学步园

TCP服务器端

package org.bruce.basic;</p> <p>import java.io.DataInputStream;<br /> import java.io.IOException;<br /> import java.net.Socket;<br /> import java.net.UnknownHostException;</p> <p>public class TestClient {</p> <p> public static void main(String[] args) {<br /> Socket s = null;</p> <p> try {<br /> s = new Socket("127.0.0.1", 8888);<br /> DataInputStream dis = new DataInputStream(s.getInputStream());<br /> System.out.println(dis.readUTF());<br /> dis.close();<br /> s.close();<br /> } catch (UnknownHostException e) {<br /> e.printStackTrace();<br /> } catch (IOException e) {<br /> e.printStackTrace();<br /> }<br /> }</p> <p>}<br />

TCP客户端

package org.bruce.basic;</p> <p>import java.io.DataOutputStream;<br /> import java.io.IOException;<br /> import java.net.ServerSocket;<br /> import java.net.Socket;</p> <p>public class TestServer {<br /> public static void main(String[] args) {<br /> ServerSocket ss = null;</p> <p> try {<br /> ss = new ServerSocket(9999);<br /> } catch (IOException e) {<br /> e.printStackTrace();<br /> }</p> <p> try {<br /> while(true) {<br /> Socket s = ss.accept();<br /> System.out.println("a client connect!");<br /> DataOutputStream dos = new DataOutputStream(s.getOutputStream());<br /> dos.writeUTF("IPAddress = " + s.getInetAddress() + " Port = " + s.getPort());<br /> dos.close();<br /> s.close();<br /> }<br /> } catch (IOException e) {<br /> e.printStackTrace();<br /> }<br /> }<br /> }<br />

UDP服务器端

package org.bruce.basic;</p> <p>import java.io.IOException;<br /> import java.net.DatagramPacket;<br /> import java.net.DatagramSocket;<br /> import java.net.SocketException;</p> <p>//UDP传输是一种无连接的数据传输方式，相较于TCP传输，它也是有它存在的道理的<br /> public class UDPServer {<br /> public static void main(String[] args) {</p> <p> //以 "字节数组" 的形式开辟一块内存用于缓存接收到的UDP数据包<br /> byte[] buffer = new byte[1024];</p> <p> //虽然开辟的缓冲内存大小为1024字节，但也可以设置一个小于该值的缓存空间接收数据包<br /> DatagramPacket dp = new DatagramPacket(buffer, buffer.length);<br /> DatagramSocket ds = null;<br /> try {<br /> //监听在UDP 9999 端口<br /> ds = new DatagramSocket(9999);<br /> } catch (SocketException e) {<br /> e.printStackTrace();<br /> }</p> <p> while(true) {<br /> try {<br /> //receive() 方法是一个阻塞性方法！<br /> ds.receive(dp);<br /> } catch (IOException e) {<br /> e.printStackTrace();<br /> }<br /> //从下一行代码中可以学习到一种用字节数组构造字符串对象的方法<br /> System.out.println(new String(buffer, 0, dp.getLength()));<br /> }<br /> }</p> <p>}<br />

UDP客户端

package org.bruce.basic;</p> <p>import java.io.IOException;<br /> import java.net.DatagramPacket;<br /> import java.net.DatagramSocket;<br /> import java.net.InetSocketAddress;<br /> import java.net.SocketException;</p> <p>public class UDPClient {</p> <p> public static void main(String[] args) {<br /> //先将 "Hello!" 封装成一个字符串对象，在调用其 getBytes() 方法将其转换成字节数组<br /> //转换成字节数组是为了方便传输<br /> byte[] buffer = (new String("Hello!")).getBytes();<br /> DatagramPacket dp = null;<br /> try {<br /> //将要发送的数据、要发送到什么地址设置好并打成一个 DatagramPacket 包<br /> dp = new DatagramPacket(buffer, buffer.length, new InetSocketAddress("127.0.0.1", 9999));<br /> } catch (SocketException e) {<br /> e.printStackTrace();<br /> }</p> <p> DatagramSocket ds = null;<br /> try {<br /> //new 一个DatagramSocket对象（即打开一个UDP端口准备从此处发出数据包）<br /> ds = new DatagramSocket(9998);<br /> ds.send(dp);<br /> ds.close();<br /> } catch (SocketException e) {<br /> e.printStackTrace();<br /> } catch (IOException e) {<br /> e.printStackTrace();<br /> }<br /> }</p> <p>}<br />