//获取文件内的内容并排序public static  void copyFile() throws Exception{//创建File 对象File sourece = new File("/Desktop/pic/a.txt");//创建读字符流对象BufferedReader br = new BufferedReader(new FileReader(sourece));//一次读取一行String str = br.readLine();//将字符串转换成字符数组char[] ch = str.toCharArray();//将字符数组排序，底层访问ascii码for (int x = 0;x<ch.length;x++){for (int y = x+1;y<ch.length;y++){if (ch[x]>ch[y]){char temp = ch[x];ch[x] = ch[y];ch[y] = temp;}}}//将字符数组转换成字符串String strNew = new String(ch);//获取源文件的文件名String filename = sourece.getName();//System.out.print(filename);//将字符串切割String[] fileName = filename.split("\\.");//组合成新的字符串（新文件的名字）String newFile = fileName[0]+"1."+fileName[1];// System.out.print(newFile);//文件名已经确认、缺少盘符名称//创建File类将父路径，文件名放入去File targer = new File(sourece.getParent(),newFile);//创建文件写入流BufferedWriter bw = new BufferedWriter(new FileWriter(targer));//写入读取的字符串bw.write(strNew);//刷新字符流bw.flush();//关闭字符流bw.close();}