一、读文件

import java.io.BufferedOutputStream;

import  java.io.BufferedReader;

import java.io.File;

import java.io.FileOutputStream;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

import java.io.OutputStreamWriter;

 

public void ReadFile(String filename) {

File file=new File(filename);

BufferedReader reader=null;

try{

reader=new BufferedReader(new FileReader(file));   //如果是读大文件  则  new BufferedReader(new FileReader(file),5*1024*1024);  即，设置缓存

String tempString=null;

while((tempString=reader.readLine())!=null)

{

//进行操作…..

}

reader.close();

}catch(IOException e){

e.printStackTrace();

}finally{

if(reader!=null)

{

try{

reader.close();

}catch(IOException e)

{

e.printStackTrace();

}

}

}

}

二、写文件

import java.io.BufferedOutputStream;

import  java.io.BufferedReader;

import  java.io.BufferedWriter;

import java.io.File;

import java.io.FileOutputStream;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

import java.io.OutputStreamWriter;

 

public void method1(String file,String content){

BufferedWriter out=null;

try{

out=new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file,true)));  //追加的方法

out.write(content);

out.write(“\r\n”);

}catch(IOException e){

e.printStackTrace();

}finally{

try{

out.close();

}catch(IOException e){

e.printStackTrace();

}

}

}

 

public void main(String[] args)

{

String filename=”D:\a.txt”;

File f=new File(filename);

if(f.exists()){

f.delete();

}

f.createNewFile();

String ss=”sssssss”;

method1(filename,ss);

}