IO流

 1 package Suchas;
 2  import java.io.*;
 3 
 4 public class FileIO 
 5 {
 6     public FileIO(String str)
 7      {
 8          File f = new File("data.txt");
 9          try 
10          {
11              File file = new File("data.txt");
12              FileWriter fw = new FileWriter(file);
13              BufferedWriter bw = new BufferedWriter(fw);
14             bw.write(str);
15              bw.close();
16          } catch (IOException e)
17          {
18             e.printStackTrace();
19         }
20     }
21     public static void main(String[] args) 
22     {
23          String str = "12345abcdef@#%&*软件工程";
24          new File(str);
25  
26      }
27  
28  }

 1 package Suchas;
 2  import java.io.BufferedReader;
 3  import java.io.File;
 4  import java.io.FileNotFoundException;
 5  import java.io.FileReader;
 6  import java.io.IOException;
 7  public class Filedemo
 8  {
 9      public Filedemo()
10      {
11          File f = new File("data.txt");
12              try {
13                  BufferedReader br = new BufferedReader(new FileReader(f));
14                 String str = br.readLine();
15                  System.out.println(str);
16                  br.close();
17             } catch (FileNotFoundException e) 
18              {
19                  e.printStackTrace();
20              } catch (IOException e) 
21              {
22                  e.printStackTrace();
23              }    
24      }
25      public static void main(String[] args) 
26      {
27          new Filedemo();
28  
29      }
30  
31  }