java读取和复制文本文件的内容

//读取

import java.io.FileReader;

import java.io.IOException; 

import java.io.FileNotFoundException;

public class Test{

public static void main(String[] args){

try{

BufferedReader br = new BufferedReader(new FileReader("a.txt"));

String str;

while((str=br.readLine())!=null){

System.out.println(str);

}

}catch(FileNotFoundException e){

throw new RuntimeEXceprion(e);

}catch(IOException e){

throw new RuntimeEXceprion(e);

}

}

}

//复制文本文件的内容,第一种

public class Test1{

public static void main(String[] args){

try{

//封装数据源

BufferedReader br = new BufferedReader(new FileReader("a.txt"));

//封装目的地

BufferedWriter bw = new BufferedWriter(new FileWriter("b.txt"));

char[] ch =  new char[1024];

int len = 0;

while((len=br.read(ch))!=-1){

bw.write(ch,0,len);

   bw.flush();

}

bw.close();

br.close();

}catch(IOException e){

throw new RuntimeExceprion(e);

}

}

}

//第二种复制

public class Test2{

public static void main(String[] args){

try{

//封装数据源

BufferedReader br = new BufferedReader(new FileReader("a.txt"));

//封装目的地

BufferedWriter bw = new BufferedWriter(new FileWriter("b.txt"));

String str;

while((str=br.readLine())!=null){

bw.write(str);

bw.newLine();

   bw.flush();

}

bw.close();

br.close();

}catch(IOException e){

throw new RuntimeExceprion(e);

}

}

}