java 字符流writer、reader基本操作及理解

来源：互联网发布：淘宝权冠军打野编辑：程序博客网时间：2024/06/05 17:24

字符和字节有什么区别，额……这个我也不知道。

1、基本操作实例

import java.io.*;public class CharDemo{public static void main(String[] args){File f=new File("F:\\workspace\\Javaprj\\test.txt");Writer out=null;Reader in=null;try{out=new FileWriter(f);String str="Hello World!!!";out.write(str);System.out.println("The string "+"\"Hello World!!!\""+" has been written into "+f.getName()+".");out.close();in=new FileReader(f);char[] buf=new char[1024];int num=in.read(buf);if(num!=-1){System.out.println("The string \""+ new String(buf,0,num) +"\" has been read from the file "+f.getName()+".");}else{System.out.println("The file \""+f.getName()+"\" is empty!");}}catch(IOException e){e.printStackTrace();}}}

2、注意的问题

将out.close();注释掉

import java.io.*;public class CharDemo{public static void main(String[] args){File f=new File("F:\\workspace\\Javaprj\\test.txt");Writer out=null;Reader in=null;try{out=new FileWriter(f);String str="Hello World!!!";out.write(str);System.out.println("The string "+"\"Hello World!!!\""+" has been written into "+f.getName()+".");//out.close();in=new FileReader(f);char[] buf=new char[1024];int num=in.read(buf);if(num!=-1){System.out.println("The string \""+ new String(buf,0,num) +"\" has been read from the file "+f.getName()+".");}else{System.out.println("The file \""+f.getName()+"\" is empty!");}}catch(IOException e){e.printStackTrace();}}}

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