
        synchronized(sharedData) {
            sharedData.notifyAll();
        }
    }
}

#Thread1.java

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 * To change this template file, choose Tools | Templates
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package lesson3;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Diep.Tran
 */
public class Thread1 extends Thread{
    SharedData sharedData;

    public Thread1(SharedData sharedData) {
        this.sharedData = sharedData;
    }

    @Override
    public void run() {
        FileReader reader = null;
        BufferedReader bReader = null;
        
        try {
            reader = new FileReader("number.txt");
            bReader = new BufferedReader(reader);
            //Loai bo so N trong file number.txt
            bReader.readLine();
            
            while(!sharedData.isStop()) {
                synchronized(sharedData) {
                    String s = bReader.readLine();
                    if(s == null || s.isEmpty()) {
                        sharedData.setStop(true);
                        break;
                    }
                    int number = Integer.parseInt(s);
                    System.out.println("Number: " + number);
                    
                    sharedData.setNumber(number);
                    
                    sharedData.notifyAll();
                    try {
                        while(sharedData.getCurrentThread() != SharedData.THREAD1) {
                            sharedData.wait();
                        }
                    } catch (InterruptedException ex) {
                        Logger.getLogger(Thread1.class.getName()).log(Level.SEVERE, null, ex);
                    }
                }
            }
        } catch (FileNotFoundException ex) {
            Logger.getLogger(Thread1.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(Thread1.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            if(reader != null) {
                try {
                    reader.close();
                } catch (IOException ex) {
                    Logger.getLogger(Thread1.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
            
            if(bReader != null) {
                try {
                    bReader.close();
                } catch (IOException ex) {
                    Logger.getLogger(Thread1.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        }
        
        System.out.println("T1 stop");
        synchronized(sharedData) {
            sharedData.notifyAll();
        }
    }
}

#SharedData.java

/*
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package lesson3;

/**
 *
 * @author Diep.Tran
 */
public class SharedData {
    public static final int THREAD1 = 1;
    public static final int THREAD2 = 2;
    public static final int THREAD3 = 3;
    
    int number;
    boolean stop;
    int currentThread = THREAD1;
    
    public SharedData() {
        stop = false;
    }

    public int getNumber() {
        return number;
    }

    public void setNumber(int number) {
        this.number = number;
        
        if(number % 2 == 0) {
            currentThread = THREAD2;
        } else {
            currentThread = THREAD3;
        }
    }

    public boolean isStop() {
        return stop;
    }

    public void setStop(boolean stop) {
        this.stop = stop;
    }

    public int getCurrentThread() {
        return currentThread;
    }

    public void setCurrentThread(int currentThread) {
        this.currentThread = currentThread;
    }
}

#Main.java

/*
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package lesson3;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Diep.Tran
 */
public class Main {
    public static void main(String[] args) {
//        randomNumbers();
        SharedData sharedData = new SharedData();
        
        Thread1 t1 = new Thread1(sharedData);
        Thread3 t3 = new Thread3(sharedData);
        Thread2 t2 = new Thread2(sharedData);
        
        t1.start();
        t2.start();
        t3.start();
    }
    
    static void randomNumbers() {
        Random random = new Random();
        
        FileOutputStream fos = null;
        
        try {
            fos = new FileOutputStream("number.txt");
            
            int n = random.nextInt(90) + 10;
            byte[] b = String.valueOf(n + "\n").getBytes();
            fos.write(b);
            
            for (int i = 0; i < n; i++) {
                int v = random.nextInt(500) + 1;
                
                b = String.valueOf(v + "\n").getBytes();
                fos.write(b);
            }
        } catch (FileNotFoundException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            try {
                fos.close();
            } catch (IOException ex) {
                Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }
}