dubbo rpc rest

dubbo-rpc/dubbo-rpc-rest/src/main/java/com/alibaba/dubbo/rpc/protocol/rest/DubboHttpServer.java

@@ -36,11 +36,26 @@ import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 import java.util.Enumeration;
 
+/**
+ * 基于 `dubbo-remoting-http` 的 HTTP 服务器实现类
+ */
 public class DubboHttpServer extends BaseRestServer {
 
+    /**
+     * Resteasy HttpServletDispatcher
+     */
     private final HttpServletDispatcher dispatcher = new HttpServletDispatcher();
+    /**
+     * Resteasy ResteasyDeployment
+     */
     private final ResteasyDeployment deployment = new ResteasyDeployment();
+    /**
+     * Dubbo HttpBinder$Adaptive
+     */
     private HttpBinder httpBinder;
+    /**
+     * HttpServer 对象
+     */
     private HttpServer httpServer;
 //    private boolean isExternalServer;
 
@@ -48,10 +63,13 @@ public class DubboHttpServer extends BaseRestServer {
         this.httpBinder = httpBinder;
     }
 
+    @Override
     protected void doStart(URL url) {
+        // 创建 HttpServer 对象，使用 RestHandler 作为处理器。
         // TODO jetty will by default enable keepAlive so the xml config has no effect now
         httpServer = httpBinder.bind(url, new RestHandler());
 
+        // 获得 ServletContext 对象
         ServletContext servletContext = ServletManager.getInstance().getServletContext(url.getPort());
         if (servletContext == null) {
             servletContext = ServletManager.getInstance().getServletContext(ServletManager.EXTERNAL_SERVER_PORT);
@@ -60,9 +78,10 @@ public class DubboHttpServer extends BaseRestServer {
             throw new RpcException("No servlet context found. If you are using server='servlet', " +
                     "make sure that you've configured " + BootstrapListener.class.getName() + " in web.xml");
         }
+        // 设置 ResteasyDeployment
+        servletContext.setAttribute(ResteasyDeployment.class.getName(), deployment); // https://github.com/resteasy/Resteasy/blob/master/server-adapters/resteasy-undertow/src/main/java/org/jboss/resteasy/plugins/server/undertow/UndertowJaxrsServer.java#L74
 
-        servletContext.setAttribute(ResteasyDeployment.class.getName(), deployment);
-
+        // 初始化 Resteasy HttpServletDispatcher
         try {
             dispatcher.init(new SimpleServletConfig(servletContext));
         } catch (ServletException e) {
@@ -70,20 +89,26 @@ public class DubboHttpServer extends BaseRestServer {
         }
     }
 
+    @Override
     public void stop() {
         httpServer.close();
     }
 
+    @Override
     protected ResteasyDeployment getDeployment() {
         return deployment;
     }
 
     private class RestHandler implements HttpHandler {
 
+        @Override
         public void handle(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
+            // 设置
             RpcContext.getContext().setRemoteAddress(request.getRemoteAddr(), request.getRemotePort());
+            // 调度请求
             dispatcher.service(request, response);
         }
+
     }
 
     private static class SimpleServletConfig implements ServletConfig {
@@ -94,28 +119,38 @@ public class DubboHttpServer extends BaseRestServer {
             this.servletContext = servletContext;
         }
 
+        @Override
         public String getServletName() {
             return "DispatcherServlet";
         }
 
+        @Override
         public ServletContext getServletContext() {
             return servletContext;
         }
 
+        @Override
         public String getInitParameter(String s) {
             return null;
         }
 
+        @Override
         public Enumeration getInitParameterNames() {
             return new Enumeration() {
+
+                @Override
                 public boolean hasMoreElements() {
                     return false;
                 }
 
+                @Override
                 public Object nextElement() {
                     return null;
                 }
+
             };
         }
+
     }
+
 }

dubbo-rpc/dubbo-rpc-rest/src/main/java/com/alibaba/dubbo/rpc/protocol/rest/NettyServer.java

@@ -30,31 +30,38 @@ import java.util.Map;
 /**
  * Netty server can't support @Context injection of servlet objects since it's not a servlet container
  *
+ * 基于 Netty 的 HTTP 服务器实现类
  */
 public class NettyServer extends BaseRestServer {
 
     private final NettyJaxrsServer server = new NettyJaxrsServer();
 
+    @Override
     protected void doStart(URL url) {
+        // 设置 NettyJaxrsServer 的属性
         String bindIp = url.getParameter(Constants.BIND_IP_KEY, url.getHost());
         if (!url.isAnyHost() && NetUtils.isValidLocalHost(bindIp)) {
-            server.setHostname(bindIp);
+            server.setHostname(bindIp); // Hostname
         }
-        server.setPort(url.getParameter(Constants.BIND_PORT_KEY, url.getPort()));
+        server.setPort(url.getParameter(Constants.BIND_PORT_KEY, url.getPort())); // Port
         Map<ChannelOption, Object> channelOption = new HashMap<ChannelOption, Object>();
-        channelOption.put(ChannelOption.SO_KEEPALIVE, url.getParameter(Constants.KEEP_ALIVE_KEY, Constants.DEFAULT_KEEP_ALIVE));
+        channelOption.put(ChannelOption.SO_KEEPALIVE, url.getParameter(Constants.KEEP_ALIVE_KEY, Constants.DEFAULT_KEEP_ALIVE)); // Keep-Alive
         server.setChildChannelOptions(channelOption);
-        server.setExecutorThreadCount(url.getParameter(Constants.THREADS_KEY, Constants.DEFAULT_THREADS));
-        server.setIoWorkerCount(url.getParameter(Constants.IO_THREADS_KEY, Constants.DEFAULT_IO_THREADS));
-        server.setMaxRequestSize(url.getParameter(Constants.PAYLOAD_KEY, Constants.DEFAULT_PAYLOAD));
+        server.setExecutorThreadCount(url.getParameter(Constants.THREADS_KEY, Constants.DEFAULT_THREADS)); // 执行线程数
+        server.setIoWorkerCount(url.getParameter(Constants.IO_THREADS_KEY, Constants.DEFAULT_IO_THREADS)); // IO 线程数
+        server.setMaxRequestSize(url.getParameter(Constants.PAYLOAD_KEY, Constants.DEFAULT_PAYLOAD)); // 请求最大长度
+        // 启动 NettyJaxrsServer
         server.start();
     }
 
+    @Override
     public void stop() {
         server.stop();
     }
 
+    @Override
     protected ResteasyDeployment getDeployment() {
         return server.getDeployment();
     }
+
 }

dubbo-rpc/dubbo-rpc-rest/src/main/java/com/alibaba/dubbo/rpc/protocol/rest/RestServerFactory.java

@@ -33,7 +33,7 @@ public class RestServerFactory {
 
     public RestServer createServer(String name) {
         // TODO move names to Constants
-        if ("servlet".equalsIgnoreCase(name) || "jetty".equalsIgnoreCase(name) || "tomcat".equalsIgnoreCase(name)) {
+        if ("servlet".equalsIgnoreCase(name) || "jetty".equalsIgnoreCase(name) || "tomcat".equalsIgnoreCase(name)) { // `dubbo-remoting-http`
             return new DubboHttpServer(httpBinder);
         } else if ("netty".equalsIgnoreCase(name)) {
             return new NettyServer();
@@ -41,4 +41,5 @@ public class RestServerFactory {
             throw new IllegalArgumentException("Unrecognized server name: " + name);
         }
     }
+
 }