package com.hanqi.io;

 import java.io.*;

 public class IoDemo {

     public static void main(String[] args) {

         try{

             File file = new File("e:/test.txt");

             // 如果文件不存在

             if (!file.exists())

             {

                 file.createNewFile();

                 System.out.println("创建文件成功");

             }

             //构造输出流

             //覆盖写入

             FileWriter fw = new FileWriter(file);

             fw.write("aaaaaaaaaa");

             fw.close();

             System.out.println("写入文件完成");

             //字符输入流

             FileReader fr = new FileReader(file);

             char[] c = new char[1024];

             String str = "";

             int i = 0 ;

             while(( i = fr.read(c)) > 0)

             {

                 str += new String(c,0,i);

             }

             System.out.println("str = " + str);

             }

             catch (Exception e)

         {

                 // TODO 自动生成的 catch 块

                 e.printStackTrace();

             }

         File file1 = new File("e:/IoDemo.txt");

         try

         {

             file1.createNewFile();

    FileOutputStream fos = new FileOutputStream(file1);

             String str = "aaaaaaaaaa";

             //把数据源转换成byte[]数组

             byte [] b  = str.getBytes();

             //写入数据

             fos.write(b);

             //关闭流，释放文件

             fos.close();

         }

         catch (IOException e)

         {

             e.printStackTrace();

         }

         }

     }