spring TomcatWebServer 源码

springboot TomcatWebServer 代码

文件路径：/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/tomcat/TomcatWebServer.java

/*
 * Copyright 2012-2022 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
 *
 *      https://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.tomcat;

import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.stream.Collectors;

import javax.naming.NamingException;

import org.apache.catalina.Container;
import org.apache.catalina.Context;
import org.apache.catalina.Engine;
import org.apache.catalina.Lifecycle;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.LifecycleState;
import org.apache.catalina.Service;
import org.apache.catalina.connector.Connector;
import org.apache.catalina.startup.Tomcat;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.naming.ContextBindings;

import org.springframework.boot.web.server.GracefulShutdownCallback;
import org.springframework.boot.web.server.GracefulShutdownResult;
import org.springframework.boot.web.server.PortInUseException;
import org.springframework.boot.web.server.Shutdown;
import org.springframework.boot.web.server.WebServer;
import org.springframework.boot.web.server.WebServerException;
import org.springframework.util.Assert;

/**
 * {@link WebServer} that can be used to control a Tomcat web server. Usually this class
 * should be created using the {@link TomcatReactiveWebServerFactory} or
 * {@link TomcatServletWebServerFactory}, but not directly.
 *
 * @author Brian Clozel
 * @author Kristine Jetzke
 * @since 2.0.0
 */
public class TomcatWebServer implements WebServer {

	private static final Log logger = LogFactory.getLog(TomcatWebServer.class);

	private static final AtomicInteger containerCounter = new AtomicInteger(-1);

	private final Object monitor = new Object();

	private final Map<Service, Connector[]> serviceConnectors = new HashMap<>();

	private final Tomcat tomcat;

	private final boolean autoStart;

	private final GracefulShutdown gracefulShutdown;

	private volatile boolean started;

	/**
	 * Create a new {@link TomcatWebServer} instance.
	 * @param tomcat the underlying Tomcat server
	 */
	public TomcatWebServer(Tomcat tomcat) {
		this(tomcat, true);
	}

	/**
	 * Create a new {@link TomcatWebServer} instance.
	 * @param tomcat the underlying Tomcat server
	 * @param autoStart if the server should be started
	 */
	public TomcatWebServer(Tomcat tomcat, boolean autoStart) {
		this(tomcat, autoStart, Shutdown.IMMEDIATE);
	}

	/**
	 * Create a new {@link TomcatWebServer} instance.
	 * @param tomcat the underlying Tomcat server
	 * @param autoStart if the server should be started
	 * @param shutdown type of shutdown supported by the server
	 * @since 2.3.0
	 */
	public TomcatWebServer(Tomcat tomcat, boolean autoStart, Shutdown shutdown) {
		Assert.notNull(tomcat, "Tomcat Server must not be null");
		this.tomcat = tomcat;
		this.autoStart = autoStart;
		this.gracefulShutdown = (shutdown == Shutdown.GRACEFUL) ? new GracefulShutdown(tomcat) : null;
		initialize();
	}

	private void initialize() throws WebServerException {
		logger.info("Tomcat initialized with port(s): " + getPortsDescription(false));
		synchronized (this.monitor) {
			try {
				addInstanceIdToEngineName();

				Context context = findContext();
				context.addLifecycleListener((event) -> {
					if (context.equals(event.getSource()) && Lifecycle.START_EVENT.equals(event.getType())) {
						// Remove service connectors so that protocol binding doesn't
						// happen when the service is started.
						removeServiceConnectors();
					}
				});

				// Start the server to trigger initialization listeners
				this.tomcat.start();

				// We can re-throw failure exception directly in the main thread
				rethrowDeferredStartupExceptions();

				try {
					ContextBindings.bindClassLoader(context, context.getNamingToken(), getClass().getClassLoader());
				}
				catch (NamingException ex) {
					// Naming is not enabled. Continue
				}

