simplify map empty judgment (#3376)

zonghaishang · web-flow · commit 7f262f960b83 · 2019-01-29T13:38:51.000+08:00
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
@@ -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

Original file line number	Diff line number	Diff line change
`@@ -134,11 +134,11 @@ public Result invoke(Invocation inv) throws RpcException {`
`134`	`134`	`}`
`135`	`135`	`RpcInvocation invocation = (RpcInvocation) inv;`
`136`	`136`	`invocation.setInvoker(this);`
`137`		`- if (attachment != null && attachment.size() > 0) {`
	`137`	`+ if (attachment != null && !attachment.isEmpty()) {`
`138`	`138`	`invocation.addAttachmentsIfAbsent(attachment);`
`139`	`139`	`}`
`140`	`140`	`Map<String, String> contextAttachments = RpcContext.getContext().getAttachments();`
`141`		`- if (contextAttachments != null && contextAttachments.size() != 0) {`
	`141`	`+ if (contextAttachments != null && !contextAttachments.isEmpty()) {`
`142`	`142`	`/**`
`143`	`143`	`* invocation.addAttachmentsIfAbsent(context){@link RpcInvocation#addAttachmentsIfAbsent(Map)}should not be used here,`
`144`	`144`	`* because the {@link RpcContext#setAttachment(String, String)} is passed in the Filter when the call is triggered`