Java NIO——6 基于非阻塞程式設計UDP NIO的例子

轉自 http://blog.csdn.net/chenxuegui1234/article/details/17981203

好吧，承接上篇文章，下面給出一個udp不可靠無連接配接的例子，他的次傳送都是一個udp封包，不向上面文章中tcp是基于流的

代碼：

Server:

[java]  view plain  copy  print ?

1. public class UDPServer  
2. {  
3.     DatagramChannel channel;  
4.     Selector selector;  
5.     public void work()  
6.     {  
7.         try  
8.         {  
9.             // 打開一個UDP Channel  
10.             channel = DatagramChannel.open();  
11.             // 設定為非阻塞通道  
12.             channel.configureBlocking(false);  
13.             // 綁定端口  
14.             channel.socket().bind(new InetSocketAddress(8080));  
15.             // 打開一個選擇器  
16.             selector = Selector.open();  
17.             channel.register(selector, SelectionKey.OP_READ);  
18.         } catch (Exception e)  
19.         {  
20.             e.printStackTrace();  
21.         }  
22.         ByteBuffer byteBuffer = ByteBuffer.allocate(65536);  
23.         while (true)  
24.         {  
25.             try  
26.             {  
27.                 // 進行選擇  
28.                 int n = selector.select();  
29.                 if (n > 0)  
30.                 {  
31.                     // 擷取以選擇的鍵的集合  
32.                     Iterator iterator = selector.selectedKeys().iterator();  
33.                     while (iterator.hasNext())  
34.                     {  
35.                         SelectionKey key = (SelectionKey) iterator.next();  
36.                         // 必須手動删除  
37.                         iterator.remove();  
38.                         if (key.isReadable())  
39.                         {  
40.                             DatagramChannel datagramChannel = (DatagramChannel) key  
41.                                     .channel();  
42.                             byteBuffer.clear();  
43.                             // 讀取  
44.                             InetSocketAddress address = (InetSocketAddress) datagramChannel  
45.                                     .receive(byteBuffer);  
46.                             System.out.println(new String(byteBuffer.array()));  
47.                             // 删除緩沖區中的資料  
48.                             byteBuffer.clear();  
49.                             String message = "data come from server";  
50.                             byteBuffer.put(message.getBytes());  
51.                             byteBuffer.flip();  
52.                             // 發送資料  
53.                             datagramChannel.send(byteBuffer, address);  
54.                         }  
55.                     }  
56.                 }  
57.             } catch (Exception e)  
58.             {  
59.                 e.printStackTrace();  
60.             }  
61.         }  
62.     }  
63.     public static void main(String[] args)  
64.     {  
65.         new UDPServer().work();  
66.     }  
67. }  

用戶端：

[java]  view plain  copy  print ?

1. public class UDPClient  
2. {  
3.     DatagramChannel channel;  
4.     Selector selector;  
5.     public void work()  
6.     {  
7.         try  
8.         {  
9.             // 開啟一個通道  
10.             channel = DatagramChannel.open();  
11.             channel.configureBlocking(false);  
12.             SocketAddress sa = new InetSocketAddress("localhost", 8080);  
13.             channel.connect(sa);  
14.         } catch (Exception e)  
15.         {  
16.             e.printStackTrace();  
17.         }  
18.         try  
19.         {  
20.             selector = Selector.open();  
21.             channel.register(selector, SelectionKey.OP_READ);  
22.             channel.write(Charset.defaultCharset().encode("data come from client"));  
23.         } catch (Exception e)  
24.         {  
25.             e.printStackTrace();  
26.         }  
27.         ByteBuffer byteBuffer = ByteBuffer.allocate(100);  
28.         while (true)  
29.         {  
30.             try  
31.             {  
32.                 int n = selector.select();  
33.                 if (n > 0)  
34.                 {  
35.                     Iterator iterator = selector.selectedKeys().iterator();  
36.                     while (iterator.hasNext())  
37.                     {  
38.                         SelectionKey key = (SelectionKey) iterator.next();  
39.                         iterator.remove();  
40.                         if (key.isReadable())  
41.                         {  
42.                             channel = (DatagramChannel) key.channel();  
43.                             channel.read(byteBuffer);  
44.                             System.out.println(new String(byteBuffer.array()));  
45.                             byteBuffer.clear();  
46.                             channel.write(Charset.defaultCharset().encode(  
47.                                     "data come from client"));  
48.                         }  
49.                     }  
50.                 }  
51.             } catch (Exception e)  
52.             {  
53.                 e.printStackTrace();  
54.             }  
55.         }  
56.     }  
57.     public static void main(String[] args)  
58.     {  
59.         new UDPClient().work();  
60.     }  
61. }