				// Unlike Jetty, all Tomcat threads are daemon threads. We create a
				// blocking non-daemon to stop immediate shutdown
				startDaemonAwaitThread();
			}
			catch (Exception ex) {
				stopSilently();
				destroySilently();
				throw new WebServerException("Unable to start embedded Tomcat", ex);
			}
		}
	}

	private Context findContext() {
		for (Container child : this.tomcat.getHost().findChildren()) {
			if (child instanceof Context context) {
				return context;
			}
		}
		throw new IllegalStateException("The host does not contain a Context");
	}

	private void addInstanceIdToEngineName() {
		int instanceId = containerCounter.incrementAndGet();
		if (instanceId > 0) {
			Engine engine = this.tomcat.getEngine();
			engine.setName(engine.getName() + "-" + instanceId);
		}
	}

	private void removeServiceConnectors() {
		for (Service service : this.tomcat.getServer().findServices()) {
			Connector[] connectors = service.findConnectors().clone();
			this.serviceConnectors.put(service, connectors);
			for (Connector connector : connectors) {
				service.removeConnector(connector);
			}
		}
	}

	private void rethrowDeferredStartupExceptions() throws Exception {
		Container[] children = this.tomcat.getHost().findChildren();
		for (Container container : children) {
			if (container instanceof TomcatEmbeddedContext embeddedContext) {
				TomcatStarter tomcatStarter = embeddedContext.getStarter();
				if (tomcatStarter != null) {
					Exception exception = tomcatStarter.getStartUpException();
					if (exception != null) {
						throw exception;
					}
				}
			}
			if (!LifecycleState.STARTED.equals(container.getState())) {
				throw new IllegalStateException(container + " failed to start");
			}
		}
	}

	private void startDaemonAwaitThread() {
		Thread awaitThread = new Thread("container-" + (containerCounter.get())) {

			@Override
			public void run() {
				TomcatWebServer.this.tomcat.getServer().await();
			}

		};
		awaitThread.setContextClassLoader(getClass().getClassLoader());
		awaitThread.setDaemon(false);
		awaitThread.start();
	}

	@Override
	public void start() throws WebServerException {
		synchronized (this.monitor) {
			if (this.started) {
				return;
			}
			try {
				addPreviouslyRemovedConnectors();
				Connector connector = this.tomcat.getConnector();
				if (connector != null && this.autoStart) {
					performDeferredLoadOnStartup();
				}
				checkThatConnectorsHaveStarted();
				this.started = true;
				logger.info("Tomcat started on port(s): " + getPortsDescription(true) + " with context path '"
						+ getContextPath() + "'");
			}
			catch (ConnectorStartFailedException ex) {
				stopSilently();
				throw ex;
			}
			catch (Exception ex) {
				PortInUseException.throwIfPortBindingException(ex, () -> this.tomcat.getConnector().getPort());
				throw new WebServerException("Unable to start embedded Tomcat server", ex);
			}
			finally {
				Context context = findContext();
				ContextBindings.unbindClassLoader(context, context.getNamingToken(), getClass().getClassLoader());
			}
		}
	}

	private void checkThatConnectorsHaveStarted() {
		checkConnectorHasStarted(this.tomcat.getConnector());
		for (Connector connector : this.tomcat.getService().findConnectors()) {
			checkConnectorHasStarted(connector);
		}
	}

	private void checkConnectorHasStarted(Connector connector) {
		if (LifecycleState.FAILED.equals(connector.getState())) {
			throw new ConnectorStartFailedException(connector.getPort());
		}
	}

	private void stopSilently() {
		try {
			stopTomcat();
		}
		catch (LifecycleException ex) {
			// Ignore
		}
	}

	private void destroySilently() {
		try {
			this.tomcat.destroy();
		}
		catch (LifecycleException ex) {
			// Ignore
		}
	}

