java socket网络编程

tcp网络编程

//客户端
public class TCPClient {
public static void main(String[] args) throws Exception {
Socket s = new Socket("127.0.0.1", 6666); //指定主机的指定端口
OutputStream os = s.getOutputStream();  //拿到输出流
DataOutputStream dos = new DataOutputStream(os);
Thread.sleep(30000);
dos.writeUTF("你好！");
dos.flush();
dos.close();
s.close();
}
}

//服务端
public class TCPServer {
public static void main(String[] args) throws Exception {
ServerSocket ss = new ServerSocket(6666); //监听6666端口
while(true) {
Socket s = ss.accept();  //侦听并接受到此套接字的连接
DataInputStream dis = new DataInputStream(s.getInputStream());
System.out.println(dis.readUTF());  //你好!
dis.close();
s.close();
}
}
}

//客户端
public class TestClient {
public static void main(String[] args) throws Exception {
try {
Socket s = new Socket("127.0.0.1", 8888); //指定主机的指定端口
InputStream is = s.getInputStream();  //拿到输出流
DataInputStream dis = new DataInputStream(is);
System.out.println(dis.readUTF());  //Hello /127.0.0.1 port 56637 bye bye!
dis.close();
s.close();
}catch (ConnectException connExc) {
connExc.printStackTrace();
System.err.println("服务器连接失败");
}catch (IOException e) {
e.printStackTrace();
}
}
}

//服务端
public class TestServer {
public static void main(String[] args) throws Exception {
try {
ServerSocket ss = new ServerSocket(8888); //监听6666端口
while(true) {
Socket s = ss.accept();  //侦听并接受到此套接字的连接
DataOutputStream dos = new DataOutputStream(s.getOutputStream());
//得到客户端的IP和端口号
dos.writeUTF("Hello " + s.getInetAddress() + " port " + s.getPort()+" bye bye!");
dos.flush();
dos.close();
s.close();
}
}catch (IOException e) {
e.printStackTrace();
System.out.println("程序运行出错"+e);
}
}
}

//客户端
public class TestSocketClient {
public static void main(String[] args) throws Exception {
InputStream in = null;
OutputStream out = null;
try {
Socket socket = new Socket("127.0.0.1", 5888);
in = socket.getInputStream();
out = socket.getOutputStream();
DataInputStream dis = new DataInputStream(in);
DataOutputStream dos = new DataOutputStream(out);
dos.writeUTF("hello, server!");
String s = null;
if((s = dis.readUTF()) != null) {
System.out.println(s);  //hello,client!
}
dos.close();
dis.close();
socket.close();
}catch(UnknownHostException e) {
e.printStackTrace();
}catch (IOException e) {
e.printStackTrace();
}
}
}

//服务端
public class TestSocketServer {
public static void main(String[] args) throws Exception {
InputStream in = null;
OutputStream out = null;
try {
ServerSocket ss = new ServerSocket(5888);
Socket socket = ss.accept();
in = socket.getInputStream();
out = socket.getOutputStream();
DataInputStream dis = new DataInputStream(in);
DataOutputStream dos = new DataOutputStream(out);
String s = null;
if((s = dis.readUTF()) != null) {
System.out.println(s);  //hello, server!
System.out.println("from " + sock
4000
et.getInetAddress());  //from /127.0.0.1
System.out.println("port " + socket.getPort());  //port 56759
}
dos.writeUTF("hello,client!");
dis.close();
dos.close();
socket.close();
}catch(IOException e) {
e.printStackTrace();
}
}
}

//客户端
public class ChatClient {
public static void main(String[] args) {
InputStream in = null;
OutputStream out = null;
InputStreamReader isr= null;
PrintWriter pw = null;
BufferedReader br = null;
BufferedWriter bw = null;
Socket client;
try {
client = new Socket("127.0.0.1", 9999);
in = client.getInputStream();
out = client.getOutputStream();
isr = new InputStreamReader(in);
pw = new PrintWriter(out);
br = new BufferedReader(isr);
BufferedReader sin = new BufferedReader(new InputStreamReader(System.in));
String line;
line = sin.readLine();
while(!line.equals("goodbye")) {
pw.println(line);
pw.flush();
System.out.println("client send:" + line);
System.out.println("client receive:" + br.readLine());
line = sin.readLine();
}
pw.close();
br.close();
client.close();
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}

//服务端
public class ChatServer {
public static void main(String[] args) {
InputStream in = null;
OutputStream out = null;
InputStreamReader isr = null;
PrintWriter pw = null;
BufferedReader br = null;
try {
ServerSocket serverSocket = new ServerSocket(9999);
Socket server = serverSocket.accept();
String line;
in = server.getInputStream();
out = server.getOutputStream();
isr = new InputStreamReader(in);
pw = new PrintWriter(out);
br = new BufferedReader(isr);
BufferedReader sin = new BufferedReader(new InputStreamReader(
System.in));
System.out.println("server receive:" + br.readLine());
line = sin.readLine();
while (!line.equals("goodbye")) {
pw.println(line);
pw.flush();
System.out.println("server send:" + line);
System.out.println("server receive:" + br.readLine());
line = sin.readLine();
}
pw.close();
br.close();
server.close();
serverSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

udp网络编程

//udp客户端
public class TestUDPClient {
public static void main(String[] args) throws Exception {
long n = 10000L;
ByteArrayOutputStream baos = new ByteArrayOutputStream();
DataOutputStream dos = new DataOutputStream(baos);
dos.writeLong(n);
byte[] buf = baos.toByteArray();
//byte[] buf = new String("hello").getBytes();
DatagramPacket dp = new DatagramPacket(buf, buf.length, new InetSocketAddress("127.0.0.1", 5678));
DatagramSocket ds = new DatagramSocket(9999);
ds.send(dp);
ds.close();
}
}

//udp服务器端
public class TestUDPServer {
public static void main(String[] args) throws Exception {
byte[] buf = new byte[1024];  //接收客户端数据
DatagramPacket dp = new DatagramPacket(buf, buf.length);  //数据包
DatagramSocket ds = new DatagramSocket(5678);   //监听udp的5678端口,tcp还有一个5678端口
while(true) {
ds.receive(dp);
ByteArrayInputStream bais = new ByteArrayInputStream(buf);
DataInputStream dis = new DataInputStream(bais);
System.out.println(dis.readLong());  //10000
}
}
}