[객체(16)] 입출력, 스트림

💫 실습1

 

package com.kh.p2.filter.controller;

import java.io.*;

public class Filter {
	public void consoleInOut() {
		
	}
	public void buf() {
		
	}
	public void data() {
		FileOutputStream fout = null;
		FileInputStream fin = null;
		DataOutputStream dout = null;
		DataInputStream din = null;
		
		try {
			fout = new FileOutputStream("member.txt");
			fin = new FileInputStream("member.txt");
			dout = new DataOutputStream(fout);
			din = new DataInputStream(fin);
			
			//파일에 자료형별로 기록
			dout.writeUTF("홍길동");
			dout.writeChar('남');
			dout.writeInt(32);
			dout.writeUTF("유관순");
			dout.writeChar('여');
			dout.writeInt(21);
			dout.writeUTF("장보고");
			dout.writeChar('남');
			dout.writeInt(27);
			
			while(true) {
				System.out.println(din.readUTF() + ", " + din.readChar() + ", " +din.readInt());
			}
			
		}catch(EOFException e) {
			System.out.println("파일 읽기 완료");
		}
		catch(IOException e) {
			e.printStackTrace();
			
		}finally {
			try {
				fout.close();
				fin.close();
				dout.close();
				
			}catch(IOException e) {
				
			}
		}
		
	}
	public void bufData() {
		FileInputStream fin = null;
		BufferedInputStream bin = null;
		DataInputStream din = null;
		
		try {
			fin = new FileInputStream("member.txt");
			bin = new BufferedInputStream(fin);
			din = new DataInputStream(bin);
			
			System.out.println(din.readUTF());
			
		}catch(FileNotFoundException e) {
			System.out.println("파일을 찾을 수 없습니다.");
		}catch(IOException e) {
			e.printStackTrace();
		}
	}
	public void reWri() {
		File file = new File("exam.txt");
		try(FileReader fr = new FileReader(file)) {
			int check = 0;
			while((check = fr.read()) != -1) {
				System.out.print((char)check);
			}
		}catch (FileNotFoundException e) {
			System.out.println("파일이 없습니다.");
		}catch(IOException e) {
			System.out.println(e);
		}
		
		//보조스트림(BufferedWriter, BufferedReader)을 달고 쓰자
		try(BufferedWriter bw = new BufferedWriter(new FileWriter("fileReWri.txt"));
				BufferedReader br = new BufferedReader(new FileReader("fileReWri.txt"))) {
			
			//bw.write("첫째줄\n둘째줄\n셋째줄");
			
			bw.write("첫째줄");
			bw.newLine();
			bw.write("둘째줄");
			bw.newLine();
			bw.write("셋째줄");
			bw.newLine();
			
			bw.flush(); //close 전이므로 flush를 안해주면 버퍼에 쌓여있는 상태이다.
			
			String str;
			while((str=br.readLine())!=null) {
				System.out.println(str);
			}
			
		}catch(IOException e) {
			e.printStackTrace();
		}
	}
}

 

package com.kh.p2.filter.run;

import com.kh.p2.filter.controller.Filter;

public class Run {
	public static void main(String[] args) {
		Filter f = new Filter();
		
		//콘솔 입출력(표준 입출력)
		//f.consoleInOut();
		
		//Buffered 보조 스트림
		//f.buf();
		
		//Data 보조 스트림 & try with resource문
		f.data();
		
		//Buffered & Data 보조 스트림
		f.bufData();
		
		f.reWri();
	}
}
/*
홍길동, 남, 32
유관순, 여, 21
장보고, 남, 27
파일 읽기 완료
홍길동
파일이 없습니다.
첫째줄
둘째줄
셋째줄
*/

 

 

💫 실습2

 

package com.kh.p3.object.model.vo;

import java.io.Serializable;

public class Phone implements Serializable{
	
	/**
	 * 
	 */
	private static final long serialVersionUID = -2410441448169889016L;
	private String maker;
	private int price;
	public Phone() {
		super();
	}
	public Phone(String maker, int price) {
		super();
		this.maker = maker;
		this.price = price;
	}
	@Override
	public String toString() {
		return "Phone [maker=" + maker + ", price=" + price + "]";
	}
}

 

package com.kh.p3.object.model.vo;

import java.io.Serializable;

public class Student implements Serializable{
	/**
	 * 
	 */
	private static final long serialVersionUID = -2795709242007578249L;
	private String name;
	private int age;
	private char gender;
	private Phone ph;
	public Student() {
		
	}
	public Student(String name, int age, char gender, Phone ph) {
		this.name = name;
		this.age = age;
		this.gender = gender;
		this.ph = ph;
	}
	@Override
	public String toString() {
		return "Student [name=" + name + ", age=" + age + ", gender=" + gender + ", ph=" + ph + "]";
	}
}

 

package com.kh.p3.object.model.vo;

import java.io.Serializable;

public class Teacher implements Serializable{
	/**
	 * 
	 */
	private static final long serialVersionUID = 6964533574688168950L;
	private String classR;
	private String name;
	public Teacher() {
		super();
	}
	public Teacher(String classR, String name) {
		super();
		this.classR = classR;
		this.name = name;
	}
	@Override
	public String toString() {
		return "Teacher [classR=" + classR + ", name=" + name + "]";
	}
}

 

package com.kh.p3.object.run;

import java.io.*;

import com.kh.p3.object.model.vo.Phone;
import com.kh.p3.object.model.vo.Student;
import com.kh.p3.object.model.vo.Teacher;

public class Run {
	//직렬화, 역직렬화
	public static void main(String[] args) {
		Phone[] ph = {new Phone("삼성", 70), new Phone("LG", 65), new Phone("화웨이", 40)};
		Student[] st = {new Student("학생1", 18, '남', ph[0]),
				new Student("학생2", 17, '여', ph[1]),
				new Student("학생3", 19, '남', ph[2])};
		Teacher tc = new Teacher("S", "김용승");
		
		try(ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("student.txt"));
				ObjectInputStream ois = new ObjectInputStream(new FileInputStream("Student.txt"))) {
			
			for(int i=0;i<st.length;i++) {
				oos.writeObject(st[i]);
			}
			oos.writeObject(tc);
			//Student형 다음 Teacher형
			
			for(int i=0 ; i<st.length;i++) {
				System.out.println((Student)ois.readObject());
			}
			System.out.println(ois.readObject());
		
		}catch(ClassNotFoundException e) {
			e.printStackTrace();
		}
		catch(IOException e) {
			e.printStackTrace();
		}
	}
}
/*
Student [name=학생1, age=18, gender=남, ph=Phone [maker=삼성, price=70]]
Student [name=학생2, age=17, gender=여, ph=Phone [maker=LG, price=65]]
Student [name=학생3, age=19, gender=남, ph=Phone [maker=화웨이, price=40]]
Teacher [classR=S, name=김용승]
*/