17일차

17일차

BufferedReader 와BufferedWriter 그리고 FileReader 와 FileWriter

FileReader 와 FileWriter 로 읽어온 데이터를

BufferedReader 와BufferedWriter 에 잠시 저장해 두는것.

예제 참조.

FileReaderTest.java

package hb.net.java_20151214; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.File; import java.io.FileInputStream; import java.io.FileWriter; import java.io.InputStreamReader; public class FileReaderTest { public static void main(String[] args) { String path="c:\\test\\"; try { File file = new File(path+"test2_copy.txt"); file.createNewFile(); // FileReader fr = new FileReader(path+"test.txt"); // BufferedReader br = new BufferedReader(f); // FileInputStream fis = new FileInputStream(path+"test.txt"); // BufferedReader br = new BufferedReader(fis); // 자 inputstream을 버퍼 reader로 읽고 싶은데 안되! 이럴때는 // InputStreamReader이란 것을 사용하자. FileInputStream fis = new FileInputStream(path+"test.txt"); // InputStreamReader isr = new InputStreamReader(fis); // BufferedReader br = new BufferedReader(isr); //혹은 BufferedReader br = new BufferedReader(new InputStreamReader(fis)); FileWriter fw = new FileWriter(file,true); BufferedWriter bw = new BufferedWriter(fw); String str = ""; while((str = br.readLine())!=null){ bw.write(str+"\r\n"); } bw.flush(); if(br != null)br.close(); else if(bw != null)bw.close(); else if(fis != null)fis.close(); else if(fw != null)fw.close(); } catch (Exception e) { e.printStackTrace(); } finally{ //예외에 관계없이 closing 작업시에는 finally 안에 기술할 수 있다. } } }

FileWriterTest.java

package hb.net.java_20151214; import java.io.BufferedWriter; import java.io.FileWriter; public class FileWriterTest { public static void main (String args[]){ try{ FileWriter fw= new FileWriter("c:\\test\\test2.txt",true); BufferedWriter bw = new BufferedWriter(fw); String message = "안녕하세요\r\n"; bw.write(message); bw.flush(); bw.close(); }catch(Exception e){ e.printStackTrace(); } } }

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