Java IO

package day6.lab;

import java.io.File;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

import java.io.PrintStream;

public class IOTest {

public static void main(String[] args) throws IOException {

File f = new File("src/day5/lab2/Adder.java");

System.out.println(f.exists());

System.out.println(f.length());

FileReader fi = new FileReader("src/day5/lab2/Adder.java");

PrintStream ps  = System.out;  // 표준 출력(모니터)

FileWriter fw = new FileWriter("Adder_Backup.java");

int i;

while((i = fi.read()) != -1){

System.out.print((char)i);

fw.write(i);

}

fw.close();

fi.close();

}

}

package day6.lab;

import java.io.DataInputStream;

import java.io.DataOutputStream;

import java.io.FileInputStream;

import java.io.FileOutputStream;

public class IOTest2 {

public static void main(String[] args) throws Exception {

FileOutputStream fos = new FileOutputStream("aa.dat");

DataOutputStream dos = new DataOutputStream(fos);

dos.writeBoolean(true);

dos.writeBoolean(false);

dos.writeChars("dkdkdkdk");

dos.close();

fos.close();

FileInputStream fis = new FileInputStream("aa.dat");

DataInputStream dis = new DataInputStream(fis);

boolean d = dis.readBoolean();

System.out.println(d);

}

}

package day6.lab;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.FileNotFoundException;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

public class IOTest3 {

public static void main(String[] args) {

FileReader fr = null;

BufferedReader br = null;

FileWriter fw = null;

BufferedWriter bw = null;

try {

fr = new FileReader("src/day6/lab/IOTest.java");

br = new BufferedReader(fr);

fw = new FileWriter("IOTest.java");

bw = new BufferedWriter(fw);

String s = null;

while ((s = br.readLine()) != null) {

System.out.println(s);

bw.write(s);

bw.newLine();

}

} catch (FileNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} finally {

try {

if (br != null)

br.close();

if (fr != null)

fr.close();

if (bw != null)

bw.close();

if (fw != null)

fw.close();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

}