Issue #3341 - change HttpClientProvider to interface

- HttpClientProvider is now an interface which defines a default method
newHttpClient, its static get() method get will attempt to use the
XmlHttpClientProvider to create a client, and if this fails to give a
non null client it will be created with the default newHttpClient method

Signed-off-by: Lachlan Roberts <lachlan@webtide.com>

jetty-websocket/jetty-websocket-client/src/main/java/module-info.java

@@ -27,7 +27,4 @@ module org.eclipse.jetty.websocket.jetty.client
     requires org.eclipse.jetty.websocket.jetty.api;
     requires org.eclipse.jetty.websocket.core;
     requires org.eclipse.jetty.websocket.jetty.common;
-
-    // Only required if using XmlBasedHttpClientProvider.
-    requires static org.eclipse.jetty.xml;
 }

jetty-websocket/jetty-websocket-client/src/test/java/org/eclipse/jetty/websocket/client/HttpClientInitTest.java

@@ -46,7 +46,7 @@ public class HttpClientInitTest
             assertThat("Executor exists", executor, notNullValue());
             assertThat("Executor instanceof", executor, instanceOf(QueuedThreadPool.class));
             QueuedThreadPool threadPool = (QueuedThreadPool)executor;
-            assertThat("QueuedThreadPool.name", threadPool.getName(), startsWith("Jetty-WebSocketClient@"));
+            assertThat("QueuedThreadPool.name", threadPool.getName(), startsWith("WebSocketClient@"));
         }
         finally
         {

jetty-websocket/websocket-core/src/main/java/module-info.java

@@ -37,9 +37,11 @@ module org.eclipse.jetty.websocket.core
     requires org.eclipse.jetty.io;
     requires org.eclipse.jetty.http;
     requires org.eclipse.jetty.server;
-    requires static org.eclipse.jetty.xml;
     requires org.eclipse.jetty.util;
 
+    // Only required if using XmlBasedHttpClientProvider.
+    requires static org.eclipse.jetty.xml;
+
     uses Extension;
 
     provides Extension with

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/client/DefaultHttpClientProvider.java

@@ -1,39 +0,0 @@
-//
-//  ========================================================================
-//  Copyright (c) 1995-2019 Mort Bay Consulting Pty. Ltd.
-//  ------------------------------------------------------------------------
-//  All rights reserved. This program and the accompanying materials
-//  are made available under the terms of the Eclipse Public License v1.0
-//  and Apache License v2.0 which accompanies this distribution.
-//
-//      The Eclipse Public License is available at
-//      http://www.eclipse.org/legal/epl-v10.html
-//
-//      The Apache License v2.0 is available at
-//      http://www.opensource.org/licenses/apache2.0.php
-//
-//  You may elect to redistribute this code under either of these licenses.
-//  ========================================================================
-//
-
-package org.eclipse.jetty.websocket.core.client;
-
-import org.eclipse.jetty.client.HttpClient;
-import org.eclipse.jetty.util.ssl.SslContextFactory;
-import org.eclipse.jetty.util.thread.QueuedThreadPool;
-
-class DefaultHttpClientProvider
-{
-    public static HttpClient newHttpClient()
-    {
-        HttpClient client = new HttpClient(new SslContextFactory());
-        client.getSslContextFactory().setEndpointIdentificationAlgorithm("HTTPS");
-
-        QueuedThreadPool threadPool = new QueuedThreadPool();
-        threadPool.setName("WebSocketClient@" + client.hashCode());
-        threadPool.setDaemon(true);
-        client.setExecutor(threadPool);
-
-        return client;
-    }
-}

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/client/HttpClientProvider.java

@@ -18,33 +18,36 @@
 
 package org.eclipse.jetty.websocket.core.client;
 
-import java.lang.reflect.Method;
-
 import org.eclipse.jetty.client.HttpClient;
 import org.eclipse.jetty.util.log.Log;
+import org.eclipse.jetty.util.ssl.SslContextFactory;
+import org.eclipse.jetty.util.thread.QueuedThreadPool;
 
-public final class HttpClientProvider
+public interface HttpClientProvider
 {
-    public static HttpClient get()
+    static HttpClient get()
     {
         try
         {
-            if (Class.forName("org.eclipse.jetty.xml.XmlConfiguration") != null)
-            {
-                Class<?> xmlClazz = Class.forName("org.eclipse.jetty.websocket.core.client.XmlBasedHttpClientProvider");
-                Method getMethod = xmlClazz.getMethod("get");
-                Object ret = getMethod.invoke(null);
-                if ((ret != null) && (ret instanceof HttpClient))
-                {
-                    return (HttpClient)ret;
-                }
-            }
+            HttpClientProvider xmlProvider = new XmlHttpClientProvider();
+            HttpClient client = xmlProvider.newHttpClient();
+            if (client != null)
+                return client;
         }
         catch (Throwable ignore)
         {
             Log.getLogger(HttpClientProvider.class).ignore(ignore);
         }
 
-        return DefaultHttpClientProvider.newHttpClient();
+        return new HttpClientProvider(){}.newHttpClient();
+    }
+
+    default HttpClient newHttpClient()
+    {
+        HttpClient client = new HttpClient(new SslContextFactory());
+        QueuedThreadPool threadPool = new QueuedThreadPool();
+        threadPool.setName("WebSocketClient@" + client.hashCode());
+        client.setExecutor(threadPool);
+        return client;
     }
 }

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/client/WebSocketCoreClient.java

@@ -20,6 +20,7 @@ package org.eclipse.jetty.websocket.core.client;
 
 import java.io.IOException;
 import java.net.URI;
+import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 
 import org.eclipse.jetty.client.HttpClient;
@@ -61,7 +62,7 @@ public class WebSocketCoreClient extends ContainerLifeCycle implements FrameHand
     public WebSocketCoreClient(HttpClient httpClient, FrameHandler.Customizer customizer)
     {
         if (httpClient == null)
-            httpClient = HttpClientProvider.get();
+            httpClient = Objects.requireNonNull(HttpClientProvider.get());
 
         this.httpClient = httpClient;
         this.extensionRegistry = new WebSocketExtensionRegistry();

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/core/client/XmlHttpClientProvider.java

@@ -25,9 +25,10 @@ import org.eclipse.jetty.client.HttpClient;
 import org.eclipse.jetty.util.log.Log;
 import org.eclipse.jetty.xml.XmlConfiguration;
 
-class XmlBasedHttpClientProvider
+class XmlHttpClientProvider implements HttpClientProvider
 {
-    public static HttpClient get()
+    @Override
+    public HttpClient newHttpClient()
     {
         URL resource = Thread.currentThread().getContextClassLoader().getResource("jetty-websocket-httpclient.xml");
         if (resource == null)
@@ -42,7 +43,7 @@ class XmlBasedHttpClientProvider
         }
         catch (Throwable t)
         {
-            Log.getLogger(XmlBasedHttpClientProvider.class).warn("Unable to load: " + resource, t);
+            Log.getLogger(XmlHttpClientProvider.class).warn("Unable to load: " + resource, t);
         }
 
         return null;