学习打卡第二天

 1 import java.io.IOException;
 2 
 3 public class IOTest {
 4 
 5     public static void main(String[] args) {
 6         byte[] buffer = new byte[1024];
 7         try 
 8         {
 9             int len = System.in.read(buffer);
10             String s = new String(buffer , 0 , len);
11             System.out.println("接收到了："+len+"个字节");
12             System.out.println(s);
13             System.out.println("字符串长度为："+s.length());
14         }catch(IOException e) 
15         {
16             
17         }
18         
19 
20     }
21 
22 }

 1 import java.io.BufferedInputStream;
 2 import java.io.BufferedOutputStream;
 3 import java.io.DataInputStream;
 4 import java.io.DataOutputStream;
 5 import java.io.FileInputStream;
 6 import java.io.FileNotFoundException;
 7 import java.io.FileOutputStream;
 8 import java.io.IOException;
 9 
10 public class IOTest1 {
11 
12     public static void main(String[] args) {
13         byte[] buffer = new byte[1024];
14         try {
15             DataOutputStream out = new DataOutputStream(
16                     new BufferedOutputStream(
17                             new FileOutputStream("a.dat")));
18             int i = 0xface;
19             out.writeInt(i);
20             out.close();
21             DataInputStream in = new DataInputStream(
22                     new BufferedInputStream(
23                             new FileInputStream("a.dat")));
24             int j = in.readInt();
25             System.out.println(j);
26         } catch (FileNotFoundException e) {
27             // TODO Auto-generated catch block
28             e.printStackTrace();
29         } catch (IOException e) 
30         {
31             // TODO Auto-generated catch block
32             e.printStackTrace();
33         }
34 
35     }
36 
37 }