Java tutorial
/* * Copyright 2012-2018 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.boot.web.embedded.jetty; import java.net.BindException; import java.util.Arrays; import java.util.List; import java.util.stream.Collectors; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.eclipse.jetty.server.Connector; import org.eclipse.jetty.server.Handler; import org.eclipse.jetty.server.NetworkConnector; import org.eclipse.jetty.server.Server; import org.eclipse.jetty.server.handler.ContextHandler; import org.eclipse.jetty.server.handler.HandlerCollection; import org.eclipse.jetty.server.handler.HandlerWrapper; import org.eclipse.jetty.util.component.AbstractLifeCycle; import org.springframework.boot.web.server.PortInUseException; import org.springframework.boot.web.server.WebServer; import org.springframework.boot.web.server.WebServerException; import org.springframework.util.Assert; import org.springframework.util.ReflectionUtils; import org.springframework.util.StringUtils; /** * {@link WebServer} that can be used to control a Jetty web server. * * @author Phillip Webb * @author Dave Syer * @author David Liu * @author Edd Melndez * @author Brian Clozel * @author Kristine Jetzke * @since 2.0.0 * @see JettyReactiveWebServerFactory */ public class JettyWebServer implements WebServer { private static final Log logger = LogFactory.getLog(JettyWebServer.class); private final Object monitor = new Object(); private final Server server; private final boolean autoStart; private Connector[] connectors; private volatile boolean started; /** * Create a new {@link JettyWebServer} instance. * @param server the underlying Jetty server */ public JettyWebServer(Server server) { this(server, true); } /** * Create a new {@link JettyWebServer} instance. * @param server the underlying Jetty server * @param autoStart if auto-starting the server */ public JettyWebServer(Server server, boolean autoStart) { this.autoStart = autoStart; Assert.notNull(server, "Jetty Server must not be null"); this.server = server; initialize(); } private void initialize() { synchronized (this.monitor) { try { // Cache the connectors and then remove them to prevent requests being // handled before the application context is ready. this.connectors = this.server.getConnectors(); this.server.addBean(new AbstractLifeCycle() { @Override protected void doStart() throws Exception { for (Connector connector : JettyWebServer.this.connectors) { Assert.state(connector.isStopped(), () -> "Connector " + connector + " has been started prematurely"); } JettyWebServer.this.server.setConnectors(null); } }); // Start the server so that the ServletContext is available this.server.start(); this.server.setStopAtShutdown(false); } catch (Throwable ex) { // Ensure process isn't left running stopSilently(); throw new WebServerException("Unable to start embedded Jetty web server", ex); } } } private void stopSilently() { try { this.server.stop(); } catch (Exception ex) { // Ignore } } @Override public void start() throws WebServerException { synchronized (this.monitor) { if (this.started) { return; } this.server.setConnectors(this.connectors); if (!this.autoStart) { return; } try { this.server.start(); for (Handler handler : this.server.getHandlers()) { handleDeferredInitialize(handler); } Connector[] connectors = this.server.getConnectors(); for (Connector connector : connectors) { try { connector.start(); } catch (BindException ex) { if (connector instanceof NetworkConnector) { throw new PortInUseException(((NetworkConnector) connector).getPort()); } throw ex; } } this.started = true; JettyWebServer.logger.info("Jetty started on port(s) " + getActualPortsDescription() + " with context path '" + getContextPath() + "'"); } catch (WebServerException ex) { stopSilently(); throw ex; } catch (Exception ex) { stopSilently(); throw new WebServerException("Unable to start embedded Jetty server", ex); } } } private String getActualPortsDescription() { StringBuilder ports = new StringBuilder(); for (Connector connector : this.server.getConnectors()) { if (ports.length() != 0) { ports.append(", "); } ports.append(getLocalPort(connector)).append(getProtocols(connector)); } return ports.toString(); } private Integer getLocalPort(Connector connector) { try { // Jetty 9 internals are different, but the method name is the same return (Integer) ReflectionUtils .invokeMethod(ReflectionUtils.findMethod(connector.getClass(), "getLocalPort"), connector); } catch (Exception ex) { JettyWebServer.logger.info("could not determine port ( " + ex.getMessage() + ")"); return 0; } } private String getProtocols(Connector connector) { List<String> protocols = connector.getProtocols(); return " (" + StringUtils.collectionToDelimitedString(protocols, ", ") + ")"; } private String getContextPath() { return Arrays.stream(this.server.getHandlers()).filter(ContextHandler.class::isInstance) .map(ContextHandler.class::cast).map(ContextHandler::getContextPath) .collect(Collectors.joining(" ")); } private void handleDeferredInitialize(Handler... handlers) throws Exception { for (Handler handler : handlers) { if (handler instanceof JettyEmbeddedWebAppContext) { ((JettyEmbeddedWebAppContext) handler).deferredInitialize(); } else if (handler instanceof HandlerWrapper) { handleDeferredInitialize(((HandlerWrapper) handler).getHandler()); } else if (handler instanceof HandlerCollection) { handleDeferredInitialize(((HandlerCollection) handler).getHandlers()); } } } @Override public void stop() { synchronized (this.monitor) { this.started = false; try { this.server.stop(); } catch (InterruptedException ex) { Thread.currentThread().interrupt(); } catch (Exception ex) { throw new WebServerException("Unable to stop embedded Jetty server", ex); } } } @Override public int getPort() { Connector[] connectors = this.server.getConnectors(); for (Connector connector : connectors) { // Probably only one... return getLocalPort(connector); } return 0; } /** * Returns access to the underlying Jetty Server. * @return the Jetty server */ public Server getServer() { return this.server; } }