[Java] Input/Output Stream

package io2;

import java.io.BufferedOutputStream;
import java.io.FileOutputStream;

public class BufferedOutputStreamTest {

	public static void main(String[] args) throws Exception{
		//파일을 인수로 FileOutputStream 객체를 생성하고
		FileOutputStream fos = new FileOutputStream("alpha.txt");
		
		//그 객체를 인수로 BufferdOutputStream 객체를 생성한다.
		BufferedOutputStream bos = new BufferedOutputStream(fos);
		
		
		//a~z까지 문자를 기록한다. 버퍼를 사용하기 때문에
		//실제 파일 기록되는 것이 아니라 버터에 기록된다.
		for(int i ='a'; i<='z'; i++) {
			bos.write(i);
		}
		
		//버퍼에 기록되어 데이터를 실제 파일에 기록한다.
		bos.flush();
		
		fos.close();
		bos.close();
		
		
		
	}

}​

package io2;

import java.io.FileReader;
import java.io.FileWriter;

public class FileWriterTest {

	public static void main(String[] args) throws Exception {
		FileReader fr = new FileReader("sample.txt");
		FileWriter fw = new FileWriter("out2.txt", true);
		
		int input = 0;
		
		while((input = fr.read())!=-1) {
			fw.write(input);
		}
		
		fr.close();
		fw.close();
		
		
	}

}​

package io2;

import java.io.FileInputStream;
import java.io.FileOutputStream;

public class FileOutputStreamTest {

	public static void main(String[] args) throws Exception{
		FileInputStream fis = new FileInputStream("sample.txt");
		FileOutputStream fos = new FileOutputStream("out.txt");
		
		int input = 0;
		
		while((input = fis.read())!=-1) {
			fos.write(input);
		}
		
		fos.close();
		fis.close();
		
		
		
	}

}

package io2;

import java.io.InputStream;
import java.io.OutputStream;

public class OutputStreamTest {

	public static void main(String[] args) throws Exception{
		InputStream is = System.in;
		OutputStream out = System.out;
		
		System.out.println("데이터를 입력하세요");
		
		int input = is.read();
		System.out.println("실제 입력된 데이터 : "+ input);
		
		System.out.println("출력 데이터 : ");
		out.write((char)input);
		
		out.close();
	}

}​

package io2;

import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

public class OutputStreamWriterTest {

	public static void main(String[] args) throws Exception{
		char[] arr = new char[10];
		
		InputStreamReader isr = new InputStreamReader(System.in);
		OutputStreamWriter osw = new OutputStreamWriter(System.out);
		
		System.out.println("데이터를 입력하세요 : ");
		
		int input = isr.read(arr);
		
		System.out.println("실제 입력된 글자 : ");
		osw.write(arr);
		osw.close();
		
	}

}

package io;

import java.io.BufferedInputStream;
import java.io.FileInputStream;

public class BufferedInputStreamTest {

	public static void main(String[] args) throws Exception{
		int inputData = 0;
		
		FileInputStream fis = new FileInputStream("sample.txt");
		BufferedInputStream bis = new BufferedInputStream(fis);
		
		while((inputData = bis.read()) != -1) {
			System.out.print((char)inputData);
		}
	
		bis.close();
		fis.close();
	}

}​

package io;

import java.io.BufferedReader;
import java.io.FileReader;

public class BufferedReaderTest {

	public static void main(String[] args) throws Exception {
		String inputData = null;
		
		FileReader fir = new FileReader("sample.txt");
		BufferedReader br = new BufferedReader(fir);
		
		while((inputData = br.readLine())!=null) {
			System.out.println(inputData);
		}
		
		br.close();
	}

}

package io;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

public class FileReaderTest {

	public static void main(String[] args) {
		FileReader file = null;
		int inputData = 0;
		
		try{
			file = new FileReader("sample.txt");
			
			while((inputData =file.read())!= -1) {
				System.out.print((char)inputData);
			}
		}catch(FileNotFoundException e) {
			e.printStackTrace();
		}catch(IOException e){
			e.printStackTrace();
		}finally {
			try {
				file.close();
			}catch(IOException e) {
				e.printStackTrace();
			}
		}
		
		
	}

}​

package io;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class FileInputStremTest {

	public static void main(String[] args) {
		int inputData = 0;
		
		FileInputStream fis = null;
		
		try {
			fis = new FileInputStream("sample.txt");
			int cnt = 0;
			while((inputData = fis.read()) != -1) {
				System.out.print((char)inputData);
				cnt++;
			}
			System.out.println("\ncnt : "+cnt);
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		}catch(IOException e){
			e.printStackTrace();
		}finally {
			try {
				fis.close();
			}catch(IOException e) {
				e.printStackTrace();
			}
		}
		
	}

}

package io;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class InputStreamReaderTest {

	public static void main(String[] args) {
		InputStream is = System.in;
		InputStreamReader isr  = new InputStreamReader(is);
		
		int inputData = 0;
		
		System.out.println("데이터를 입력하세요");
		
		try{
			inputData = isr.read();
		}catch(IOException e) {
			e.printStackTrace();
		}
		
		System.out.println("실제 입력된 데이터 : "+ (char)inputData);
		
	}

}​

package io;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class InputStreamReaderTest2 {

	public static void main(String[] args) {
		InputStream is = System.in;
		InputStreamReader isr  = new InputStreamReader(is); //InputStream이 준 1바이트 + InputStream이 준  1바이트 모두를 저장하는 역할
		
		int inputData = 0; //몇글자가 입력되었는지 글자 개수를 저장하는 변수
		char[] temp = new char[10];
		
		System.out.println("데이터를 입력하세요");
		
		try {
			inputData = isr.read(temp);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		System.out.println("inputData : " +inputData);
		for(int i =0; i<inputData; i++) {
			System.out.println((int)temp[i]);
		}
	
	}

}

package io;

import java.io.IOException;
import java.io.InputStream;

public class InputStreamTest {

	public static void main(String[] args) {
		InputStream is = System.in;
		int inputData = 0;
		
		System.out.println("데이터를 입력하세요 : ");

		try {
			inputData = is.read();
		}catch (IOException e) {
			e.printStackTrace();
		}
		
		
		System.out.println("실제 입력된 데이터(정수) : "+inputData);
		System.out.println("실제 입력된 데이터(문자) : "+ (char)inputData);
		
		
		
	}

}