IO流之Demo

使用io流，倒序输出数组元素：

 public static void main(String[] args) throws FileNotFoundException  {
		try {
		  int data_arr[] = {12,31,56,23,27,1,43,65,4,99};
		  //定义输入输出流，定义BufferedWriter,BufferedReader
		  //字节流转为字符流
		  DataOutputStream douts = new DataOutputStream(new BufferedOutputStream(new FileOutputStream("E:/1.txt")));
		  BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(douts));
			
		  DataInputStream dins  = new DataInputStream(new BufferedInputStream(new FileInputStream("E:/1.txt")));
		  BufferedReader br = new BufferedReader(new InputStreamReader(dins));
		  
		  //写入操作
		  String ins = "";
		  for(int i =0;i<data_arr.length;i++) {
			  ins += data_arr[i]+"\n";
		  }
		  bw.write(ins);
		  bw.flush();
		  
		  //读取操作
		  String outs = "";
		  char c=0;
		  while(c != (char)-1) {
			  outs = c +br.readLine()+ ","+outs.trim();
			  c = (char)br.read();
		  }
          
		  System.out.println("逆序输出：\n"+outs.substring(0, outs.length()-1));
		  bw.close();
          br.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
}