FileReader & BufferedReader & ObjectOutputStream & ObjectInputStream

// 파일을 입력받아 그 내용을 출력
import java.io.*;

public class object {
 public static void main(String arg[])throws IOException{
 
  File f = new File("ccc.txt");
  FileReader fr = new FileReader(f);
  BufferedReader br = new BufferedReader(fr);
 
  while(true)
  {
   String s = br.readLine();
   if(s==null) break;
   System.out.println(s);
  }
  br.close();
 }
}


============================================================================
// 객체 입력
import java.io.*;

class AAA implements Serializable{ // 객체 직렬화
 int x = 100;
 int y = 200;
 int z = 300;
}

public class object {
 public static void main(String arg[])throws IOException{
  AAA aa = new AAA();
  File f = new File("ddd.txt");
  FileOutputStream fos = new FileOutputStream(f);
  BufferedOutputStream bos = new BufferedOutputStream(fos);
  ObjectOutputStream oos = new ObjectOutputStream(bos);
 
  oos.writeObject(aa);
  oos.close();
 
  System.out.println("출력 완료");
 }
}

============================================================================
// 객체 출력
import java.io.*;

class AAA implements Serializable{ // 객체 직렬화
  int x = 100;
  int y = 200;
  int z = 300;
 }

public class object {
 public static void main(String arg[])throws IOException{
  File f = new File("ddd.txt");
  FileInputStream fis = new FileInputStream(f);
  BufferedInputStream bis = new BufferedInputStream(fis);
  ObjectInputStream ois = new ObjectInputStream(bis);
 
  Object obj = null;
  try{
   obj = ois.readObject();
  }catch(ClassNotFoundException e){}
 
  AAA ap = (AAA)obj;
  System.out.println(ap.x);
  System.out.println(ap.y);
  System.out.println(ap.z);
 }
}