餐盘柜优化

2026-01-16 11:53:44 +08:00
parent ab58651733
commit 8337b3fabb
19 changed files with 1099 additions and 110 deletions
@@ -0,0 +1,47 @@
+package com.sw.platecabinet.socket;
+
+import java.net.DatagramPacket;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+
+/**
+ * Simple UDP discovery client:
+ * Sends "DISCOVER_SERVER" broadcast and waits for first reply "SERVER_FOUND:serverName:ip"
+ */
+public class UdpDiscoveryClient {
+
+    public interface Listener {
+        void onFound(String ip, String serverName);
+
+        void onError(Exception e);
+    }
+
+    public void discover(int discoveryPort, int timeoutMs, Listener listener) {
+        new Thread(() -> {
+            try (DatagramSocket socket = new DatagramSocket()) {
+                socket.setBroadcast(true);
+                byte[] data = "DISCOVER_SERVER".getBytes();
+                DatagramPacket packet = new DatagramPacket(data, data.length, InetAddress.getByName("255.255.255.255"), discoveryPort);
+                socket.send(packet);
+
+                socket.setSoTimeout(timeoutMs);
+                byte[] buf = new byte[512];
+                DatagramPacket resp = new DatagramPacket(buf, buf.length);
+                socket.receive(resp);
+
+                String msg = new String(resp.getData(), 0, resp.getLength());
+                if (msg.startsWith("SERVER_FOUND")) {
+                    // format: SERVER_FOUND:serverName:ip
+                    String[] parts = msg.split(":", 3);
+                    if (parts.length >= 3) {
+                        listener.onFound(parts[2], parts[1]);
+                        return;
+                    }
+                }
+                listener.onError(new Exception("Invalid response"));
+            } catch (Exception e) {
+                listener.onError(e);
+            }
+        }).start();
+    }
+}