修改重连逻辑

src/main/java/com/example/lxcameraapi/service/s7/S7MultiPlcService.java

@@ -109,6 +109,12 @@ public class S7MultiPlcService {
     // 读取间隔(ms)
     private static final int READ_INTERVAL = 1000;
 
+    // 重连最大重试次数
+    private static final int RECONNECT_MAX_RETRIES = 5;
+
+    // 重连间隔(ms)
+    private static final int RECONNECT_INTERVAL = 3000;
+
     // 线程池
     private ExecutorService executorService;
 
@@ -189,10 +195,16 @@ public class S7MultiPlcService {
         try {
             S7Client client = pool.take();
             if (!client.Connected) {
-                PlcData config = getPlcConfig(plcNumber);
-                if (config != null) {
-                    client.ConnectTo(config.getIp(), config.getRack(), config.getSlot());
+                client.Disconnect();
+                // 用带重试的方法重新连接
+                S7Client newClient = reconnectWithRetry(plcNumber);
+                if (newClient != null) {
+                    return newClient;
                 }
+                // 重连失败，把旧client放回（虽然不可用，至少不丢失池容量）
+                log.warn("PLC {} 获取连接时重连失败", plcNumber);
+                pool.offer(client);
+                return null;
             }
             return client;
         } catch (InterruptedException e) {
@@ -211,16 +223,45 @@ public class S7MultiPlcService {
             if (client.Connected) {
                 pool.offer(client);
             } else {
+                // 断开旧连接，尝试重连后放回池中
+                client.Disconnect();
+                S7Client newClient = reconnectWithRetry(plcNumber);
+                if (newClient != null) {
+                    pool.offer(newClient);
+                } else {
+                    log.warn("PLC {} 归还连接时重连失败，池中剩余: {}/{}", plcNumber, pool.size(), POOL_SIZE);
+                }
+            }
+        }
+    }
+
+    /**
+     * 带重试的重连，尝试多次直到成功或达到上限
+     * @return 新连接，失败返回null
+     */
+    private S7Client reconnectWithRetry(String plcNumber) {
         PlcData config = getPlcConfig(plcNumber);
-                if (config != null) {
+        if (config == null) return null;
+
+        for (int i = 1; i <= RECONNECT_MAX_RETRIES; i++) {
             S7Client newClient = new S7Client();
             int result = newClient.ConnectTo(config.getIp(), config.getRack(), config.getSlot());
             if (result == 0) {
-                        pool.offer(newClient);
+                log.info("PLC {} 重连成功（第{}次尝试）", plcNumber, i);
+                return newClient;
             }
+            log.warn("PLC {} 重连失败（第{}/{}次），错误码: {}", plcNumber, i, RECONNECT_MAX_RETRIES, result);
+            if (i < RECONNECT_MAX_RETRIES) {
+                try {
+                    sleep(RECONNECT_INTERVAL);
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                    break;
                 }
             }
         }
+        log.error("PLC {} 重连失败，已达最大重试次数 {}", plcNumber, RECONNECT_MAX_RETRIES);
+        return null;
     }
 
     /**
@@ -313,9 +354,31 @@ public class S7MultiPlcService {
 
             if (result != 0) {
                 log.error("PLC {} 读取失败，错误码: {}", plcNumber, result);
+                // 断开坏连接，防止僵尸连接被复用
+                client.Disconnect();
                 returnConnection(plcNumber, client);
+                // 重试一次
+                S7Client retryClient = getConnection(plcNumber);
+                if (retryClient != null) {
+                    try {
+                        byte[] retryBuffer = new byte[readLength];
+                        int retryResult = retryClient.ReadArea(S7.S7AreaDB, config.getReadDataBlock(), 0, readLength, retryBuffer);
+                        if (retryResult == 0) {
+                            log.info("PLC {} 重试读取成功", plcNumber);
+                            buffer = retryBuffer;
+                            result = 0;
+                        } else {
+                            log.error("PLC {} 重试读取仍失败，错误码: {}", plcNumber, retryResult);
+                            retryClient.Disconnect();
+                        }
+                    } finally {
+                        returnConnection(plcNumber, retryClient);
+                    }
+                }
+                if (result != 0) {
                     return readDataCache.get(plcNumber);
                 }
+            }
 
             PlcReadData data = new PlcReadData();
             data.setPalletNo(readString(buffer, (int) config.getPalletOffset(), getDataTypeSize(config.getPalletDataType())));
@@ -648,6 +711,8 @@ public class S7MultiPlcService {
                 log.info("PLC {} 写入拍照结果成功: {}", plcNumber, photoResult);
             } else {
                 log.error("PLC {} 写入拍照结果失败，错误码: {}", plcNumber, result);
+                // 断开坏连接，防止僵尸连接被复用
+                client.Disconnect();
             }
             returnConnection(plcNumber, client);
             return result == 0;
@@ -704,6 +769,7 @@ public class S7MultiPlcService {
             List<S7Client> clients = new ArrayList<>();
             pool.drainTo(clients);
 
+            // 1. 保留有效连接，清理无效连接
             for (S7Client client : clients) {
                 if (client != null && client.Connected) {
                     pool.offer(client);
@@ -711,20 +777,25 @@ public class S7MultiPlcService {
                     if (client != null) {
                         client.Disconnect();
                     }
-                    PlcData config = getPlcConfig(plcNumber);
-                    if (config != null) {
-                        S7Client newClient = new S7Client();
-                        int result = newClient.ConnectTo(config.getIp(), config.getRack(), config.getSlot());
-                        if (result == 0) {
-                            pool.offer(newClient);
                     cleaned++;
                 }
             }
+
+            // 2. 补满连接池到POOL_SIZE（带重试）
+            int currentSize = pool.size();
+            for (int i = currentSize; i < POOL_SIZE; i++) {
+                log.info("PLC {} 连接池不足({}/{})，尝试补充...", plcNumber, currentSize, POOL_SIZE);
+                S7Client newClient = reconnectWithRetry(plcNumber);
+                if (newClient != null) {
+                    pool.offer(newClient);
+                } else {
+                    log.error("PLC {} 补充连接失败，当前池大小: {}/{}", plcNumber, pool.size(), POOL_SIZE);
+                    break; // 重试都失败了，不再继续补
                 }
             }
 
-            if (cleaned > 0) {
-                log.info("PLC {} 替换了 {} 个无效连接", plcNumber, cleaned);
+            if (cleaned > 0 || pool.size() < POOL_SIZE) {
+                log.info("PLC {} 清理{}个无效连接，当前池大小: {}/{}", plcNumber, cleaned, pool.size(), POOL_SIZE);
             }
         }
         log.info("PLC连接池清理完成");