	private void stopTomcat() throws LifecycleException {
		if (Thread.currentThread().getContextClassLoader() instanceof TomcatEmbeddedWebappClassLoader) {
			Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
		}
		this.tomcat.stop();
	}

	private void addPreviouslyRemovedConnectors() {
		Service[] services = this.tomcat.getServer().findServices();
		for (Service service : services) {
			Connector[] connectors = this.serviceConnectors.get(service);
			if (connectors != null) {
				for (Connector connector : connectors) {
					service.addConnector(connector);
					if (!this.autoStart) {
						stopProtocolHandler(connector);
					}
				}
				this.serviceConnectors.remove(service);
			}
		}
	}

	private void stopProtocolHandler(Connector connector) {
		try {
			connector.getProtocolHandler().stop();
		}
		catch (Exception ex) {
			logger.error("Cannot pause connector: ", ex);
		}
	}

	private void performDeferredLoadOnStartup() {
		try {
			for (Container child : this.tomcat.getHost().findChildren()) {
				if (child instanceof TomcatEmbeddedContext embeddedContext) {
					embeddedContext.deferredLoadOnStartup();
				}
			}
		}
		catch (Exception ex) {
			if (ex instanceof WebServerException webServerException) {
				throw webServerException;
			}
			throw new WebServerException("Unable to start embedded Tomcat connectors", ex);
		}
	}

	Map<Service, Connector[]> getServiceConnectors() {
		return this.serviceConnectors;
	}

	@Override
	public void stop() throws WebServerException {
		synchronized (this.monitor) {
			boolean wasStarted = this.started;
			try {
				this.started = false;
				try {
					if (this.gracefulShutdown != null) {
						this.gracefulShutdown.abort();
					}
					stopTomcat();
					this.tomcat.destroy();
				}
				catch (LifecycleException ex) {
					// swallow and continue
				}
			}
			catch (Exception ex) {
				throw new WebServerException("Unable to stop embedded Tomcat", ex);
			}
			finally {
				if (wasStarted) {
					containerCounter.decrementAndGet();
				}
			}
		}
	}

	private String getPortsDescription(boolean localPort) {
		StringBuilder ports = new StringBuilder();
		for (Connector connector : this.tomcat.getService().findConnectors()) {
			if (ports.length() != 0) {
				ports.append(' ');
			}
			int port = localPort ? connector.getLocalPort() : connector.getPort();
			ports.append(port).append(" (").append(connector.getScheme()).append(')');
		}
		return ports.toString();
	}

	@Override
	public int getPort() {
		Connector connector = this.tomcat.getConnector();
		if (connector != null) {
			return connector.getLocalPort();
		}
		return -1;
	}

	private String getContextPath() {
		return Arrays.stream(this.tomcat.getHost().findChildren()).filter(TomcatEmbeddedContext.class::isInstance)
				.map(TomcatEmbeddedContext.class::cast).map(TomcatEmbeddedContext::getPath)
				.collect(Collectors.joining(" "));
	}

	/**
	 * Returns access to the underlying Tomcat server.
	 * @return the Tomcat server
	 */
	public Tomcat getTomcat() {
		return this.tomcat;
	}

	@Override
	public void shutDownGracefully(GracefulShutdownCallback callback) {
		if (this.gracefulShutdown == null) {
			callback.shutdownComplete(GracefulShutdownResult.IMMEDIATE);
			return;
		}
		this.gracefulShutdown.shutDownGracefully(callback);
	}

}

相关信息

spring 源码目录

相关文章

spring CompressionConnectorCustomizer 源码

spring ConfigurableTomcatWebServerFactory 源码

spring ConnectorStartFailedException 源码

spring ConnectorStartFailureAnalyzer 源码

spring DisableReferenceClearingContextCustomizer 源码

spring GracefulShutdown 源码

spring LazySessionIdGenerator 源码

spring SslConnectorCustomizer 源码

spring TldPatterns 源码

spring TomcatConnectorCustomizer 源码