AJ-862: fix issue about single node reconnect nums;

Author: chengyitian

src/com/xxdb/DBConnection.java

@@ -1296,19 +1296,19 @@ public void switchDataNode(Node node) throws IOException{
                     isConnected = true;
                     break;
                 }
-            }
-
-            if (nodes_.isEmpty()){
-                log.error("Connect to " + node.hostName + ":" + node.port + " failed.");
-                throw new RuntimeException("Connect to " + node.hostName + ":" + node.port + " failed.");
-            }
+            } else {
+                if (nodes_.isEmpty()){
+                    log.error("Connect to " + node.hostName + ":" + node.port + " failed.");
+                    throw new RuntimeException("Connect to " + node.hostName + ":" + node.port + " failed.");
+                }
 
-            int index = nodeRandom_.nextInt(nodes_.size());
-            if (connectNode(nodes_.get(index))) {
-                if (nodes_.size() > 1)
-                    log.info("Switch to node: " + nodes_.get(index).hostName + ":" + nodes_.get(index).port + " successfully.");
-                isConnected = true;
-                break;
+                int index = nodeRandom_.nextInt(nodes_.size());
+                if (connectNode(nodes_.get(index))) {
+                    if (nodes_.size() > 1)
+                        log.info("Switch to node: " + nodes_.get(index).hostName + ":" + nodes_.get(index).port + " successfully.");
+                    isConnected = true;
+                    break;
+                }
             }
 
             try {