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

#Thread3.java

/*
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package java2.bt1105;

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

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

    @Override
    public void run() {
        SharedData sharedData = SharedData.getInstance();
        
        while(sharedData.isLive()) {
            synchronized(sharedData) {
                sharedData.notifyAll();
                try {
                    while(sharedData.getCurrentThread() != SharedData.THREAD_3 
                            && sharedData.isLive()) {
                        sharedData.wait();
                    }
                    if(!sharedData.isLive()) break;
                } catch (InterruptedException ex) {
                    Logger.getLogger(Thread2.class.getName()).log(Level.SEVERE, null, ex);
                }
                
                int rand = SharedData.getInstance().getN();
                System.out.println("T3 > " + rand * rand);
                
                sharedData.setCurrentThread(SharedData.THREAD_1);
            }
        }
        
        System.out.println("T3 stop");
    }
    
}

#Thread2.java

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package java2.bt1105;

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

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

    @Override
    public void run() {
        SharedData sharedData = SharedData.getInstance();
        
        while(sharedData.isLive()) {
            synchronized(sharedData) {
                sharedData.notifyAll();
                try {
                    while(sharedData.getCurrentThread() != SharedData.THREAD_2 
                            && sharedData.isLive()) {
                        sharedData.wait();
                    }
                    if(!sharedData.isLive()) break;
                } catch (InterruptedException ex) {
                    Logger.getLogger(Thread2.class.getName()).log(Level.SEVERE, null, ex);
                }
                
                int rand = SharedData.getInstance().getN();
                System.out.println("T2 > ");
                for (int i = 1; i <= rand; i++) {
                    if(rand % i == 0) {
                        System.out.print(i + " ");
                    }
                }
                System.out.println("");
                
                sharedData.setCurrentThread(SharedData.THREAD_1);
            }
        }
        
        System.out.println("T2 stop");
    }
    
}

#Thread1.java

/*
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package java2.bt1105;

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{

    @Override
    public void run() {
        try {
            Thread.sleep(100);
        } catch (InterruptedException ex) {
            Logger.getLogger(Thread1.class.getName()).log(Level.SEVERE, null, ex);
        }
        
        FileReader reader = null;
        BufferedReader bReader = null;
        SharedData sharedData = SharedData.getInstance();
        
        try {
            reader = new FileReader("student.txt");
            bReader = new BufferedReader(reader);
            
            bReader.readLine();
            String line;
            while((line = bReader.readLine()) != null) {
                synchronized(sharedData) {
                    //Dong bo du lieu
                    int rad = Integer.parseInt(line);
                    SharedData.getInstance().setN(rad);
                    System.out.println("T1 > " + rad);
                    
                    if(rad % 2 == 0) {
                        sharedData.setCurrentThread(SharedData.THREAD_2);
                    } else {
                        sharedData.setCurrentThread(SharedData.THREAD_3);
                    }
                    
                    sharedData.notifyAll();
                    try {
                        while(sharedData.getCurrentThread() != SharedData.THREAD_1) {
                            sharedData.wait();
                        }
                    } catch (InterruptedException ex) {
                        Logger.getLogger(Thread1.class.getName()).log(Level.SEVERE, null, ex);
                    }
                }
            }
        } catch (FileNotFoundException ex) {
            Logger.getLogger(Thread3.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(Thread3.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            if(bReader != null) {
                try {
                    bReader.close();
                } catch (IOException ex) {
                    Logger.getLogger(Thread3.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
            if(reader != null) {
                try {
                    reader.close();
                } catch (IOException ex) {
                    Logger.getLogger(Thread3.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        }
        
        SharedData.getInstance().setLive(false);
        
        synchronized(sharedData) {
            sharedData.notifyAll();
        }
        System.out.println("T1 stop");
    }
    
}

#SharedData.java

/*
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 * To change this template file, choose Tools | Templates
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package java2.bt1105;

/**
 *
 * @author Diep.Tran
 */
public class SharedData {
    public static final int THREAD_1 = 1;
    public static final int THREAD_2 = 2;
    public static final int THREAD_3 = 3;
    
    int n;
    boolean live = true;
    int currentThread = THREAD_1;
    
    private static SharedData instance = null;
    
    private SharedData() {
    }
    
    public synchronized static SharedData getInstance() {
        if(instance == null) {
            instance = new SharedData();
        }
        return instance;
    }

    public int getN() {
        return n;
    }

    public void setN(int n) {
        this.n = n;
    }

    public boolean isLive() {
        return live;
    }

    public void setLive(boolean live) {
        this.live = live;
    }

    public int getCurrentThread() {
        return currentThread;
    }

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

#Main.java

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
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package java2.bt1105;

import java.io.BufferedWriter;
import java.io.FileWriter;
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) {
        //createFile();
        Thread1 t1 = new Thread1();
        Thread2 t2 = new Thread2();
        Thread3 t3 = new Thread3();
        
        t1.start();
        t2.start();
        t3.start();
    }
    
    static void createFile() {
        FileWriter writer = null;
        BufferedWriter bWriter = null;
        
        Random random = new Random();
        int N = random.nextInt(90) + 10;
        
        try {
            writer = new FileWriter("student.txt");
            bWriter = new BufferedWriter(writer);
            
            bWriter.write(N + "\n");
            
            for (int i = 0; i < N; i++) {
                int rand = random.nextInt(500) + 1;
                bWriter.write(rand + "\n");
            }
        } catch (IOException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            if(bWriter != null) {
                try {
                    bWriter.close();
                } catch (IOException ex) {
                    Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
            if(writer != null) {
                try {
                    writer.close();
                } catch (IOException ex) {
                    Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        }
    }
}