Java I/O

DataIO.java

package java_core.io.raw;

import java.io.*;

/**
 *
 * @author AARomanov1985
 */
public class DataIO {

    public static void main(String args[]) throws IOException {
        DataOutputStream out = new DataOutputStream(new FileOutputStream("data.dat"))
            out.writeUTF("Это тестовая строка");
            out.writeInt(100);
            out.writeDouble(12345.7676);
            out.writeBoolean(true);
        
        DataInputStream in = new DataInputStream(new FileInputStream("data.dat"))
            System.out.println(in.readUTF());
            System.out.println(in.readInt());
            System.out.println(in.readDouble());
            System.out.println(in.readBoolean());
        
    }
}

DirList.java

package java_core.io.raw;

import java.io.*;
import java.util.*;

/**
 *
 * @author AARomanov1985
 */
public class DirList {
    public static void main(String args[]){
        for (String s : dirList("d:\\")){
            System.out.println(s);
        }
    }

    public static String[] dirList(String path){
        File dir = new File(path);
        String[] list = dir.list();
        Arrays.sort(list);
        return list;
    }
}

FileBlock.java

package java_core.io.raw;

import java.io.*;
import java.nio.channels.*;
import java.util.concurrent.TimeUnit;
/**
 * Установка блокировки на файл
 */
public class FileBlock {
    public static void main(String[] args) throws Exception{
        try (FileOutputStream fos = new FileOutputStream("file.dat")) {
            FileLock fl = fos.getChannel().tryLock();
            if (fl !=null){
                System.out.println("Файл заблокирован");
                TimeUnit.MICROSECONDS.sleep(100);
                fl.release();
                System.out.println("Блокировка снята");
            }
        }
    }
}

FileCopyNIO.java

package java_core.io.raw;

import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import java.util.logging.*;

/**
 *
 * @author AARomanov1985
 */
public class FileCopyNIO {

    private static final int BSIZE = 65536*256;

    private static boolean copy(String filename, String copyname) {
        ByteBuffer buffer = ByteBuffer.allocate(BSIZE);
        try (FileChannel in = new FileInputStream(filename).getChannel();
                FileChannel out = new FileOutputStream(copyname).getChannel();) {
            long available;
            while ((available = in.size() - in.position()) > 0) {
                if (available < BSIZE) {
                    buffer = ByteBuffer.allocate((int) available);
                }
                in.read(buffer);
                buffer.flip();
                out.write(buffer);
                buffer.clear();
            }
        } catch (IOException e) {
            Logger.getGlobal().severe(e.getMessage());
            return false;
        }
        return true;
    }

}

MarkTest.java

package java_core.io.raw;
import java.io.*;
/**
 *
 * @author AARomanov1985
 */
public class MarkTest {
    public static void main(String args[])throws IOException{
        BufferedReader in = new BufferedReader(new FileReader("in.txt"));
        read(in);
        in.reset();
        System.out.println("Сброс");
        read(in);
    }

    private static void read(BufferedReader in) throws IOException{
        int c;
        while ((c=in.read())!=-1){
            System.out.println((char)c);
            if ((char)c=='\n'){
                in.mark(c);
                System.out.println("Метка!");
            }
        }
    }
}

SimpleTimer.java

package java_core.io.serial.raw.support;
import java.io.*;
/**
 * Пример расширенной сериализации
 */
public class SimpleTimer implements Externalizable{
    private byte hour;
    private byte min;
    private byte sec;

    public SimpleTimer(){

    }

    public SimpleTimer(String time){
        this.hour = (byte)Integer.parseInt(time.substring(0, 2));
        this.min = (byte)Integer.parseInt(time.substring(3, 5));
        this.sec = (byte)Integer.parseInt(time.substring(6, 8));
    }

    @Override
    public void writeExternal(ObjectOutput out) throws IOException {
        out.write(hour);
        out.write(min);
        out.write(sec);
    }

