Update README.md

Author: Joezeo

README.md

@@ -3,3 +3,26 @@
 This project is a reactive web server template, using webflux + reactive-mongo as basic framework, a template for efficiently dealing with highly concurrent requests.  
 
 Servers bases on this template from my own have `7000+` throughput under `10000+` concurrency with `1s` response time in average via pressure test by Jmeter.
+
+### Usage
+The most important class was `com.toocol.common.web.AbstractHttpAction`, one HttpAction represent one http request handler, and add annotation `com.toocol.common.web.ActionMapping` to register http uri mapping. For example:  
+```java
+@Slf4j
+@AllArgsConstructor
+// uri is represent to "/article/add_article"
+@ActionMapping(module = "article", action = "add_article")
+public class AddArticleAction extends AbstractHttpAction<String> implements IVessel {
+
+    @Override
+    public Mono<String> action(JSONObject param) throws Exception {
+        ArticleAddress articleAddress = ArticleAddress.builder()
+                .digest(UUID.randomUUID().toString())
+                .url("https://www.guitarcs.article/1001")
+                .build();
+                
+        return vessel().articleAddressRepo.insert(articleAddress)
+                .thenReturn("Success");
+    }
+
+}
+```