11 Remove direct support for QuickStart and document it in README.md …

…instead. Fixes #11

README.md

@@ -695,6 +695,67 @@ Many more example projects:
 If you like [Kotlin](https://kotlinlang.org/) and you like the simplicity of the ideas above,
 please use the [Vaadin-on-Kotlin](https://www.vaadinonkotlin.eu/) framework which is based on the ideas above.
 
+## Advanced Use-Cases
+
+### Jetty QuickStart
+
+Jetty can optionally start faster if we don't classpath-scan for resources, and instead pass in a QuickStart XML file with all resources listed.
+This is mandatory for native mode, since classpath scanning doesn't work in native mode.
+
+See [Jetty QuickStart Documentation](https://www.eclipse.org/jetty/documentation/jetty-12/operations-guide/index.html#og-quickstart)
+for more details; see [Jetty Maven plugin](https://www.eclipse.org/jetty/documentation/jetty-12/programming-guide/index.html#jetty-effective-web-xml-goal)
+documentation as well on how to generate the QuickStart configuration file.
+Also see [Issue #11](https://github.com/mvysny/vaadin-boot/issues/11).
+
+To enable QuickStart mode, add a dependency on Jetty QuickStart: `org.eclipse.jetty:jetty-quickstart:11.0.14`.
+
+The quickstart configuration lists e.g. a list of Vaadin Routes, and therefore
+it's good to generate it during compile time. Unfortunately, at the moment, Maven Jetty plugin can't
+do that, see&vote for [Jetty #9497](https://github.com/eclipse/jetty.project/issues/9497). 
+
+Workaround is to generate the config file manually. You need to start your app in order for Jetty to
+perform the classpath scanning. Don't forget to run the app in production mode, otherwise
+the quickstart config file will contain Vaadin dev mode stuff like `DevModeStartupListener`.
+
+```java
+public class Main {
+    public static void main(String[] args) throws Exception {
+        new VaadinBoot() {
+            protected void onStarted(@NotNull WebAppContext context) {
+                context.setAttribute(ExtraXmlDescriptorProcessor.class.getName(), new ExtraXmlDescriptorProcessor());
+                final String xml = new File("quickstart-web.xml").getAbsolutePath();
+                try (OutputStream out = new BufferedOutputStream(new FileOutputStream(xml))) {
+                    new QuickStartGeneratorConfiguration().generateQuickStartWebXml(context, out);
+                }
+            }
+        }.withArgs(args).run();
+    }
+}
+```
+
+Place the file here: `src/main/resources/webapp/WEB-INF/quickstart-web.xml`. From now on,
+Jetty should read the QuickStart config and skip the classpath scanning automatically; however
+you can still enforce the QuickStart mode:
+
+```java
+public class Main {
+    public static void main(String[] args) throws Exception {
+        new VaadinBoot() {
+            protected WebAppContext createWebAppContext() throws MalformedURLException {
+                WebAppContext ctx = super.createWebAppContext();
+                context.setAttribute(QuickStartConfiguration.MODE, QuickStartConfiguration.Mode.QUICKSTART);
+                return ctx;
+            }
+        }.withArgs(args).disableClasspathScanning().run();
+    }
+}
+```
+
+## Native
+
+Building a native app with GraalVM is unsupported at the moment. Please see [Issue #10](https://github.com/mvysny/vaadin-boot/issues/10)
+for more details.
+
 # Developing Vaadin-Boot
 
 See [CONTRIBUTING](CONTRIBUTING.md)

vaadin-boot/src/main/java/com/github/mvysny/vaadinboot/VaadinBoot.java

@@ -12,7 +12,6 @@
 import javax.servlet.Servlet;
 import java.io.IOException;
 import java.net.InetSocketAddress;
-import java.net.MalformedURLException;
 import java.time.Duration;
 import java.util.Objects;
 
@@ -64,6 +63,14 @@ public class VaadinBoot {
      */
     private boolean openBrowserInDevMode = true;
 
+    /**
+     * If true, no classpath scanning is performed - no servlets nor weblisteners are detected.
+     * <p></p>
+     * This will most probably cause Vaadin to not work and throw NullPointerException at <code>VaadinServlet.serveStaticOrWebJarRequest</code>.
+     * However, it's a good thing to disable this when starting your app with a QuickStart configuration.
+     */
+    private boolean disableClasspathScanning = false;
+
     /**
      * Creates the new instance of the Boot launcher.
      */
@@ -166,6 +173,18 @@ public String getServerURL() {
         return "http://" + (hostName != null ? hostName : "localhost") + ":" + port + contextRoot;
     }
 
+    /**
+     * If true, no classpath scanning is performed - no servlets nor weblisteners are detected.
+     * <p></p>
+     * This will most probably cause Vaadin to not work and throw NullPointerException at <code>VaadinServlet.serveStaticOrWebJarRequest</code>.
+     * However, it's a good thing to disable this when starting your app with a QuickStart configuration.
+     */
+    @NotNull
+    public VaadinBoot disableClasspathScanning() {
+        disableClasspathScanning = true;
+        return this;
+    }
+
     // mark volatile: might be accessed by the shutdown hook from a different thread.
     private volatile Server server;
 
@@ -264,13 +283,14 @@ protected WebAppContext createWebAppContext() throws IOException {
         context.setBaseResource(Env.findWebRoot());
         context.setContextPath(contextRoot);
         context.addServlet(servlet, "/*");
-        // this will properly scan the classpath for all @WebListeners, including the most important
-        // com.vaadin.flow.server.startup.ServletContextListeners.
-        // See also https://mvysny.github.io/vaadin-lookup-vs-instantiator/
-        // Jetty documentation: https://www.eclipse.org/jetty/documentation/jetty-12/operations-guide/index.html#og-annotations-scanning
-        context.setAttribute("org.eclipse.jetty.server.webapp.ContainerIncludeJarPattern", ".*\\.jar|.*/classes/.*");
-        context.setConfigurationDiscovered(true);
-        context.getServletContext().setExtendedListenerTypes(true);
+        if (!disableClasspathScanning) {
+            // this will properly scan the classpath for all @WebListeners, including the most important
+            // com.vaadin.flow.server.startup.ServletContextListeners.
+            // See also https://mvysny.github.io/vaadin-lookup-vs-instantiator/
+            // Jetty documentation: https://www.eclipse.org/jetty/documentation/jetty-12/operations-guide/index.html#og-annotations-scanning
+            context.setAttribute("org.eclipse.jetty.server.webapp.ContainerIncludeJarPattern", ".*\\.jar|.*/classes/.*");
+            context.setConfigurationDiscovered(true);
+        }
         return context;
     }