meant to append

apm-sniffer/apm-sdk-plugin/spring-plugins/mvc-annotation-commons/src/main/java/org/apache/skywalking/apm/plugin/spring/mvc/commons/interceptor/RequestMappingMethodInterceptor.java

@@ -41,7 +41,7 @@ public class RequestMappingMethodInterceptor extends AbstractMethodInterceptor {
                     requestURL.append(",");
                 }
             }
-            requestURL = new StringBuilder("}");
+            requestURL.append("}");
         }
         if (methodRequestMapping.value().length > 0) {
             requestURL.append(methodRequestMapping.value()[0]);