Console & File I/O

import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
  FileOutputStream fos1 = new FileOutputStream(FileDescriptor.out);
  File f = new File("aaa.txt");
  FileOutputStream fos2 = new FileOutputStream(f);
 
  byte by[] = new byte[]{'H','e','l','l','o',' ','J','A','V','A'};
   
  fos1.write(by);
  fos2.write(by);
 
  fos1.close();
  fos2.close();
 }
}

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import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
  FileOutputStream fos1 = new FileOutputStream(new File("bbb.txt"),false);
                                                                   // (FileDescriptor.out);
  BufferedOutputStream bos1 = new BufferedOutputStream(fos1);
  DataOutputStream dos1 = new DataOutputStream(bos1);
 
  dos1.writeInt(20); // 출력시 글자가 깨짐
  dos1.writeDouble(12.34); // 출력시 글자가 깨짐
  dos1.flush(); // 버퍼비우기 // 출력시 글자가 깨짐
 
  dos1.writeChar('A');
  dos1.writeByte('\n');
  dos1.writeByte('B');
  dos1.close();
 }
}

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import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
  FileInputStream fis1 = new FileInputStream(new File("aaa.txt"));
 
  while(true){
   int x = fis1.read();
   if(x == -1)
    break;
   System.out.print((char)x);
  }
  fis1.close();
 }
}

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import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
  File f = new File("bbb.txt");
  FileInputStream fis = new FileInputStream(f);
  BufferedInputStream bis = new BufferedInputStream(fis);
  DataInputStream dis = new DataInputStream(bis);
 
  int a = dis.readInt();
  double b = dis.readDouble();
  char c = dis.readChar();
  byte d = dis.readByte();
  byte e = dis.readByte();
  dis.close();
 
  System.out.println("a = "+a);
  System.out.println("b = "+b);
  System.out.println("c = "+c);
  System.out.println("d = "+d);
  System.out.println("e = "+(char)e);
 }
}

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import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
  File f = new File("bbb.txt");
  FileInputStream fis = new FileInputStream(f);
  BufferedInputStream bis = new BufferedInputStream(fis);
  DataInputStream dis = new DataInputStream(bis);
 
  while(true){
   int x = dis.read();
   if(x == -1)
    break;
   System.out.print(x);
  }
  dis.close();
 }
}

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// 출력시 글자가 깨지지 않는다.
import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
  OutputStreamWriter osw = new OutputStreamWriter(System.out);
  BufferedWriter bw = new BufferedWriter(osw);
  PrintWriter pw = new PrintWriter(bw);
 
  pw.println(10);
  pw.println("test 안뇽하세요~");
 
  pw.close();
 
 }
}

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// 파일 생성과 출력
import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
  File f = new File("ccc.txt");
  FileWriter fw = new FileWriter(f);
  BufferedWriter bw = new BufferedWriter(fw);
  PrintWriter pw = new PrintWriter(bw);
 
  pw.println(10);
  pw.println("안뇽하세요~");
  pw.close();
 
 }
}