자바 I/O Data input/output Stream 07

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
 
public class FileMain03 {
    public static void write() {
        FileOutputStream fos = null;
        DataOutputStream dos = null;
//        OutputStreamWriter osw = null;
        
        try {
            fos = new FileOutputStream("iotest/writer.txt");
            int num = 97;            
//            fos.write(num);
            dos = new DataOutputStream(fos);
            
            dos.writeInt(num);
            dos.writeDouble(num);
            dos.writeChar(num);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                fos.close();
            } catch(Exception e) {
                e.printStackTrace();
            }
            try {
                dos.close();
            } catch (Exception e) {
                e.printStackTrace();
            } 
             
            
        }
    }
    public static void read() {
        FileInputStream fis = null;
        DataInputStream dis = null;
         
        
        try {
            fis = new FileInputStream("iotest/writer.txt");
         
            dis = new DataInputStream(fis);
            
            int i = dis.readInt();
            double d = dis.readDouble();
            char ch = dis.readChar();
            
            System.out.println("정수 : " + i);
            System.out.println("실수 : " + d);
            System.out.println("문자 : " + ch);
             
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try{
                fis.close();
            } catch(Exception e) {
                e.printStackTrace();
            }
            try {
                dis.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
             
        }
        
    }
    public static void main(String[] args) {
        write();
        read();
        
    }
}