    @Override
    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
        this.hour = in.readByte();
        this.min = in.readByte();
        this.sec = in.readByte();
    }

    public int getHour() {
        return hour;
    }

    public void setHour(byte hour) {
        this.hour = hour;
    }

    public int getMin() {
        return min;
    }

    public void setMin(byte min) {
        this.min = min;
    }

    public int getSec() {
        return sec;
    }

    public void setSec(byte sec) {
        this.sec = sec;
    }
    
    public static void main(String[] args)throws IOException, ClassNotFoundException{
        SimpleTimer timer = new SimpleTimer("14:59:13");
        ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("SimpleTimer.data"));
        out.writeObject(timer);
        ObjectInputStream in = new ObjectInputStream(new FileInputStream("SimpleTimer.data"));
        SimpleTimer timer2 = (SimpleTimer)in.readObject();
        System.out.println(timer2.getHour()+":"+timer2.getMin()+":"+timer2.getSec());
    }
}

SimpleTimerTransient.java

package java_core.io.serial.raw.support;
import java.io.*;
/**
 * Сериализация полей, помеченных transient
 */
public class SimpleTimerTransient implements Serializable{
    private transient String Name;
    private byte hour;
    private byte min;
    private byte sec;

    public SimpleTimerTransient(String time){
        this.hour = (byte)Integer.parseInt(time.substring(0, 2));
        this.min = (byte)Integer.parseInt(time.substring(3, 5));
        this.sec = (byte)Integer.parseInt(time.substring(6, 8));
    }


    private void writeObject(ObjectOutputStream out) throws IOException {
        out.defaultWriteObject(); // Запуск сериализации по-умолчанию
        out.writeUTF(Name); // Запись transient-поля вручную
    }

    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
        in.defaultReadObject(); // Запуск десериализации по-умолчанию
        this.Name = in.readUTF(); // Восстановление transient-поля вручную
    }

    /*

    Игнорирование обычной сериализации:

    private void writeObject(ObjectOutputStream out) throws IOException {
        out.writeUTF(Name);
        out.write(hour);
        out.write(min);
        out.write(sec);
    }

    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
        this.Name = in.readUTF();
        this.hour = in.readByte();
        this.min = in.readByte();
        this.sec = in.readByte();
    }

    */

    public int getHour() {
        return hour;
    }

    public void setHour(byte hour) {
        this.hour = hour;
    }

    public int getMin() {
        return min;
    }

    public void setMin(byte min) {
        this.min = min;
    }

    public int getSec() {
        return sec;
    }

    public void setSec(byte sec) {
        this.sec = sec;
    }

    public String getName() {
        return Name;
    }

    public void setName(String Name) {
        this.Name = Name;
    }

    public static void main(String[] args) throws FileNotFoundException, IOException, ClassNotFoundException {
        SimpleTimerTransient timer = new SimpleTimerTransient("15:22:16");
        timer.setName("Таймер");
        System.out.println(timer.getHour()+":"+timer.getMin()+":"+timer.getSec());
        System.out.println(timer.getName());
        ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("SimpleTimer.data"));
        out.writeObject(timer);
        ObjectInputStream in = new ObjectInputStream(new FileInputStream("SimpleTimer.data"));
        SimpleTimerTransient timer2 = (SimpleTimerTransient)in.readObject();
        System.out.println(timer2.getHour()+":"+timer2.getMin()+":"+timer2.getSec());
        System.out.println(timer2.getName());
    }
}

/* Вывод:

15:22:16
Таймер
15:22:16
Таймер

*/

ThreadedEchoServer.java

package java_core.io.raw;

import java.io.*;
import java.net.*;
import java.util.*;

/**
 *
 * Пример простого сервера на порте 8189
 */
public class ThreadedEchoServer {

    public static void main(String[] args) {
        try {
            int i = 1;
            ServerSocket s = new ServerSocket(8189);
            while (true) {
                Socket in = s.accept();
                System.out.println("Spawing "+i);
                Runnable r = new ThreadedEchoHandler(in);
                Thread t = new Thread(r);
                t.start();
                i++;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}


class ThreadedEchoHandler implements Runnable{
    private Socket in;

    ThreadedEchoHandler(Socket in){
        this.in = in;
    }

    @Override
    public void run() {
       try{
           try{
               InputStream ins = in.getInputStream();
               OutputStream ous = in.getOutputStream();

               Scanner sc = new Scanner(ins);
               PrintWriter out = new PrintWriter(ous, true);
               out.println("Hello! Enter BYE to exit.");
               while(sc.hasNextLine()){
                   String line = sc.nextLine();
                   out.println("Echo: "+line);
                   if (line.equals("BYE")){
                       break;
                   }
               }
           }finally{
               in.close();
           }
       }catch(IOException e){
           e.printStackTrace();
       }
    }
}