拷贝文本数据

        FileReader fr=new FileReader("buf.txt");    
        BufferedReader bur=new BufferedReader(fr);
        
        FileWriter fw=new FileWriter("coptest.txt");
        BufferedWriter buf=new BufferedWriter(fw);
        String str=null;
        while((str=bur.readLine())!=null){
            buf.write(str);
            buf.newLine();
            buf.flush();
        bur.close();
        buf.close();