判断是否断开连接

src/main/java/com/jwk/spring/boot/rfid/RfidReaderUtil.java

@@ -32,6 +32,10 @@ public class RfidReaderUtil {
     public TagData[] readTags() {
         TagData[] readTags = null;
         try {
+            if (!reader.isConnected()) {
+                throw new Exception("连接已经断开！");
+            }
+
             // 清空标签
             reader.Actions.purgeTags();
 
@@ -42,9 +46,6 @@ public class RfidReaderUtil {
             reader.Actions.Inventory.stop();
 
             readTags = reader.Actions.getReadTags(properties.getNumberOfTags());
-            if (readTags == null) {
-                throw new Exception("读取标签为空！");
-            }
         } catch (Exception e) {
             log.error("RfidReader读取异常!", e);
             reader = new RFIDReader(properties.getHost(), properties.getPort(), properties.getTimeoutMilliseconds());