![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/04\/20250418193306-6802a8f2b4ce2.png\")
<\/p>\n\u4ee5\u4e0b\u4ee3\u7801\u663e\u793a\u4e86\u5982\u4f55\u7f16\u5199UDP\u56de\u663e\u670d\u52a1\u5668：<\/p>\n
DatagramSocket socket = new DatagramSocket(12345);
\nDatagramPacket packet = new DatagramPacket(new byte[1024], 1024);
\nwhile(true) {
\n \/\/ Receive the packet socket.
\n receive(packet);<\/p>\n
\/\/Send back the same packet to the sender socket.
\n send(packet);
\n}<\/p>\n
\u57fa\u4e8eUDP\u5957\u63a5\u5b57\u7684Echo\u670d\u52a1\u5668<\/p>\n
import java.net.DatagramPacket;
\nimport java.net.DatagramSocket;
\nimport java.net.InetAddress;<\/p>\n
public class Main {
\n public static void main(String[] args) throws Exception {
\n final int LOCAL_PORT = 12345;
\n final String SERVER_NAME = "localhost";
\n DatagramSocket udpSocket = new DatagramSocket(LOCAL_PORT,
\n InetAddress.getByName(SERVER_NAME));<\/p>\n
System.out.println("Created UDP server socket at "
\n + udpSocket.getLocalSocketAddress() + "…");
\n while (true) {
\n System.out.println("Waiting for a UDP packet…");
\n DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);
\n udpSocket.receive(packet);
\n displayPacketDetails(packet);
\n udpSocket.send(packet);
\n }
\n }
\n public static void displayPacketDetails(DatagramPacket packet) {
\n byte[] msgBuffer = packet.getData();
\n int length = packet.getLength();
\n int offset = packet.getOffset();<\/p>\n
int remotePort = packet.getPort();
\n InetAddress remoteAddr = packet.getAddress();
\n String msg = new String(msgBuffer, offset, length);<\/p>\n
System.out.println("Received a packet:[IP Address=" + remoteAddr
\n + ", port=" + remotePort + ", message=" + msg + "]");
\n }
\n}<\/p>\n
\u4e0a\u9762\u7684\u4ee3\u7801\u751f\u6210\u4ee5\u4e0b\u7ed3\u679c\u3002<\/p>\n<\/p>\n
<\/p>\n
\u57fa\u4e8eUDP\u5957\u63a5\u5b57\u7684Echo\u5ba2\u6237\u7aef<\/p>\n
import java.io.BufferedReader;
\nimport java.io.InputStreamReader;
\nimport java.net.DatagramPacket;
\nimport java.net.DatagramSocket;
\nimport java.net.InetAddress;
\nimport java.net.UnknownHostException;<\/p>\n
public class Main {
\n public static void main(String[] args) throws Exception {
\n DatagramSocket udpSocket = new DatagramSocket();
\n String msg = null;
\n BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
\n System.out.print("Please enter a message (Bye to quit):");
\n while ((msg = br.readLine()) != null) {
\n if (msg.equalsIgnoreCase("bye")) {
\n break;
\n }
\n DatagramPacket packet = Main.getPacket(msg);
\n udpSocket.send(packet);
\n udpSocket.receive(packet);
\n displayPacketDetails(packet);
\n System.out.print("Please enter a message (Bye to quit):");
\n }
\n udpSocket.close();
\n }
\n public static void displayPacketDetails(DatagramPacket packet) {
\n byte[] msgBuffer = packet.getData();
\n int length = packet.getLength();
\n int offset = packet.getOffset();
\n int remotePort = packet.getPort();
\n InetAddress remoteAddr = packet.getAddress();
\n String msg = new String(msgBuffer, offset, length);
\n System.out.println("[Server at IP Address=" + remoteAddr + ", port="
\n + remotePort + "]: " + msg);
\n }
\n public static DatagramPacket getPacket(String msg)
\n throws UnknownHostException {
\n int PACKET_MAX_LENGTH = 1024;
\n byte[] msgBuffer = msg.getBytes();<\/p>\n
int length = msgBuffer.length;
\n if (length > PACKET_MAX_LENGTH) {
\n length = PACKET_MAX_LENGTH;
\n }
\n DatagramPacket packet = new DatagramPacket(msgBuffer, length);
\n InetAddress serverIPAddress = InetAddress.getByName("localhost");
\n packet.setAddress(serverIPAddress);
\n packet.setPort(15900);
\n return packet;
\n }
\n}<\/p>\n
\u4e0a\u9762\u7684\u4ee3\u7801\u751f\u6210\u4ee5\u4e0b\u7ed3\u679c\u3002<\/p>\n<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/04\/20250418193306-6802a8f2cd388.png\")
<\/p>\n","protected":false},"excerpt":{"rendered":"
\u6587\u7ae0\u6d4f\u89c8\u9605\u8bfb929\u6b21\uff0c\u70b9\u8d5e22\u6b21\uff0c\u6536\u85cf5\u6b21\u3002\u7b2c\u4e09\u767e\u4e09\u5341\u8282 Java\u7f51\u7edc\u6559\u7a0b – Java\u7f51\u7edcUDP\u670d\u52a1\u5668<\/p>\n","protected":false},"author":2,"featured_media":20633,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[99,1611,193,586,190,78,191],"topic":[],"class_list":{"0":"post-20635","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","6":"hentry","7":"category-server","8":"tag-java","10":"tag-udp","11":"tag-586","12":"tag-190","13":"tag-78","14":"tag-191"},"yoast_head":"\n