Jetty 12: Cleanup StatisticsHandler (#9291)

#9145 cleanup statistics

Signed-off-by: Ludovic Orban <[email protected]>

documentation/jetty-documentation/src/main/asciidoc/old_docs/extras/statistics-handler.adoc

@@ -58,7 +58,7 @@ The following fragment shows how to configure a top level statistics handler:
 <Configure id="Server" class="org.eclipse.jetty.server.Server">
   <Call name="insertHandler">
     <Arg>
-      <New id="StatsHandler" class="org.eclipse.jetty.server.handler.StatisticsHandler"/>
+      <New id="StatisticsHandler" class="org.eclipse.jetty.server.handler.StatisticsHandler"/>
     </Arg>
   </Call>
 </Configure>

documentation/jetty-documentation/src/main/asciidoc/programming-guide/server/http/server-http-handler-use.adoc

@@ -243,7 +243,7 @@ Server applications can read these values and use them internally, or expose the
 
 [source,java,indent=0]
 ----
-include::../../{doc_code}/org/eclipse/jetty/docs/programming/server/http/HTTPServerDocs.java[tags=statsHandler]
+include::../../{doc_code}/org/eclipse/jetty/docs/programming/server/http/HTTPServerDocs.java[tags=statisticsHandler]
 ----
 
 The `Handler` tree structure looks like the following:
@@ -258,6 +258,14 @@ Server
         └── ContextHandler N
 ----
 
+It is possible to act on those statistics by subclassing `StatisticsHandler`.
+For instance, `StatisticsHandler.MinimumDataRateHandler` can be used to enforce a minimum read rate and a minimum write rate based of the figures collected by the `StatisticsHandler`:
+
+[source,java,indent=0]
+----
+include::../../{doc_code}/org/eclipse/jetty/docs/programming/server/http/HTTPServerDocs.java[tags=dataRateHandler]
+----
+
 [[pg-server-http-handler-use-util-secure-handler]]
 ====== SecuredRedirectHandler -- Redirect from HTTP to HTTPS
 

documentation/jetty-documentation/src/main/java/org/eclipse/jetty/docs/programming/server/http/HTTPServerDocs.java

@@ -927,9 +927,9 @@ public void rewriteHandler() throws Exception
         // end::rewriteHandler[]
     }
 
-    public void statsHandler() throws Exception
+    public void statisticsHandler() throws Exception
     {
-        // tag::statsHandler[]
+        // tag::statisticsHandler[]
         Server server = new Server();
         ServerConnector connector = new ServerConnector(server);
         server.addConnector(connector);
@@ -945,7 +945,29 @@ public void statsHandler() throws Exception
         statsHandler.setHandler(contextCollection);
 
         server.start();
-        // end::statsHandler[]
+        // end::statisticsHandler[]
+    }
+
+    public void dataRateHandler() throws Exception
+    {
+        // tag::dataRateHandler[]
+        Server server = new Server();
+        ServerConnector connector = new ServerConnector(server);
+        server.addConnector(connector);
+
+        // Create the MinimumDataRateHandler with a minimum read rate of 1KB per second and no minimum write rate.
+        StatisticsHandler.MinimumDataRateHandler dataRateHandler = new StatisticsHandler.MinimumDataRateHandler(1024L, 0L);
+
+        // Link the MinimumDataRateHandler to the Server.
+        server.setHandler(dataRateHandler);
+
+        // Create a ContextHandlerCollection to hold contexts.
+        ContextHandlerCollection contextCollection = new ContextHandlerCollection();
+        // Link the ContextHandlerCollection to the MinimumDataRateHandler.
+        dataRateHandler.setHandler(contextCollection);
+
+        server.start();
+        // end::dataRateHandler[]
     }
 
     public void securedHandler() throws Exception

jetty-core/jetty-server/src/main/config/etc/jetty-stats.xml → jetty-core/jetty-server/src/main/config/etc/jetty-statistics.xml

@@ -6,13 +6,13 @@
 <!-- =============================================================== -->
 
 <Configure id="Server" class="org.eclipse.jetty.server.Server">
+  <!-- Collects request stats -->
   <Call name="insertHandler">
     <Arg>
-      <New id="StatsHandler" class="org.eclipse.jetty.server.handler.StatisticsHandler">
-        <Set name="gracefulShutdownWaitsForRequests"><Property name="jetty.statistics.gracefulShutdownWaitsForRequests" default="true"/></Set>
-      </New>
+      <New id="StatisticsHandler" class="org.eclipse.jetty.server.handler.StatisticsHandler"/>
     </Arg>
   </Call>
+  <!-- Collects connection stats -->
   <Call name="addBeanToAllConnectors">
     <Arg>
       <New class="org.eclipse.jetty.io.ConnectionStatistics"/>

jetty-core/jetty-server/src/main/config/modules/statistics.mod

@@ -0,0 +1,13 @@
+# DO NOT EDIT - See: https://www.eclipse.org/jetty/documentation/current/startup-modules.html
+
+[description]
+Enables statistics collection for the server.
+
+[tags]
+server
+
+[depend]
+server
+
+[xml]
+etc/jetty-statistics.xml