diff --git a/dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AbstractInvoker.java b/dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AbstractInvoker.java
index d59af2b4502..4cd91486b7b 100644
--- a/dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AbstractInvoker.java
+++ b/dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AbstractInvoker.java
@@ -134,11 +134,11 @@ public Result invoke(Invocation inv) throws RpcException {
         }
         RpcInvocation invocation = (RpcInvocation) inv;
         invocation.setInvoker(this);
-        if (attachment != null && attachment.size() > 0) {
+        if (attachment != null && !attachment.isEmpty()) {
             invocation.addAttachmentsIfAbsent(attachment);
         }
         Map<String, String> contextAttachments = RpcContext.getContext().getAttachments();
-        if (contextAttachments != null && contextAttachments.size() != 0) {
+        if (contextAttachments != null && !contextAttachments.isEmpty()) {
             /**
              * invocation.addAttachmentsIfAbsent(context){@link RpcInvocation#addAttachmentsIfAbsent(Map)}should not be used here,
              * because the {@link RpcContext#setAttachment(String, String)} is passed in the Filter when the call is triggered