public static void main(String[]args)
{
    File head=new File("D:/d/b");
    File last=new File("D:/d/vv");

    try(BufferedReader breader=new BufferedReader(new FileReader(head));
            BufferedWriter bwriter=new BufferedWriter(new FileWriter(last))) {

        //用新方法逐行读取
        String line=null;
        while((line=breader.readLine())!=null)
        {
            bwriter.write(line);//逐行写出
            bwriter.newLine(); //每行写入一个换行符
            bwriter.flush();
        }

    }catch(FileNotFoundException e)
    {
        e.printStackTrace();
    }catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

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